From c3c9cf3380b36634ca02767a1fb903416012bdce Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Mon, 2 Jan 2023 15:21:57 -0500
Subject: [PATCH 01/36] feat: incomplete parser

---
 lib/formdata/constants.js |  30 ++++++
 lib/formdata/parser.js    | 218 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 248 insertions(+)
 create mode 100644 lib/formdata/constants.js
 create mode 100644 lib/formdata/parser.js

diff --git a/lib/formdata/constants.js b/lib/formdata/constants.js
new file mode 100644
index 00000000000..fed0a6071e1
--- /dev/null
+++ b/lib/formdata/constants.js
@@ -0,0 +1,30 @@
+'use strict'
+
+const states = {
+  INITIAL: 0,
+  BOUNDARY: 1,
+  READ_HEADERS: 2,
+  READ_BODY: 3
+}
+
+const headerStates = {
+  DEFAULT: -1, // no match
+  FIRST: 0,
+  SECOND: 1,
+  THIRD: 2
+}
+
+const chars = {
+  '-': '-'.charCodeAt(0),
+  cr: '\r'.charCodeAt(0),
+  lf: '\n'.charCodeAt(0)
+}
+
+const dashes = Buffer.from('--')
+
+module.exports = {
+  states,
+  chars,
+  headerStates,
+  dashes
+}
diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
new file mode 100644
index 00000000000..e91d8a337df
--- /dev/null
+++ b/lib/formdata/parser.js
@@ -0,0 +1,218 @@
+'use strict'
+
+const { Writable } = require('stream')
+const { states, chars, headerStates, dashes } = require('./constants')
+const { parseMIMEType } = require('../fetch/dataURL')
+
+class FormDataParser extends Writable {
+  /** @type {Buffer[]} */
+  #buffers = []
+  #byteOffset = 0
+
+  #state = states.INITIAL
+
+  /** @type {Buffer} */
+  #boundary
+
+  #info = {
+    headerState: headerStates.DEFAULT,
+    rawHeaders: null,
+    bodyState: {
+      buffersChecked: 0,
+      byteOffset: 0
+    },
+    bodyChunks: []
+  }
+
+  constructor (opts) {
+    super(opts)
+
+    const contentType = opts.headers.get?.('content-type') ?? opts.headers['content-type']
+    const mimeType = contentType ? parseMIMEType(contentType) : null
+
+    if (mimeType === null || mimeType.essence !== 'multipart/form-data') {
+      this.destroy(new Error('Invalid mimetype essence.'))
+      return
+    } else if (!mimeType.parameters.has('boundary')) {
+      this.destroy(new Error('No boundary parameter.'))
+    }
+
+    this.#boundary = Buffer.from(mimeType.parameters.get('boundary'))
+  }
+
+  /**
+   * @param {Buffer} chunk
+   * @param {() => void} callback
+   */
+  _write (chunk, _, callback) {
+    this.#buffers.push(chunk)
+    this.#byteOffset += chunk.length
+
+    this.run(callback)
+  }
+
+  /**
+   * @param {() => void} callback
+   */
+  run (callback) {
+    while (true) {
+      if (this.#state === states.INITIAL) {
+        if (this.#byteOffset < 2) {
+          return callback()
+        }
+
+        const bytes = this.consume(2)
+
+        if (bytes[0] !== chars['-'] || bytes[1] !== chars['-']) {
+          this.destroy(new Error('FormData should start with --'))
+          return
+        }
+
+        this.#state = states.BOUNDARY
+      } else if (this.#state === states.BOUNDARY) {
+        if (this.#byteOffset < this.#boundary.length + 2) {
+          return callback()
+        }
+
+        const bytes = this.consume(this.#boundary.length)
+        const nextBytes = this.consume(2) // \r\n OR --
+
+        if (bytes.toString() !== this.#boundary) {
+          this.destroy(new Error('Received invalid boundary'))
+          return
+        } else if (nextBytes?.[0] !== chars.cr || nextBytes?.[1] !== chars.lf) {
+          if (nextBytes?.[0] === chars['-'] && nextBytes?.[1] === chars['-']) {
+            // Done parsing form-data
+            // TODO: emit event or something
+            this.end()
+            return
+          }
+
+          this.destroy(new Error('Boundary did not end with CRLF'))
+          return
+        }
+
+        this.#state = states.READ_HEADERS
+      } else if (this.#state === states.READ_HEADERS) {
+        // There can be an arbitrary amount of headers and each one has an
+        // arbitrary length. Therefore it's easier to read the headers, and
+        // then parse once we receive 2 CRLFs which marks the body's start.
+
+        if (this.#byteOffset === 0) {
+          return callback()
+        }
+
+        let buffersToRemove = 0
+        // number of bytes to remove from the last buffer
+        let bytesToRemove = 0
+
+        done: {
+          for (let i = 0; i < this.#buffers.length; i++) {
+            const buffer = this.#buffers[i]
+
+            for (let j = 0; j < buffer.length; j++) {
+              const byte = buffer[j]
+              const state = this.#info.headerState
+
+              if (byte === chars.cr && state === headerStates.DEFAULT) {
+                this.#info.headerState = headerStates.FIRST
+              } else if (byte === chars.lf && state === headerStates.FIRST) {
+                this.#info.headerState = headerStates.SECOND
+              } else if (byte === chars.cr && state === headerStates.SECOND) {
+                this.#info.headerState = headerStates.THIRD
+              } else if (byte === chars.lf && state === headerStates.THIRD) {
+                // Got \r\n\r\n which marks the end of the headers.
+                this.#state = states.READ_BODY
+                
+                break done
+              } else {
+                bytesToRemove += 1
+                this.#info.headerState = headerStates.DEFAULT
+              }
+            }
+
+            bytesToRemove = 0
+            buffersToRemove += 1
+          }
+        }
+
+        const headers = []
+        let headersLength = 0
+
+        while (buffersToRemove-- > 0) {
+          const buffer = this.#buffers.shift()
+          headers.push(buffer)
+          headersLength += buffer.length
+        }
+
+        if (bytesToRemove > 0) {
+          const header = this.#buffers[0].subarray(0, bytesToRemove)
+          headers.push(header)
+          headersLength += header.length
+
+          this.#buffers[0] = this.#buffers[0].subarray(bytesToRemove)
+        }
+
+        this.#byteOffset -= headersLength
+        this.consume(4) // remove \r\n\r\n
+        this.#info.rawHeaders = Buffer.concat(headers, headersLength)
+      } else if (this.#state === states.READ_BODY) {
+        // A part's body can contain CRLFs so they cannot be used to
+        // determine when the body ends. We need to check if a chunk
+        // (or chunks) contains the boundary to stop parsing the body.
+
+        if (this.#byteOffset < this.#boundary.length) {
+          return callback()
+        }
+
+        
+      }
+    }
+  }
+
+  /**
+   * Take n bytes from the buffered Buffers
+   * @param {number} n
+   * @returns {Buffer|null}
+   */
+  consume (n) {
+    if (n > this.#byteOffset) {
+      return null
+    } else if (n === 0) {
+      return emptyBuffer
+    }
+
+    if (this.#buffers[0].length === n) {
+      this.#byteOffset -= this.#buffers[0].length
+      return this.#buffers.shift()
+    }
+
+    const buffer = Buffer.allocUnsafe(n)
+    let offset = 0
+
+    while (offset !== n) {
+      const next = this.#buffers[0]
+      const { length } = next
+
+      if (length + offset === n) {
+        buffer.set(this.#buffers.shift(), offset)
+        break
+      } else if (length + offset > n) {
+        buffer.set(next.subarray(0, n - offset), offset)
+        this.#buffers[0] = next.subarray(n - offset)
+        break
+      } else {
+        buffer.set(this.#buffers.shift(), offset)
+        offset += next.length
+      }
+    }
+
+    this.#byteOffset -= n
+
+    return buffer
+  }
+}
+
+module.exports = {
+  FormDataParser
+}

From 438b7a3a61b19ec055ed6234a308acd236053efb Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Wed, 4 Jan 2023 12:06:15 -0500
Subject: [PATCH 02/36] feat: add in basic body parsing algorithm

---
 lib/formdata/constants.js |  4 +-
 lib/formdata/parser.js    | 85 +++++++++++++++++++++++++++++----------
 2 files changed, 65 insertions(+), 24 deletions(-)

diff --git a/lib/formdata/constants.js b/lib/formdata/constants.js
index fed0a6071e1..3e701791e03 100644
--- a/lib/formdata/constants.js
+++ b/lib/formdata/constants.js
@@ -20,11 +20,11 @@ const chars = {
   lf: '\n'.charCodeAt(0)
 }
 
-const dashes = Buffer.from('--')
+const emptyBuffer = Buffer.alloc(0)
 
 module.exports = {
   states,
   chars,
   headerStates,
-  dashes
+  emptyBuffer
 }
diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index e91d8a337df..d45bef12cf5 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -1,7 +1,7 @@
 'use strict'
 
 const { Writable } = require('stream')
-const { states, chars, headerStates, dashes } = require('./constants')
+const { states, chars, headerStates, emptyBuffer } = require('./constants')
 const { parseMIMEType } = require('../fetch/dataURL')
 
 class FormDataParser extends Writable {
@@ -17,11 +17,7 @@ class FormDataParser extends Writable {
   #info = {
     headerState: headerStates.DEFAULT,
     rawHeaders: null,
-    bodyState: {
-      buffersChecked: 0,
-      byteOffset: 0
-    },
-    bodyChunks: []
+    body: null
   }
 
   constructor (opts) {
@@ -77,11 +73,11 @@ class FormDataParser extends Writable {
         const bytes = this.consume(this.#boundary.length)
         const nextBytes = this.consume(2) // \r\n OR --
 
-        if (bytes.toString() !== this.#boundary) {
+        if (!this.#boundary.equals(bytes)) {
           this.destroy(new Error('Received invalid boundary'))
           return
-        } else if (nextBytes?.[0] !== chars.cr || nextBytes?.[1] !== chars.lf) {
-          if (nextBytes?.[0] === chars['-'] && nextBytes?.[1] === chars['-']) {
+        } else if (nextBytes[0] !== chars.cr || nextBytes[1] !== chars.lf) {
+          if (nextBytes[0] === chars['-'] && nextBytes[1] === chars['-']) {
             // Done parsing form-data
             // TODO: emit event or something
             this.end()
@@ -106,15 +102,23 @@ class FormDataParser extends Writable {
         // number of bytes to remove from the last buffer
         let bytesToRemove = 0
 
-        done: {
-          for (let i = 0; i < this.#buffers.length; i++) {
-            const buffer = this.#buffers[i]
-
-            for (let j = 0; j < buffer.length; j++) {
-              const byte = buffer[j]
+        done: { // eslint-disable-line no-labels
+          for (const buffer of this.#buffers) {
+            for (const byte of buffer) {
               const state = this.#info.headerState
 
-              if (byte === chars.cr && state === headerStates.DEFAULT) {
+              if (byte !== chars.cr && byte !== chars.lf) {
+                // Some pieces may have multiple headers, separated by \r\n.
+                // We need to also consider those bytes.
+                if (state === headerStates.FIRST) { // \r
+                  bytesToRemove += 1
+                } else if (state === headerStates.SECOND) { // \r\n
+                  bytesToRemove += 2
+                }
+
+                bytesToRemove += 1
+                this.#info.headerState = headerStates.DEFAULT
+              } else if (byte === chars.cr && state === headerStates.DEFAULT) {
                 this.#info.headerState = headerStates.FIRST
               } else if (byte === chars.lf && state === headerStates.FIRST) {
                 this.#info.headerState = headerStates.SECOND
@@ -123,11 +127,8 @@ class FormDataParser extends Writable {
               } else if (byte === chars.lf && state === headerStates.THIRD) {
                 // Got \r\n\r\n which marks the end of the headers.
                 this.#state = states.READ_BODY
-                
-                break done
-              } else {
-                bytesToRemove += 1
-                this.#info.headerState = headerStates.DEFAULT
+
+                break done // eslint-disable-line no-labels
               }
             }
 
@@ -165,7 +166,47 @@ class FormDataParser extends Writable {
           return callback()
         }
 
-        
+        /** @type {Buffer} */
+        let buffer = this.#buffers.shift()
+        let bufferLength = buffer.length
+
+        while (!buffer.includes(this.#boundary)) {
+          // No more buffers to check
+          if (this.#byteOffset === 0) {
+            this.#buffers.unshift(buffer)
+            buffer = undefined
+            return callback()
+          }
+
+          const next = this.#buffers.shift()
+          this.#byteOffset -= next.length
+          bufferLength += next.length
+          buffer = Buffer.concat([buffer, next], bufferLength)
+        }
+
+        if (bufferLength === this.#boundary.length) {
+          this.#buffers.unshift(buffer)
+          this.#byteOffset += buffer.length
+
+          this.#state = states.BOUNDARY
+        } else {
+          const idx = buffer.indexOf(this.#boundary)
+          const rest = buffer.subarray(idx)
+
+          this.#info.body = buffer.subarray(0, idx - 4) // remove \r\n--
+
+          // TODO: emit event here
+          // TODO: parse headers here
+          console.log({
+            raw: this.#info.rawHeaders.toString(),
+            body: this.#info.body.toString()
+          })
+
+          this.#buffers.unshift(rest)
+          this.#byteOffset += rest.length
+
+          this.#state = states.BOUNDARY
+        }
       }
     }
   }

From 3c6f6f86219befa7235cc45810528e19dbbb2954 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Wed, 4 Jan 2023 12:55:11 -0500
Subject: [PATCH 03/36] fix: remove unused body var

---
 lib/formdata/filestream.js | 11 +++++++++++
 lib/formdata/parser.js     | 24 ++++++++++++++++++------
 2 files changed, 29 insertions(+), 6 deletions(-)
 create mode 100644 lib/formdata/filestream.js

diff --git a/lib/formdata/filestream.js b/lib/formdata/filestream.js
new file mode 100644
index 00000000000..a6eb360c69a
--- /dev/null
+++ b/lib/formdata/filestream.js
@@ -0,0 +1,11 @@
+'use strict'
+
+const { Readable } = require('stream')
+
+class FileStream extends Readable {
+  _read () {}
+}
+
+module.exports = {
+  FileStream
+}
diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index d45bef12cf5..870387e1a97 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -2,6 +2,7 @@
 
 const { Writable } = require('stream')
 const { states, chars, headerStates, emptyBuffer } = require('./constants')
+const { FileStream } = require('./filestream')
 const { parseMIMEType } = require('../fetch/dataURL')
 
 class FormDataParser extends Writable {
@@ -17,7 +18,7 @@ class FormDataParser extends Writable {
   #info = {
     headerState: headerStates.DEFAULT,
     rawHeaders: null,
-    body: null
+    stream: null
   }
 
   constructor (opts) {
@@ -166,6 +167,8 @@ class FormDataParser extends Writable {
           return callback()
         }
 
+        this.#info.stream ??= new FileStream()
+
         /** @type {Buffer} */
         let buffer = this.#buffers.shift()
         let bufferLength = buffer.length
@@ -178,6 +181,17 @@ class FormDataParser extends Writable {
             return callback()
           }
 
+          const doubleDashIdx = buffer.length ? buffer.indexOf('--') : null
+
+          if (doubleDashIdx === -1) {
+            // Chunk is completely useless, emit it
+            this.#info.stream.push(buffer)
+            buffer = emptyBuffer
+          } else if (doubleDashIdx + this.#boundary.length >= buffer.length) {
+            this.#info.stream.push(buffer)
+            buffer = emptyBuffer
+          }
+
           const next = this.#buffers.shift()
           this.#byteOffset -= next.length
           bufferLength += next.length
@@ -193,14 +207,12 @@ class FormDataParser extends Writable {
           const idx = buffer.indexOf(this.#boundary)
           const rest = buffer.subarray(idx)
 
-          this.#info.body = buffer.subarray(0, idx - 4) // remove \r\n--
+          this.#info.stream.push(buffer.subarray(0, idx - 4)) // remove \r\n--
+          // TODO: clean up stream
+          // this.#info.stream.push(null)
 
           // TODO: emit event here
           // TODO: parse headers here
-          console.log({
-            raw: this.#info.rawHeaders.toString(),
-            body: this.#info.body.toString()
-          })
 
           this.#buffers.unshift(rest)
           this.#byteOffset += rest.length

From 4866b9a9592c5848df4325d9fbe6c8ca752dcde7 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Wed, 4 Jan 2023 12:59:10 -0500
Subject: [PATCH 04/36] fix: cleanup

---
 lib/formdata/parser.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 870387e1a97..dcb98a0dece 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -187,9 +187,13 @@ class FormDataParser extends Writable {
             // Chunk is completely useless, emit it
             this.#info.stream.push(buffer)
             buffer = emptyBuffer
-          } else if (doubleDashIdx + this.#boundary.length >= buffer.length) {
+            bufferLength = 0
+          } else if (doubleDashIdx + this.#boundary.length < buffer.length) {
+            // If the double dash index is not part of the boundary and
+            // not a chunked piece of the boundary
             this.#info.stream.push(buffer)
             buffer = emptyBuffer
+            bufferLength = 0
           }
 
           const next = this.#buffers.shift()

From acb3fef0c1ed4120533c334149dab9731b222569 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Fri, 6 Jan 2023 18:30:46 -0500
Subject: [PATCH 05/36] feat: parse headers and emit file event

---
 lib/fetch/dataURL.js      |  18 ++++-
 lib/formdata/constants.js |   7 +-
 lib/formdata/parser.js    | 148 +++++++++++++++++++++++++++++++++++---
 3 files changed, 158 insertions(+), 15 deletions(-)

diff --git a/lib/fetch/dataURL.js b/lib/fetch/dataURL.js
index beefad15482..d287c5ad27e 100644
--- a/lib/fetch/dataURL.js
+++ b/lib/fetch/dataURL.js
@@ -132,11 +132,16 @@ function URLSerializer (url, excludeFragment = false) {
 
 // https://infra.spec.whatwg.org/#collect-a-sequence-of-code-points
 /**
- * @param {(char: string) => boolean} condition
- * @param {string} input
+ * @template {string|Buffer} T
+ * @param {(char: T[number]) => boolean} condition
+ * @param {T} input
  * @param {{ position: number }} position
+ * @returns {T}
  */
 function collectASequenceOfCodePoints (condition, input, position) {
+  const inputIsString = typeof input === 'string'
+  const start = position.position
+
   // 1. Let result be the empty string.
   let result = ''
 
@@ -144,13 +149,20 @@ function collectASequenceOfCodePoints (condition, input, position) {
   // code point at position within input meets the condition condition:
   while (position.position < input.length && condition(input[position.position])) {
     // 1. Append that code point to the end of result.
-    result += input[position.position]
+    if (inputIsString) {
+      result += input[position.position]
+    }
 
     // 2. Advance position by 1.
     position.position++
   }
 
   // 3. Return result.
+
+  if (!inputIsString) {
+    return input.subarray(start, position.position)
+  }
+
   return result
 }
 
diff --git a/lib/formdata/constants.js b/lib/formdata/constants.js
index 3e701791e03..1bac7259edb 100644
--- a/lib/formdata/constants.js
+++ b/lib/formdata/constants.js
@@ -17,7 +17,12 @@ const headerStates = {
 const chars = {
   '-': '-'.charCodeAt(0),
   cr: '\r'.charCodeAt(0),
-  lf: '\n'.charCodeAt(0)
+  lf: '\n'.charCodeAt(0),
+  ':': ':'.charCodeAt(0),
+  ' ': ' '.charCodeAt(0), // 0x20
+  ';': ';'.charCodeAt(0),
+  '=': '='.charCodeAt(0),
+  '"': '"'.charCodeAt(0)
 }
 
 const emptyBuffer = Buffer.alloc(0)
diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index dcb98a0dece..0cfa60e3fc3 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -3,7 +3,11 @@
 const { Writable } = require('stream')
 const { states, chars, headerStates, emptyBuffer } = require('./constants')
 const { FileStream } = require('./filestream')
-const { parseMIMEType } = require('../fetch/dataURL')
+const {
+  parseMIMEType,
+  collectASequenceOfCodePoints,
+  collectAnHTTPQuotedString
+} = require('../fetch/dataURL')
 
 class FormDataParser extends Writable {
   /** @type {Buffer[]} */
@@ -18,7 +22,9 @@ class FormDataParser extends Writable {
   #info = {
     headerState: headerStates.DEFAULT,
     rawHeaders: null,
-    stream: null
+    stream: null,
+    headers: null,
+    fileName: ''
   }
 
   constructor (opts) {
@@ -136,9 +142,11 @@ class FormDataParser extends Writable {
             bytesToRemove = 0
             buffersToRemove += 1
           }
+
+          return callback()
         }
 
-        const headers = []
+        const headers = this.#info.rawHeaders ?? []
         let headersLength = 0
 
         while (buffersToRemove-- > 0) {
@@ -157,7 +165,15 @@ class FormDataParser extends Writable {
 
         this.#byteOffset -= headersLength
         this.consume(4) // remove \r\n\r\n
-        this.#info.rawHeaders = Buffer.concat(headers, headersLength)
+        this.#parseRawHeaders(Buffer.concat(headers, headersLength))
+
+        this.#info.stream = new FileStream()
+        this.emit(
+          'file',
+          this.#info.fileName,
+          this.#info.stream,
+          {} // TODO
+        )
       } else if (this.#state === states.READ_BODY) {
         // A part's body can contain CRLFs so they cannot be used to
         // determine when the body ends. We need to check if a chunk
@@ -167,8 +183,6 @@ class FormDataParser extends Writable {
           return callback()
         }
 
-        this.#info.stream ??= new FileStream()
-
         /** @type {Buffer} */
         let buffer = this.#buffers.shift()
         let bufferLength = buffer.length
@@ -212,11 +226,7 @@ class FormDataParser extends Writable {
           const rest = buffer.subarray(idx)
 
           this.#info.stream.push(buffer.subarray(0, idx - 4)) // remove \r\n--
-          // TODO: clean up stream
-          // this.#info.stream.push(null)
-
-          // TODO: emit event here
-          // TODO: parse headers here
+          this.#info.stream.destroy()
 
           this.#buffers.unshift(rest)
           this.#byteOffset += rest.length
@@ -268,6 +278,122 @@ class FormDataParser extends Writable {
 
     return buffer
   }
+
+  /**
+   * @param {Buffer} buffer
+   */
+  #parseRawHeaders (buffer) {
+    this.#info.rawHeaders = null
+
+    // https://www.rfc-editor.org/rfc/rfc7578#section-4.8
+
+    const headers = {}
+    const position = { position: 0 }
+
+    while (position.position < buffer.length) {
+      const nameBuffer = collectASequenceOfCodePoints(
+        (char) => char !== chars[':'],
+        buffer,
+        position
+      )
+
+      // Invalid header; has no value
+      if (position.position >= buffer.length) {
+        break
+      }
+
+      // MIME header fields in multipart bodies are required to
+      // consist only of 7-bit data in the US-ASCII character set
+      const name = nameBuffer.toString('ascii').toLowerCase()
+
+      if (
+        name !== 'content-type' &&
+        name !== 'content-disposition' &&
+        name !== 'content-transfer-encoding'
+      ) {
+        // The multipart/form-data media type does not support any MIME header
+        // fields in parts other than Content-Type, Content-Disposition, and (in
+        // limited circumstances) Content-Transfer-Encoding.  Other header
+        // fields MUST NOT be included and MUST be ignored.
+
+        // Go to the next header if one is available. Headers are split by \r\n,
+        // so we skip all characters until the sequence is found.
+        collectASequenceOfCodePoints(
+          (char) => char !== chars.cr && buffer[position.position + 1] !== chars.lf,
+          buffer,
+          position
+        )
+
+        continue
+      }
+
+      if (buffer[position.position + 1] === chars[' ']) {
+        position.position += 2 // skip "; "
+      } else {
+        position.position++ // skip ":"
+      }
+
+      const value = collectASequenceOfCodePoints(
+        (char) => {
+          if (name === 'content-disposition') {
+            // mimetypes (ie. from a content-type header) can have
+            // a semicolon in it. In that case, we want to read the
+            // entire value in, not just until we reach a semicolon
+            return char !== chars[';']
+          }
+
+          return char !== chars.cr && buffer[position.position + 1] !== chars.lf
+        },
+        buffer,
+        position
+      )
+
+      headers[name] = value.toString('ascii')
+
+      // No attributes
+      if (position.position >= buffer.length) {
+        continue
+      }
+
+      const attributes = collectASequenceOfCodePoints(
+        (char) => char !== chars.cr && buffer[position.position + 1] !== chars.lf,
+        buffer,
+        position
+      )
+
+      if (name === 'content-disposition') {
+        const attrs = attributes.toString('ascii').slice(1)
+
+        const equalIdx = attrs.indexOf('=')
+        const attrName = attrs.slice(0, equalIdx).trim()
+        const attrValue = attrs.slice(equalIdx + 1)
+
+        const position = { position: 0 }
+        const value = attrValue[0] === '"'
+          ? collectAnHTTPQuotedString(attrValue, position, true)
+          : attrValue
+
+        // TODO: match busboy's behavior with error handling
+        if (attrName !== 'name') {
+          this.destroy('Invalid attribute')
+          return
+        }
+
+        this.#info.fileName = value
+      }
+
+      position.position += 2 // skip \r\n
+    }
+
+    // Validate the header values here
+    // TODO: match busboy's behavior with error handling
+    if (headers['content-disposition'] !== 'form-data') {
+      this.destroy(new Error('received invalid content-disposition header'))
+      return
+    }
+
+    this.#info.headers = headers
+  }
 }
 
 module.exports = {

From 2d4decdc437e4c2572fadd3e6380c5ee56bad639 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Fri, 6 Jan 2023 23:43:42 -0500
Subject: [PATCH 06/36] fix: differentiate between file and field and parse
 header attributes correctly

---
 lib/formdata/parser.js | 145 +++++++++++++++++++++++++++++++----------
 1 file changed, 110 insertions(+), 35 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 0cfa60e3fc3..1136cf35a19 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -23,8 +23,10 @@ class FormDataParser extends Writable {
     headerState: headerStates.DEFAULT,
     rawHeaders: null,
     stream: null,
-    headers: null,
-    fileName: ''
+    body: {
+      chunks: [],
+      length: 0
+    }
   }
 
   constructor (opts) {
@@ -165,15 +167,30 @@ class FormDataParser extends Writable {
 
         this.#byteOffset -= headersLength
         this.consume(4) // remove \r\n\r\n
-        this.#parseRawHeaders(Buffer.concat(headers, headersLength))
-
-        this.#info.stream = new FileStream()
-        this.emit(
-          'file',
-          this.#info.fileName,
-          this.#info.stream,
-          {} // TODO
+        const { headers: receivedHeaders, attributes } = this.#parseRawHeaders(
+          Buffer.concat(headers, headersLength)
         )
+
+        if (
+          attributes.filename !== undefined ||
+          receivedHeaders['content-type'] === 'application/octet-stream'
+        ) {
+          this.#info.stream = new FileStream()
+
+          this.emit(
+            'file',
+            attributes.name, // name is a required attribute
+            this.#info.stream,
+            {
+              filename: attributes.filename ?? '',
+              encoding: receivedHeaders['content-transfer-encoding'] ?? '7bit',
+              mimeType: receivedHeaders['content-type'] ?? 'application/octet-stream'
+            }
+          )
+        } else {
+          this.#info.headers = receivedHeaders
+          this.#info.attributes = attributes
+        }
       } else if (this.#state === states.READ_BODY) {
         // A part's body can contain CRLFs so they cannot be used to
         // determine when the body ends. We need to check if a chunk
@@ -199,13 +216,25 @@ class FormDataParser extends Writable {
 
           if (doubleDashIdx === -1) {
             // Chunk is completely useless, emit it
-            this.#info.stream.push(buffer)
+            if (this.#info.stream !== null) {
+              this.#info.stream.push(buffer)
+            } else {
+              this.#info.body.chunks.push(buffer)
+              this.#info.body.length += buffer.length
+            }
+
             buffer = emptyBuffer
             bufferLength = 0
           } else if (doubleDashIdx + this.#boundary.length < buffer.length) {
             // If the double dash index is not part of the boundary and
             // not a chunked piece of the boundary
-            this.#info.stream.push(buffer)
+            if (this.#info.stream !== null) {
+              this.#info.stream.push(buffer)
+            } else {
+              this.#info.body.chunks.push(buffer)
+              this.#info.body.length += buffer.length
+            }
+
             buffer = emptyBuffer
             bufferLength = 0
           }
@@ -225,8 +254,36 @@ class FormDataParser extends Writable {
           const idx = buffer.indexOf(this.#boundary)
           const rest = buffer.subarray(idx)
 
-          this.#info.stream.push(buffer.subarray(0, idx - 4)) // remove \r\n--
-          this.#info.stream.destroy()
+          const chunk = buffer.subarray(0, idx - 4) // remove \r\n--
+
+          if (this.#info.stream !== null) {
+            this.#info.stream.push(chunk)
+            this.#info.stream.destroy()
+          } else {
+            const { headers, attributes, body } = this.#info
+
+            body.chunks.push(chunk)
+            body.length += chunk.length
+
+            const fullBody = new TextDecoder('utf-8', { fatal: true }).decode(
+              Buffer.concat(body.chunks, body.length)
+            )
+
+            this.emit(
+              'field',
+              attributes.name,
+              fullBody,
+              {
+                nameTruncated: false, // todo
+                valueTruncated: false, // todo
+                encoding: headers['content-transfer-encoding'] ?? '7bit',
+                mimeType: headers['content-type'] ?? 'text/plain'
+              }
+            )
+
+            body.chunks.length = 0
+            body.length = 0
+          }
 
           this.#buffers.unshift(rest)
           this.#byteOffset += rest.length
@@ -288,6 +345,8 @@ class FormDataParser extends Writable {
     // https://www.rfc-editor.org/rfc/rfc7578#section-4.8
 
     const headers = {}
+    const attributes = {}
+
     const position = { position: 0 }
 
     while (position.position < buffer.length) {
@@ -355,31 +414,44 @@ class FormDataParser extends Writable {
         continue
       }
 
-      const attributes = collectASequenceOfCodePoints(
-        (char) => char !== chars.cr && buffer[position.position + 1] !== chars.lf,
-        buffer,
-        position
-      )
+      if (name !== 'content-disposition') {
+        collectASequenceOfCodePoints(
+          (char) => char !== chars.cr && buffer[position.position + 1] !== chars.lf,
+          buffer,
+          position
+        )
+      } else {
+        // A content-disposition header can contain multiple attributes,
+        // separated with a semicolon in the form of name=value.
 
-      if (name === 'content-disposition') {
-        const attrs = attributes.toString('ascii').slice(1)
+        while (position.position < buffer.length) {
+          position.position++ // skip ";"
 
-        const equalIdx = attrs.indexOf('=')
-        const attrName = attrs.slice(0, equalIdx).trim()
-        const attrValue = attrs.slice(equalIdx + 1)
+          const collected = collectASequenceOfCodePoints(
+            (char) => {
+              if (char === chars.cr) {
+                return buffer[position.position + 1] !== chars.lf
+              }
 
-        const position = { position: 0 }
-        const value = attrValue[0] === '"'
-          ? collectAnHTTPQuotedString(attrValue, position, true)
-          : attrValue
+              return char !== chars[';']
+            },
+            buffer,
+            position
+          )
 
-        // TODO: match busboy's behavior with error handling
-        if (attrName !== 'name') {
-          this.destroy('Invalid attribute')
-          return
-        }
+          const attribute = collected.toString('ascii')
+          const equalIdx = attribute.indexOf('=')
+          const name = attribute.slice(0, equalIdx).trim()
+          const value = attribute[equalIdx + 1] === '"'
+            ? collectAnHTTPQuotedString(attribute.slice(equalIdx + 1), { position: 0 }, true)
+            : attribute.slice(equalIdx + 1)
+
+          attributes[name] = value
 
-        this.#info.fileName = value
+          if (buffer[position.position] === chars.cr) {
+            break
+          }
+        }
       }
 
       position.position += 2 // skip \r\n
@@ -390,9 +462,12 @@ class FormDataParser extends Writable {
     if (headers['content-disposition'] !== 'form-data') {
       this.destroy(new Error('received invalid content-disposition header'))
       return
+    } else if (attributes.name === undefined) {
+      this.destroy(new Error('Content-Disposition had no name attribute'))
+      return
     }
 
-    this.#info.headers = headers
+    return { headers, attributes }
   }
 }
 

From ae7c177bf901142100c1e755dc205a3bbd4f2e54 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sat, 7 Jan 2023 10:52:50 -0500
Subject: [PATCH 07/36] run busboy test & support charset options

---
 index.js                                     |   4 +
 lib/formdata/parser.js                       |  23 ++--
 test/busboy/LICENSE                          |  19 ++++
 test/busboy/common.js                        | 105 +++++++++++++++++++
 test/busboy/test-types-multipart-charsets.js |  97 +++++++++++++++++
 5 files changed, 240 insertions(+), 8 deletions(-)
 create mode 100644 test/busboy/LICENSE
 create mode 100644 test/busboy/common.js
 create mode 100644 test/busboy/test-types-multipart-charsets.js

diff --git a/index.js b/index.js
index 02ac246fa45..713fa4aa394 100644
--- a/index.js
+++ b/index.js
@@ -141,6 +141,10 @@ if (util.nodeMajor >= 18 && hasCrypto) {
   const { WebSocket } = require('./lib/websocket/websocket')
 
   module.exports.WebSocket = WebSocket
+
+  const { FormDataParser } = require('./lib/formdata/parser')
+
+  module.exports.FormDataParser = FormDataParser
 }
 
 module.exports.request = makeDispatcher(api.request)
diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 1136cf35a19..0b316a19ccc 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -29,6 +29,8 @@ class FormDataParser extends Writable {
     }
   }
 
+  #opts = {}
+
   constructor (opts) {
     super(opts)
 
@@ -43,6 +45,11 @@ class FormDataParser extends Writable {
     }
 
     this.#boundary = Buffer.from(mimeType.parameters.get('boundary'))
+
+    if (opts) {
+      this.#opts.defCharset = opts.defCharset ?? 'utf8'
+      this.#opts.defParamCharset = opts.defParamCharset ?? 'utf8'
+    }
   }
 
   /**
@@ -88,8 +95,8 @@ class FormDataParser extends Writable {
         } else if (nextBytes[0] !== chars.cr || nextBytes[1] !== chars.lf) {
           if (nextBytes[0] === chars['-'] && nextBytes[1] === chars['-']) {
             // Done parsing form-data
-            // TODO: emit event or something
-            this.end()
+
+            this.destroy()
             return
           }
 
@@ -158,11 +165,10 @@ class FormDataParser extends Writable {
         }
 
         if (bytesToRemove > 0) {
-          const header = this.#buffers[0].subarray(0, bytesToRemove)
-          headers.push(header)
-          headersLength += header.length
+          const removed = this.consume(bytesToRemove)
 
-          this.#buffers[0] = this.#buffers[0].subarray(bytesToRemove)
+          headers.push(removed)
+          headersLength += removed.length
         }
 
         this.#byteOffset -= headersLength
@@ -176,6 +182,7 @@ class FormDataParser extends Writable {
           receivedHeaders['content-type'] === 'application/octet-stream'
         ) {
           this.#info.stream = new FileStream()
+          this.#info.stream.truncated = false // TODO
 
           this.emit(
             'file',
@@ -363,7 +370,7 @@ class FormDataParser extends Writable {
 
       // MIME header fields in multipart bodies are required to
       // consist only of 7-bit data in the US-ASCII character set
-      const name = nameBuffer.toString('ascii').toLowerCase()
+      const name = nameBuffer.toString(this.#opts.defCharset).toLowerCase()
 
       if (
         name !== 'content-type' &&
@@ -439,7 +446,7 @@ class FormDataParser extends Writable {
             position
           )
 
-          const attribute = collected.toString('ascii')
+          const attribute = collected.toString(this.#opts.defParamCharset)
           const equalIdx = attribute.indexOf('=')
           const name = attribute.slice(0, equalIdx).trim()
           const value = attribute[equalIdx + 1] === '"'
diff --git a/test/busboy/LICENSE b/test/busboy/LICENSE
new file mode 100644
index 00000000000..290762e94f4
--- /dev/null
+++ b/test/busboy/LICENSE
@@ -0,0 +1,19 @@
+Copyright Brian White. All rights reserved.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to
+deal in the Software without restriction, including without limitation the
+rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+IN THE SOFTWARE.
\ No newline at end of file
diff --git a/test/busboy/common.js b/test/busboy/common.js
new file mode 100644
index 00000000000..c2ed9c47c03
--- /dev/null
+++ b/test/busboy/common.js
@@ -0,0 +1,105 @@
+'use strict'
+
+const assert = require('assert')
+const { inspect } = require('util')
+
+const mustCallChecks = []
+
+function noop () {}
+
+function runCallChecks (exitCode) {
+  if (exitCode !== 0) return
+
+  const failed = mustCallChecks.filter((context) => {
+    if ('minimum' in context) {
+      context.messageSegment = `at least ${context.minimum}`
+      return context.actual < context.minimum
+    }
+    context.messageSegment = `exactly ${context.exact}`
+    return context.actual !== context.exact
+  })
+
+  failed.forEach((context) => {
+    console.error('Mismatched %s function calls. Expected %s, actual %d.',
+      context.name,
+      context.messageSegment,
+      context.actual)
+    console.error(context.stack.split('\n').slice(2).join('\n'))
+  })
+
+  if (failed.length) { process.exit(1) }
+}
+
+function mustCall (fn, exact) {
+  return _mustCallInner(fn, exact, 'exact')
+}
+
+function mustCallAtLeast (fn, minimum) {
+  return _mustCallInner(fn, minimum, 'minimum')
+}
+
+function _mustCallInner (fn, criteria = 1, field) {
+  if (process._exiting) { throw new Error('Cannot use common.mustCall*() in process exit handler') }
+
+  if (typeof fn === 'number') {
+    criteria = fn
+    fn = noop
+  } else if (fn === undefined) {
+    fn = noop
+  }
+
+  if (typeof criteria !== 'number') { throw new TypeError(`Invalid ${field} value: ${criteria}`) }
+
+  const context = {
+    [field]: criteria,
+    actual: 0,
+    stack: inspect(new Error()),
+    name: fn.name || '<anonymous>'
+  }
+
+  // Add the exit listener only once to avoid listener leak warnings
+  if (mustCallChecks.length === 0) { process.on('exit', runCallChecks) }
+
+  mustCallChecks.push(context)
+
+  function wrapped (...args) {
+    ++context.actual
+    return fn.call(this, ...args)
+  }
+  // TODO: remove origFn?
+  wrapped.origFn = fn
+
+  return wrapped
+}
+
+function getCallSite (top) {
+  const originalStackFormatter = Error.prepareStackTrace
+  Error.prepareStackTrace = (_err, stack) =>
+    `${stack[0].getFileName()}:${stack[0].getLineNumber()}`
+  const err = new Error()
+  Error.captureStackTrace(err, top)
+  // With the V8 Error API, the stack is not formatted until it is accessed
+  // eslint-disable-next-line no-unused-expressions
+  err.stack
+  Error.prepareStackTrace = originalStackFormatter
+  return err.stack
+}
+
+function mustNotCall (msg) {
+  const callSite = getCallSite(mustNotCall)
+  return function mustNotCall (...args) {
+    args = args.map(inspect).join(', ')
+    const argsInfo = (args.length > 0
+      ? `\ncalled with arguments: ${args}`
+      : '')
+    assert.fail(
+      `${msg || 'function should not have been called'} at ${callSite}` +
+        argsInfo)
+  }
+}
+
+module.exports = {
+  mustCall,
+  mustCallAtLeast,
+  mustNotCall
+}
diff --git a/test/busboy/test-types-multipart-charsets.js b/test/busboy/test-types-multipart-charsets.js
new file mode 100644
index 00000000000..d143a7654ac
--- /dev/null
+++ b/test/busboy/test-types-multipart-charsets.js
@@ -0,0 +1,97 @@
+'use strict'
+
+const assert = require('assert')
+const { inspect } = require('util')
+const { join } = require('path')
+
+const { mustCall } = require(join(__dirname, 'common.js'))
+
+const { FormDataParser } = require('../..')
+const busboy = (opts) => new FormDataParser(opts)
+
+const input = Buffer.from([
+  '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+  'Content-Disposition: form-data; ' +
+   'name="upload_file_0"; filename="テスト.dat"',
+  'Content-Type: application/octet-stream',
+  '',
+  'A'.repeat(1023),
+  '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+].join('\r\n'))
+const boundary = '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k'
+const expected = [
+  {
+    type: 'file',
+    name: 'upload_file_0',
+    data: Buffer.from('A'.repeat(1023)),
+    info: {
+      filename: 'テスト.dat',
+      encoding: '7bit',
+      mimeType: 'application/octet-stream'
+    },
+    limited: false
+  }
+]
+const bb = busboy({
+  defParamCharset: 'utf8',
+  headers: {
+    'content-type': `multipart/form-data; boundary=${boundary}`
+  }
+})
+const results = []
+
+bb.on('field', (name, val, info) => {
+  results.push({ type: 'field', name, val, info })
+})
+
+bb.on('file', (name, stream, info) => {
+  const data = []
+  let nb = 0
+  const file = {
+    type: 'file',
+    name,
+    data: null,
+    info,
+    limited: false
+  }
+  results.push(file)
+  stream.on('data', (d) => {
+    data.push(d)
+    nb += d.length
+  }).on('limit', () => {
+    file.limited = true
+  }).on('close', () => {
+    file.data = Buffer.concat(data, nb)
+    assert.strictEqual(stream.truncated, file.limited)
+  }).once('error', (err) => {
+    file.err = err.message
+  })
+})
+
+bb.on('error', (err) => {
+  results.push({ error: err.message })
+})
+
+bb.on('partsLimit', () => {
+  results.push('partsLimit')
+})
+
+bb.on('filesLimit', () => {
+  results.push('filesLimit')
+})
+
+bb.on('fieldsLimit', () => {
+  results.push('fieldsLimit')
+})
+
+bb.on('close', mustCall(() => {
+  assert.deepStrictEqual(
+    results,
+    expected,
+    'Results mismatch.\n' +
+      `Parsed: ${inspect(results)}\n` +
+      `Expected: ${inspect(expected)}`
+  )
+}))
+
+bb.end(input)

From 1d665b9cbd649fe716db849a923179eaaaa18e85 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sat, 7 Jan 2023 12:51:23 -0500
Subject: [PATCH 08/36] fix: byte-by-byte receiving

---
 lib/formdata/parser.js | 17 +++--------------
 1 file changed, 3 insertions(+), 14 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 0b316a19ccc..f4886939fe1 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -110,11 +110,10 @@ class FormDataParser extends Writable {
         // arbitrary length. Therefore it's easier to read the headers, and
         // then parse once we receive 2 CRLFs which marks the body's start.
 
-        if (this.#byteOffset === 0) {
+        if (this.#byteOffset < 4) {
           return callback()
         }
 
-        let buffersToRemove = 0
         // number of bytes to remove from the last buffer
         let bytesToRemove = 0
 
@@ -147,9 +146,6 @@ class FormDataParser extends Writable {
                 break done // eslint-disable-line no-labels
               }
             }
-
-            bytesToRemove = 0
-            buffersToRemove += 1
           }
 
           return callback()
@@ -158,12 +154,6 @@ class FormDataParser extends Writable {
         const headers = this.#info.rawHeaders ?? []
         let headersLength = 0
 
-        while (buffersToRemove-- > 0) {
-          const buffer = this.#buffers.shift()
-          headers.push(buffer)
-          headersLength += buffer.length
-        }
-
         if (bytesToRemove > 0) {
           const removed = this.consume(bytesToRemove)
 
@@ -171,7 +161,6 @@ class FormDataParser extends Writable {
           headersLength += removed.length
         }
 
-        this.#byteOffset -= headersLength
         this.consume(4) // remove \r\n\r\n
         const { headers: receivedHeaders, attributes } = this.#parseRawHeaders(
           Buffer.concat(headers, headersLength)
@@ -208,13 +197,14 @@ class FormDataParser extends Writable {
         }
 
         /** @type {Buffer} */
-        let buffer = this.#buffers.shift()
+        let buffer = this.consume(this.#byteOffset)
         let bufferLength = buffer.length
 
         while (!buffer.includes(this.#boundary)) {
           // No more buffers to check
           if (this.#byteOffset === 0) {
             this.#buffers.unshift(buffer)
+            this.#byteOffset += buffer.length
             buffer = undefined
             return callback()
           }
@@ -260,7 +250,6 @@ class FormDataParser extends Writable {
         } else {
           const idx = buffer.indexOf(this.#boundary)
           const rest = buffer.subarray(idx)
-
           const chunk = buffer.subarray(0, idx - 4) // remove \r\n--
 
           if (this.#info.stream !== null) {

From 6ec1fd318f35c45c4b21e6714dc60b738990888b Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sat, 7 Jan 2023 12:51:36 -0500
Subject: [PATCH 09/36] fix: byte-by-byte receiving

---
 test/busboy/test-types-multipart.js | 1113 +++++++++++++++++++++++++++
 1 file changed, 1113 insertions(+)
 create mode 100644 test/busboy/test-types-multipart.js

diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
new file mode 100644
index 00000000000..d0d76c0a6e1
--- /dev/null
+++ b/test/busboy/test-types-multipart.js
@@ -0,0 +1,1113 @@
+'use strict'
+
+const assert = require('assert')
+const { inspect } = require('util')
+
+const { FormDataParser } = require('../..')
+const busboy = (opts) => new FormDataParser(opts)
+
+const active = new Map()
+
+const tests = [
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; name="file_name_0"',
+        '',
+        'super alpha file',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; name="file_name_1"',
+        '',
+        'super beta file',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_0"; filename="1k_a.dat"',
+        'Content-Type: application/octet-stream',
+        '',
+        'A'.repeat(1023),
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_1"; filename="1k_b.dat"',
+        'Content-Type: application/octet-stream',
+        '',
+        'B'.repeat(1023),
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    expected: [
+      {
+        type: 'field',
+        name: 'file_name_0',
+        val: 'super alpha file',
+        info: {
+          nameTruncated: false,
+          valueTruncated: false,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        }
+      },
+      {
+        type: 'field',
+        name: 'file_name_1',
+        val: 'super beta file',
+        info: {
+          nameTruncated: false,
+          valueTruncated: false,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        }
+      },
+      {
+        type: 'file',
+        name: 'upload_file_0',
+        data: Buffer.from('A'.repeat(1023)),
+        info: {
+          filename: '1k_a.dat',
+          encoding: '7bit',
+          mimeType: 'application/octet-stream'
+        },
+        limited: false
+      },
+      {
+        type: 'file',
+        name: 'upload_file_1',
+        data: Buffer.from('B'.repeat(1023)),
+        info: {
+          filename: '1k_b.dat',
+          encoding: '7bit',
+          mimeType: 'application/octet-stream'
+        },
+        limited: false
+      }
+    ],
+    what: 'Fields and files'
+  },
+  {
+    source: [
+      ['------WebKitFormBoundaryTB2MiQ36fnSJlrhY',
+        'Content-Disposition: form-data; name="cont"',
+        '',
+        'some random content',
+        '------WebKitFormBoundaryTB2MiQ36fnSJlrhY',
+        'Content-Disposition: form-data; name="pass"',
+        '',
+        'some random pass',
+        '------WebKitFormBoundaryTB2MiQ36fnSJlrhY',
+        'Content-Disposition: form-data; name=bit',
+        '',
+        '2',
+        '------WebKitFormBoundaryTB2MiQ36fnSJlrhY--'
+      ].join('\r\n')
+    ],
+    boundary: '----WebKitFormBoundaryTB2MiQ36fnSJlrhY',
+    expected: [
+      {
+        type: 'field',
+        name: 'cont',
+        val: 'some random content',
+        info: {
+          nameTruncated: false,
+          valueTruncated: false,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        }
+      },
+      {
+        type: 'field',
+        name: 'pass',
+        val: 'some random pass',
+        info: {
+          nameTruncated: false,
+          valueTruncated: false,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        }
+      },
+      {
+        type: 'field',
+        name: 'bit',
+        val: '2',
+        info: {
+          nameTruncated: false,
+          valueTruncated: false,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        }
+      }
+    ],
+    what: 'Fields only'
+  },
+  {
+    source: [
+      ''
+    ],
+    boundary: '----WebKitFormBoundaryTB2MiQ36fnSJlrhY',
+    expected: [
+      { error: 'Unexpected end of form' }
+    ],
+    what: 'No fields and no files'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; name="file_name_0"',
+        '',
+        'super alpha file',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_0"; filename="1k_a.dat"',
+        'Content-Type: application/octet-stream',
+        '',
+        'ABCDEFGHIJKLMNOPQRSTUVWXYZ',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    limits: {
+      fileSize: 13,
+      fieldSize: 5
+    },
+    expected: [
+      {
+        type: 'field',
+        name: 'file_name_0',
+        val: 'super',
+        info: {
+          nameTruncated: false,
+          valueTruncated: true,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        }
+      },
+      {
+        type: 'file',
+        name: 'upload_file_0',
+        data: Buffer.from('ABCDEFGHIJKLM'),
+        info: {
+          filename: '1k_a.dat',
+          encoding: '7bit',
+          mimeType: 'application/octet-stream'
+        },
+        limited: true
+      }
+    ],
+    what: 'Fields and files (limits)'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; name="file_name_0"',
+        '',
+        'super alpha file',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_0"; filename="1k_a.dat"',
+        'Content-Type: application/octet-stream',
+        '',
+        'ABCDEFGHIJKLMNOPQRSTUVWXYZ',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    limits: {
+      files: 0
+    },
+    expected: [
+      {
+        type: 'field',
+        name: 'file_name_0',
+        val: 'super alpha file',
+        info: {
+          nameTruncated: false,
+          valueTruncated: false,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        }
+      },
+      'filesLimit'
+    ],
+    what: 'Fields and files (limits: 0 files)'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; name="file_name_0"',
+        '',
+        'super alpha file',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; name="file_name_1"',
+        '',
+        'super beta file',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_0"; filename="1k_a.dat"',
+        'Content-Type: application/octet-stream',
+        '',
+        'A'.repeat(1023),
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_1"; filename="1k_b.dat"',
+        'Content-Type: application/octet-stream',
+        '',
+        'B'.repeat(1023),
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    expected: [
+      {
+        type: 'field',
+        name: 'file_name_0',
+        val: 'super alpha file',
+        info: {
+          nameTruncated: false,
+          valueTruncated: false,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        }
+      },
+      {
+        type: 'field',
+        name: 'file_name_1',
+        val: 'super beta file',
+        info: {
+          nameTruncated: false,
+          valueTruncated: false,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        }
+      }
+    ],
+    events: ['field'],
+    what: 'Fields and (ignored) files'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_0"; filename="/tmp/1k_a.dat"',
+        'Content-Type: application/octet-stream',
+        '',
+        'ABCDEFGHIJKLMNOPQRSTUVWXYZ',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_1"; filename="C:\\files\\1k_b.dat"',
+        'Content-Type: application/octet-stream',
+        '',
+        'ABCDEFGHIJKLMNOPQRSTUVWXYZ',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_2"; filename="relative/1k_c.dat"',
+        'Content-Type: application/octet-stream',
+        '',
+        'ABCDEFGHIJKLMNOPQRSTUVWXYZ',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    expected: [
+      {
+        type: 'file',
+        name: 'upload_file_0',
+        data: Buffer.from('ABCDEFGHIJKLMNOPQRSTUVWXYZ'),
+        info: {
+          filename: '1k_a.dat',
+          encoding: '7bit',
+          mimeType: 'application/octet-stream'
+        },
+        limited: false
+      },
+      {
+        type: 'file',
+        name: 'upload_file_1',
+        data: Buffer.from('ABCDEFGHIJKLMNOPQRSTUVWXYZ'),
+        info: {
+          filename: '1k_b.dat',
+          encoding: '7bit',
+          mimeType: 'application/octet-stream'
+        },
+        limited: false
+      },
+      {
+        type: 'file',
+        name: 'upload_file_2',
+        data: Buffer.from('ABCDEFGHIJKLMNOPQRSTUVWXYZ'),
+        info: {
+          filename: '1k_c.dat',
+          encoding: '7bit',
+          mimeType: 'application/octet-stream'
+        },
+        limited: false
+      }
+    ],
+    what: 'Files with filenames containing paths'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_0"; filename="/absolute/1k_a.dat"',
+        'Content-Type: application/octet-stream',
+        '',
+        'ABCDEFGHIJKLMNOPQRSTUVWXYZ',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_1"; filename="C:\\absolute\\1k_b.dat"',
+        'Content-Type: application/octet-stream',
+        '',
+        'ABCDEFGHIJKLMNOPQRSTUVWXYZ',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_2"; filename="relative/1k_c.dat"',
+        'Content-Type: application/octet-stream',
+        '',
+        'ABCDEFGHIJKLMNOPQRSTUVWXYZ',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    preservePath: true,
+    expected: [
+      {
+        type: 'file',
+        name: 'upload_file_0',
+        data: Buffer.from('ABCDEFGHIJKLMNOPQRSTUVWXYZ'),
+        info: {
+          filename: '/absolute/1k_a.dat',
+          encoding: '7bit',
+          mimeType: 'application/octet-stream'
+        },
+        limited: false
+      },
+      {
+        type: 'file',
+        name: 'upload_file_1',
+        data: Buffer.from('ABCDEFGHIJKLMNOPQRSTUVWXYZ'),
+        info: {
+          filename: 'C:\\absolute\\1k_b.dat',
+          encoding: '7bit',
+          mimeType: 'application/octet-stream'
+        },
+        limited: false
+      },
+      {
+        type: 'file',
+        name: 'upload_file_2',
+        data: Buffer.from('ABCDEFGHIJKLMNOPQRSTUVWXYZ'),
+        info: {
+          filename: 'relative/1k_c.dat',
+          encoding: '7bit',
+          mimeType: 'application/octet-stream'
+        },
+        limited: false
+      }
+    ],
+    what: 'Paths to be preserved through the preservePath option'
+  },
+  {
+    source: [
+      ['------WebKitFormBoundaryTB2MiQ36fnSJlrhY',
+        'Content-Disposition: form-data; name="cont"',
+        'Content-Type: ',
+        '',
+        'some random content',
+        '------WebKitFormBoundaryTB2MiQ36fnSJlrhY',
+        'Content-Disposition: ',
+        '',
+        'some random pass',
+        '------WebKitFormBoundaryTB2MiQ36fnSJlrhY--'
+      ].join('\r\n')
+    ],
+    boundary: '----WebKitFormBoundaryTB2MiQ36fnSJlrhY',
+    expected: [
+      {
+        type: 'field',
+        name: 'cont',
+        val: 'some random content',
+        info: {
+          nameTruncated: false,
+          valueTruncated: false,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        }
+      }
+    ],
+    what: 'Empty content-type and empty content-disposition'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="file"; filename*=utf-8\'\'n%C3%A4me.txt',
+        'Content-Type: application/octet-stream',
+        '',
+        'ABCDEFGHIJKLMNOPQRSTUVWXYZ',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    expected: [
+      {
+        type: 'file',
+        name: 'file',
+        data: Buffer.from('ABCDEFGHIJKLMNOPQRSTUVWXYZ'),
+        info: {
+          filename: 'näme.txt',
+          encoding: '7bit',
+          mimeType: 'application/octet-stream'
+        },
+        limited: false
+      }
+    ],
+    what: 'Unicode filenames'
+  },
+  {
+    source: [
+      ['--asdasdasdasd\r\n',
+        'Content-Type: text/plain\r\n',
+        'Content-Disposition: form-data; name="foo"\r\n',
+        '\r\n',
+        'asd\r\n',
+        '--asdasdasdasd--'
+      ].join(':)')
+    ],
+    boundary: 'asdasdasdasd',
+    expected: [
+      { error: 'Malformed part header' },
+      { error: 'Unexpected end of form' }
+    ],
+    what: 'Stopped mid-header'
+  },
+  {
+    source: [
+      ['------WebKitFormBoundaryTB2MiQ36fnSJlrhY',
+        'Content-Disposition: form-data; name="cont"',
+        'Content-Type: application/json',
+        '',
+        '{}',
+        '------WebKitFormBoundaryTB2MiQ36fnSJlrhY--'
+      ].join('\r\n')
+    ],
+    boundary: '----WebKitFormBoundaryTB2MiQ36fnSJlrhY',
+    expected: [
+      {
+        type: 'field',
+        name: 'cont',
+        val: '{}',
+        info: {
+          nameTruncated: false,
+          valueTruncated: false,
+          encoding: '7bit',
+          mimeType: 'application/json'
+        }
+      }
+    ],
+    what: 'content-type for fields'
+  },
+  {
+    source: [
+      '------WebKitFormBoundaryTB2MiQ36fnSJlrhY--'
+    ],
+    boundary: '----WebKitFormBoundaryTB2MiQ36fnSJlrhY',
+    expected: [],
+    what: 'empty form'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name=upload_file_0; filename="1k_a.dat"',
+        'Content-Type: application/octet-stream',
+        'Content-Transfer-Encoding: binary',
+        '',
+        ''
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    expected: [
+      {
+        type: 'file',
+        name: 'upload_file_0',
+        data: Buffer.alloc(0),
+        info: {
+          filename: '1k_a.dat',
+          encoding: 'binary',
+          mimeType: 'application/octet-stream'
+        },
+        limited: false,
+        err: 'Unexpected end of form'
+      },
+      { error: 'Unexpected end of form' }
+    ],
+    what: 'Stopped mid-file #1'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name=upload_file_0; filename="1k_a.dat"',
+        'Content-Type: application/octet-stream',
+        '',
+        'a'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    expected: [
+      {
+        type: 'file',
+        name: 'upload_file_0',
+        data: Buffer.from('a'),
+        info: {
+          filename: '1k_a.dat',
+          encoding: '7bit',
+          mimeType: 'application/octet-stream'
+        },
+        limited: false,
+        err: 'Unexpected end of form'
+      },
+      { error: 'Unexpected end of form' }
+    ],
+    what: 'Stopped mid-file #2'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_0"; filename="notes.txt"',
+        'Content-Type: text/plain; charset=utf8',
+        '',
+        'a',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    expected: [
+      {
+        type: 'file',
+        name: 'upload_file_0',
+        data: Buffer.from('a'),
+        info: {
+          filename: 'notes.txt',
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        },
+        limited: false
+      }
+    ],
+    what: 'Text file with charset'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_0"; filename="notes.txt"',
+        'Content-Type: ',
+        ' text/plain; charset=utf8',
+        '',
+        'a',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    expected: [
+      {
+        type: 'file',
+        name: 'upload_file_0',
+        data: Buffer.from('a'),
+        info: {
+          filename: 'notes.txt',
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        },
+        limited: false
+      }
+    ],
+    what: 'Folded header value'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Type: text/plain; charset=utf8',
+        '',
+        'a',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    expected: [],
+    what: 'No Content-Disposition'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; name="file_name_0"',
+        '',
+        'a'.repeat(64 * 1024),
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_0"; filename="notes.txt"',
+        'Content-Type: ',
+        ' text/plain; charset=utf8',
+        '',
+        'bc',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    limits: {
+      fieldSize: Infinity
+    },
+    expected: [
+      {
+        type: 'file',
+        name: 'upload_file_0',
+        data: Buffer.from('bc'),
+        info: {
+          filename: 'notes.txt',
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        },
+        limited: false
+      }
+    ],
+    events: ['file'],
+    what: 'Skip field parts if no listener'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; name="file_name_0"',
+        '',
+        'a',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_0"; filename="notes.txt"',
+        'Content-Type: ',
+        ' text/plain; charset=utf8',
+        '',
+        'bc',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    limits: {
+      parts: 1
+    },
+    expected: [
+      {
+        type: 'field',
+        name: 'file_name_0',
+        val: 'a',
+        info: {
+          nameTruncated: false,
+          valueTruncated: false,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        }
+      },
+      'partsLimit'
+    ],
+    what: 'Parts limit'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; name="file_name_0"',
+        '',
+        'a',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; name="file_name_1"',
+        '',
+        'b',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    limits: {
+      fields: 1
+    },
+    expected: [
+      {
+        type: 'field',
+        name: 'file_name_0',
+        val: 'a',
+        info: {
+          nameTruncated: false,
+          valueTruncated: false,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        }
+      },
+      'fieldsLimit'
+    ],
+    what: 'Fields limit'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_0"; filename="notes.txt"',
+        'Content-Type: text/plain; charset=utf8',
+        '',
+        'ab',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_1"; filename="notes2.txt"',
+        'Content-Type: text/plain; charset=utf8',
+        '',
+        'cd',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    limits: {
+      files: 1
+    },
+    expected: [
+      {
+        type: 'file',
+        name: 'upload_file_0',
+        data: Buffer.from('ab'),
+        info: {
+          filename: 'notes.txt',
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        },
+        limited: false
+      },
+      'filesLimit'
+    ],
+    what: 'Files limit'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         `name="upload_file_0"; filename="${'a'.repeat(64 * 1024)}.txt"`,
+        'Content-Type: text/plain; charset=utf8',
+        '',
+        'ab',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_1"; filename="notes2.txt"',
+        'Content-Type: text/plain; charset=utf8',
+        '',
+        'cd',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    expected: [
+      { error: 'Malformed part header' },
+      {
+        type: 'file',
+        name: 'upload_file_1',
+        data: Buffer.from('cd'),
+        info: {
+          filename: 'notes2.txt',
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        },
+        limited: false
+      }
+    ],
+    what: 'Oversized part header'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         'name="upload_file_0"; filename="notes.txt"',
+        'Content-Type: text/plain; charset=utf8',
+        '',
+        'a'.repeat(31) + '\r'
+      ].join('\r\n'),
+      'b'.repeat(40),
+      '\r\n-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    fileHwm: 32,
+    expected: [
+      {
+        type: 'file',
+        name: 'upload_file_0',
+        data: Buffer.from('a'.repeat(31) + '\r' + 'b'.repeat(40)),
+        info: {
+          filename: 'notes.txt',
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        },
+        limited: false
+      }
+    ],
+    what: 'Lookbehind data should not stall file streams'
+  },
+  {
+    source: [
+      ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         `name="upload_file_0"; filename="${'a'.repeat(8 * 1024)}.txt"`,
+        'Content-Type: text/plain; charset=utf8',
+        '',
+        'ab',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         `name="upload_file_1"; filename="${'b'.repeat(8 * 1024)}.txt"`,
+        'Content-Type: text/plain; charset=utf8',
+        '',
+        'cd',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+        'Content-Disposition: form-data; ' +
+         `name="upload_file_2"; filename="${'c'.repeat(8 * 1024)}.txt"`,
+        'Content-Type: text/plain; charset=utf8',
+        '',
+        'ef',
+        '-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k--'
+      ].join('\r\n')
+    ],
+    boundary: '---------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
+    expected: [
+      {
+        type: 'file',
+        name: 'upload_file_0',
+        data: Buffer.from('ab'),
+        info: {
+          filename: `${'a'.repeat(8 * 1024)}.txt`,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        },
+        limited: false
+      },
+      {
+        type: 'file',
+        name: 'upload_file_1',
+        data: Buffer.from('cd'),
+        info: {
+          filename: `${'b'.repeat(8 * 1024)}.txt`,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        },
+        limited: false
+      },
+      {
+        type: 'file',
+        name: 'upload_file_2',
+        data: Buffer.from('ef'),
+        info: {
+          filename: `${'c'.repeat(8 * 1024)}.txt`,
+          encoding: '7bit',
+          mimeType: 'text/plain'
+        },
+        limited: false
+      }
+    ],
+    what: 'Header size limit should be per part'
+  },
+  {
+    source: [
+      '\r\n--d1bf46b3-aa33-4061-b28d-6c5ced8b08ee\r\n',
+      'Content-Type: application/gzip\r\n' +
+        'Content-Encoding: gzip\r\n' +
+        'Content-Disposition: form-data; name=batch-1; filename=batch-1' +
+        '\r\n\r\n',
+      '\r\n--d1bf46b3-aa33-4061-b28d-6c5ced8b08ee--'
+    ],
+    boundary: 'd1bf46b3-aa33-4061-b28d-6c5ced8b08ee',
+    expected: [
+      {
+        type: 'file',
+        name: 'batch-1',
+        data: Buffer.alloc(0),
+        info: {
+          filename: 'batch-1',
+          encoding: '7bit',
+          mimeType: 'application/gzip'
+        },
+        limited: false
+      }
+    ],
+    what: 'Empty part'
+  }
+]
+
+for (const test of tests.slice(0, 1)) {
+  active.set(test, 1)
+
+  const { what, boundary, events, limits, preservePath, fileHwm } = test
+  const bb = busboy({
+    fileHwm,
+    limits,
+    preservePath,
+    headers: {
+      'content-type': `multipart/form-data; boundary=${boundary}`
+    }
+  })
+  const results = []
+
+  if (events === undefined || events.includes('field')) {
+    bb.on('field', (name, val, info) => {
+      results.push({ type: 'field', name, val, info })
+    })
+  }
+
+  if (events === undefined || events.includes('file')) {
+    bb.on('file', (name, stream, info) => {
+      const data = []
+      let nb = 0
+      const file = {
+        type: 'file',
+        name,
+        data: null,
+        info,
+        limited: false
+      }
+      results.push(file)
+      stream.on('data', (d) => {
+        data.push(d)
+        nb += d.length
+      }).on('limit', () => {
+        file.limited = true
+      }).on('close', () => {
+        file.data = Buffer.concat(data, nb)
+        assert.strictEqual(stream.truncated, file.limited)
+      }).once('error', (err) => {
+        file.err = err.message
+      })
+    })
+  }
+
+  bb.on('error', (err) => {
+    results.push({ error: err.message })
+  })
+
+  bb.on('partsLimit', () => {
+    results.push('partsLimit')
+  })
+
+  bb.on('filesLimit', () => {
+    results.push('filesLimit')
+  })
+
+  bb.on('fieldsLimit', () => {
+    results.push('fieldsLimit')
+  })
+
+  bb.on('close', () => {
+    active.delete(test)
+
+    assert.deepStrictEqual(
+      results,
+      test.expected,
+      `[${what}] Results mismatch.\n` +
+        `Parsed: ${inspect(results)}\n` +
+        `Expected: ${inspect(test.expected)}`
+    )
+  })
+
+  for (const src of test.source) {
+    const buf = (typeof src === 'string' ? Buffer.from(src, 'utf8') : src)
+    bb.write(buf)
+  }
+  bb.end()
+}
+
+// Byte-by-byte versions
+for (let test of tests.slice(0, 1)) {
+  test = { ...test }
+  test.what += ' (byte-by-byte)'
+  active.set(test, 1)
+
+  const { what, boundary, events, limits, preservePath, fileHwm } = test
+  const bb = busboy({
+    fileHwm,
+    limits,
+    preservePath,
+    headers: {
+      'content-type': `multipart/form-data; boundary=${boundary}`
+    }
+  })
+  const results = []
+
+  if (events === undefined || events.includes('field')) {
+    bb.on('field', (name, val, info) => {
+      results.push({ type: 'field', name, val, info })
+    })
+  }
+
+  if (events === undefined || events.includes('file')) {
+    bb.on('file', (name, stream, info) => {
+      const data = []
+      let nb = 0
+      const file = {
+        type: 'file',
+        name,
+        data: null,
+        info,
+        limited: false
+      }
+      results.push(file)
+      stream.on('data', (d) => {
+        data.push(d)
+        nb += d.length
+      }).on('limit', () => {
+        file.limited = true
+      }).on('close', () => {
+        file.data = Buffer.concat(data, nb)
+        assert.strictEqual(stream.truncated, file.limited)
+      }).once('error', (err) => {
+        file.err = err.message
+      })
+    })
+  }
+
+  bb.on('error', (err) => {
+    results.push({ error: err.message })
+  })
+
+  bb.on('partsLimit', () => {
+    results.push('partsLimit')
+  })
+
+  bb.on('filesLimit', () => {
+    results.push('filesLimit')
+  })
+
+  bb.on('fieldsLimit', () => {
+    results.push('fieldsLimit')
+  })
+
+  bb.on('close', () => {
+    active.delete(test)
+
+    assert.deepStrictEqual(
+      results,
+      test.expected,
+      `[${what}] Results mismatch.\n` +
+        `Parsed: ${inspect(results)}\n` +
+        `Expected: ${inspect(test.expected)}`
+    )
+  })
+
+  for (const src of test.source) {
+    const buf = (typeof src === 'string' ? Buffer.from(src, 'utf8') : src)
+    for (let i = 0; i < buf.length; ++i) { bb.write(buf.slice(i, i + 1)) }
+  }
+  bb.end()
+}
+
+{
+  let exception = false
+  process.once('uncaughtException', (ex) => {
+    exception = true
+    throw ex
+  })
+  process.on('exit', () => {
+    if (exception || active.size === 0) { return }
+    process.exitCode = 1
+    console.error('==========================')
+    console.error(`${active.size} test(s) did not finish:`)
+    console.error('==========================')
+    console.error(Array.from(active.keys()).map((v) => v.what).join('\n'))
+  })
+}

From 119e172d36e599a1747ee861b8179af5d2160ff5 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sat, 7 Jan 2023 13:03:27 -0500
Subject: [PATCH 10/36] fix: error on _final if parsing isn't complete

---
 lib/formdata/parser.js              | 13 ++++++++++++-
 test/busboy/test-types-multipart.js |  4 ++--
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index f4886939fe1..4266c4a77a8 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -26,7 +26,8 @@ class FormDataParser extends Writable {
     body: {
       chunks: [],
       length: 0
-    }
+    },
+    complete: false
   }
 
   #opts = {}
@@ -63,6 +64,15 @@ class FormDataParser extends Writable {
     this.run(callback)
   }
 
+  /**
+   * @param {(error?: Error | null) => void)} cb
+   */
+  _final (cb) {
+    if (!this.#info.complete) {
+      return cb(new Error('Unexpected end of form'))
+    }
+  }
+
   /**
    * @param {() => void} callback
    */
@@ -96,6 +106,7 @@ class FormDataParser extends Writable {
           if (nextBytes[0] === chars['-'] && nextBytes[1] === chars['-']) {
             // Done parsing form-data
 
+            this.#info.complete = true
             this.destroy()
             return
           }
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index d0d76c0a6e1..4e48e8e029a 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -931,7 +931,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 1)) {
+for (const test of tests.slice(0, 3)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1013,7 @@ for (const test of tests.slice(0, 1)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 1)) {
+for (let test of tests.slice(0, 3)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From b902ef10ac8082c7dab0d4db24b72ce1cb212099 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sat, 7 Jan 2023 14:13:19 -0500
Subject: [PATCH 11/36] feat: implement fileSize and fieldSize limits

---
 lib/formdata/parser.js              | 70 ++++++++++++++++++++++++-----
 test/busboy/test-types-multipart.js |  4 +-
 2 files changed, 62 insertions(+), 12 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 4266c4a77a8..facf41c14cc 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -27,7 +27,16 @@ class FormDataParser extends Writable {
       chunks: [],
       length: 0
     },
-    complete: false
+    complete: false,
+    limits: {
+      fieldNameSize: 0,
+      fieldSize: 0,
+      fields: 0,
+      fileSize: 0,
+      files: 0,
+      parts: 0,
+      headerPairs: 0
+    }
   }
 
   #opts = {}
@@ -50,6 +59,15 @@ class FormDataParser extends Writable {
     if (opts) {
       this.#opts.defCharset = opts.defCharset ?? 'utf8'
       this.#opts.defParamCharset = opts.defParamCharset ?? 'utf8'
+      this.#opts.limits = {
+        fieldNameSize: opts.limits?.fieldNameSize ?? 100,
+        fieldSize: opts.limits?.fieldSize ?? 1000 * 1000,
+        fields: opts.limits?.fields ?? Infinity,
+        fileSize: opts.limits?.fileSize ?? Infinity,
+        files: opts.limits?.files ?? Infinity,
+        parts: opts.limits?.parts ?? Infinity,
+        headerPairs: opts.limits?.headerPairs ?? 2000
+      }
     }
   }
 
@@ -263,26 +281,58 @@ class FormDataParser extends Writable {
           const rest = buffer.subarray(idx)
           const chunk = buffer.subarray(0, idx - 4) // remove \r\n--
 
-          if (this.#info.stream !== null) {
-            this.#info.stream.push(chunk)
+          if (
+            this.#info.stream !== null &&
+            this.#info.limits.fileSize < this.#opts.limits.fileSize
+          ) {
+            const limit = this.#opts.limits.fileSize
+            const current = this.#info.limits.fileSize
+            const length = chunk.length
+
+            let limitedChunk
+
+            if (current + length >= limit) {
+              // If the limit is reached
+              limitedChunk = chunk.subarray(0, limit - (current + length))
+
+              this.#info.stream.emit('limit') // TODO: arguments?
+              this.#info.stream.truncated = true
+            } else {
+              limitedChunk = chunk
+            }
+
+            this.#info.limits.fileSize += length
+            this.#info.stream.push(limitedChunk)
             this.#info.stream.destroy()
-          } else {
+          } else if (this.#info.limits.fieldSize < this.#opts.limits.fieldSize) {
             const { headers, attributes, body } = this.#info
 
             body.chunks.push(chunk)
             body.length += chunk.length
 
-            const fullBody = new TextDecoder('utf-8', { fatal: true }).decode(
-              Buffer.concat(body.chunks, body.length)
-            )
+            let fullBody = Buffer.concat(body.chunks, body.length)
+
+            const limit = this.#opts.limits.fieldSize
+            const current = this.#info.limits.fieldSize
+
+            let valueTruncated = false
+
+            if (current + body.length >= limit) {
+              // If the limit is reached
+              fullBody = fullBody.subarray(0, limit - (current + body.length))
+
+              valueTruncated = true
+            }
+
+            this.#info.limits.fieldSize += body.length
 
             this.emit(
               'field',
               attributes.name,
-              fullBody,
+              new TextDecoder('utf-8', { fatal: true }).decode(fullBody),
               {
-                nameTruncated: false, // todo
-                valueTruncated: false, // todo
+                nameTruncated: false,
+                valueTruncated,
                 encoding: headers['content-transfer-encoding'] ?? '7bit',
                 mimeType: headers['content-type'] ?? 'text/plain'
               }
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index 4e48e8e029a..7a4272ef1e2 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -931,7 +931,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 3)) {
+for (const test of tests.slice(0, 4)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1013,7 @@ for (const test of tests.slice(0, 3)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 3)) {
+for (let test of tests.slice(0, 4)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From 5629f71687cd66d55d8811b2c7e87c5fe71ba3b7 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sat, 7 Jan 2023 17:37:09 -0500
Subject: [PATCH 12/36] feat: implement files limit

---
 lib/formdata/parser.js              | 40 +++++++++++++++++++----------
 test/busboy/test-types-multipart.js |  4 +--
 2 files changed, 28 insertions(+), 16 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index facf41c14cc..350fd91d252 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -56,18 +56,16 @@ class FormDataParser extends Writable {
 
     this.#boundary = Buffer.from(mimeType.parameters.get('boundary'))
 
-    if (opts) {
-      this.#opts.defCharset = opts.defCharset ?? 'utf8'
-      this.#opts.defParamCharset = opts.defParamCharset ?? 'utf8'
-      this.#opts.limits = {
-        fieldNameSize: opts.limits?.fieldNameSize ?? 100,
-        fieldSize: opts.limits?.fieldSize ?? 1000 * 1000,
-        fields: opts.limits?.fields ?? Infinity,
-        fileSize: opts.limits?.fileSize ?? Infinity,
-        files: opts.limits?.files ?? Infinity,
-        parts: opts.limits?.parts ?? Infinity,
-        headerPairs: opts.limits?.headerPairs ?? 2000
-      }
+    this.#opts.defCharset = opts?.defCharset ?? 'utf8'
+    this.#opts.defParamCharset = opts?.defParamCharset ?? 'utf8'
+    this.#opts.limits = {
+      fieldNameSize: opts?.limits?.fieldNameSize ?? 100,
+      fieldSize: opts?.limits?.fieldSize ?? 1000 * 1000,
+      fields: opts?.limits?.fields ?? Infinity,
+      fileSize: opts?.limits?.fileSize ?? Infinity,
+      files: opts?.limits?.files ?? Infinity,
+      parts: opts?.limits?.parts ?? Infinity,
+      headerPairs: opts?.limits?.headerPairs ?? 2000
     }
   }
 
@@ -199,6 +197,11 @@ class FormDataParser extends Writable {
           attributes.filename !== undefined ||
           receivedHeaders['content-type'] === 'application/octet-stream'
         ) {
+          if (this.#info.limits.files >= this.#opts.limits.files) {
+            this.#info.skipPart = 'file'
+            continue
+          }
+
           this.#info.stream = new FileStream()
           this.#info.stream.truncated = false // TODO
 
@@ -281,9 +284,11 @@ class FormDataParser extends Writable {
           const rest = buffer.subarray(idx)
           const chunk = buffer.subarray(0, idx - 4) // remove \r\n--
 
+          // If the current part is a file
           if (
             this.#info.stream !== null &&
-            this.#info.limits.fileSize < this.#opts.limits.fileSize
+            this.#info.limits.fileSize < this.#opts.limits.fileSize &&
+            !this.#info.skipPart
           ) {
             const limit = this.#opts.limits.fileSize
             const current = this.#info.limits.fileSize
@@ -301,10 +306,15 @@ class FormDataParser extends Writable {
               limitedChunk = chunk
             }
 
+            this.#info.limits.files += 1
             this.#info.limits.fileSize += length
+
             this.#info.stream.push(limitedChunk)
             this.#info.stream.destroy()
-          } else if (this.#info.limits.fieldSize < this.#opts.limits.fieldSize) {
+          } else if (
+            this.#info.limits.fieldSize < this.#opts.limits.fieldSize &&
+            !this.#info.skipPart
+          ) {
             const { headers, attributes, body } = this.#info
 
             body.chunks.push(chunk)
@@ -340,6 +350,8 @@ class FormDataParser extends Writable {
 
             body.chunks.length = 0
             body.length = 0
+          } else if (this.#info.skipPart === 'file') {
+            this.emit('filesLimit')
           }
 
           this.#buffers.unshift(rest)
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index 7a4272ef1e2..958f093034e 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -931,7 +931,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 4)) {
+for (const test of tests.slice(0, 5)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1013,7 @@ for (const test of tests.slice(0, 4)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 4)) {
+for (let test of tests.slice(0, 5)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From 084a5e356879bdb75ba35d27c677c59b2cc91667 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sat, 7 Jan 2023 17:50:32 -0500
Subject: [PATCH 13/36] fix: parse filename base and fix filename w/
 backslashes

---
 lib/formdata/parser.js              | 17 ++++++++++-------
 lib/formdata/util.js                | 25 +++++++++++++++++++++++++
 test/busboy/test-types-multipart.js |  4 ++--
 3 files changed, 37 insertions(+), 9 deletions(-)
 create mode 100644 lib/formdata/util.js

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 350fd91d252..fd5b766a5bf 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -1,12 +1,13 @@
 'use strict'
 
 const { Writable } = require('stream')
+const { basename } = require('path')
 const { states, chars, headerStates, emptyBuffer } = require('./constants')
 const { FileStream } = require('./filestream')
+const { collectHTTPQuotedStringLenient } = require('./util')
 const {
   parseMIMEType,
-  collectASequenceOfCodePoints,
-  collectAnHTTPQuotedString
+  collectASequenceOfCodePoints
 } = require('../fetch/dataURL')
 
 class FormDataParser extends Writable {
@@ -510,12 +511,14 @@ class FormDataParser extends Writable {
 
           const attribute = collected.toString(this.#opts.defParamCharset)
           const equalIdx = attribute.indexOf('=')
-          const name = attribute.slice(0, equalIdx).trim()
-          const value = attribute[equalIdx + 1] === '"'
-            ? collectAnHTTPQuotedString(attribute.slice(equalIdx + 1), { position: 0 }, true)
-            : attribute.slice(equalIdx + 1)
+          const name = attribute.slice(0, equalIdx).trim().toLowerCase()
+          const value = collectHTTPQuotedStringLenient(attribute.slice(equalIdx + 1))
 
-          attributes[name] = value
+          if (name === 'filename') {
+            attributes[name] = basename(value)
+          } else {
+            attributes[name] = value
+          }
 
           if (buffer[position.position] === chars.cr) {
             break
diff --git a/lib/formdata/util.js b/lib/formdata/util.js
new file mode 100644
index 00000000000..5bf619903c9
--- /dev/null
+++ b/lib/formdata/util.js
@@ -0,0 +1,25 @@
+'use strict'
+
+const { collectASequenceOfCodePoints } = require('../fetch/dataURL')
+
+/**
+ * Collect a string inside of quotes. Unlike
+ * `collectAnHTTPQuotedString` from dataURL utilities,
+ * this one does not remove backslashes.
+ * @param {string} str
+ */
+function collectHTTPQuotedStringLenient (str) {
+  if (str[0] !== '"') {
+    return str
+  }
+
+  return collectASequenceOfCodePoints(
+    (char) => char !== '"',
+    str,
+    { position: 1 }
+  )
+}
+
+module.exports = {
+  collectHTTPQuotedStringLenient
+}
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index 958f093034e..9bdf81eb1f9 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -931,7 +931,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 5)) {
+for (const test of tests.slice(0, 7)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1013,7 @@ for (const test of tests.slice(0, 5)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 5)) {
+for (let test of tests.slice(0, 7)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From 771fa9de8de4036ba6c948980446926ddbd0d49b Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sat, 7 Jan 2023 17:55:24 -0500
Subject: [PATCH 14/36] fix: only parse path if preservePath is false

---
 lib/formdata/parser.js              | 3 ++-
 test/busboy/test-types-multipart.js | 4 ++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index fd5b766a5bf..f06ed5378ab 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -59,6 +59,7 @@ class FormDataParser extends Writable {
 
     this.#opts.defCharset = opts?.defCharset ?? 'utf8'
     this.#opts.defParamCharset = opts?.defParamCharset ?? 'utf8'
+    this.#opts.preservePath = !!opts?.preservePath
     this.#opts.limits = {
       fieldNameSize: opts?.limits?.fieldNameSize ?? 100,
       fieldSize: opts?.limits?.fieldSize ?? 1000 * 1000,
@@ -515,7 +516,7 @@ class FormDataParser extends Writable {
           const value = collectHTTPQuotedStringLenient(attribute.slice(equalIdx + 1))
 
           if (name === 'filename') {
-            attributes[name] = basename(value)
+            attributes[name] = this.#opts.preservePath ? value : basename(value)
           } else {
             attributes[name] = value
           }
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index 9bdf81eb1f9..18fa9b313f3 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -931,7 +931,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 7)) {
+for (const test of tests.slice(0, 8)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1013,7 @@ for (const test of tests.slice(0, 7)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 7)) {
+for (let test of tests.slice(0, 8)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From 8301ce896bbe24a477f2f53a930b5eb9672f4bfc Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sat, 7 Jan 2023 18:29:56 -0500
Subject: [PATCH 15/36] fix: filename parsing and filename* parsing

---
 lib/formdata/parser.js              | 54 ++++++++++++++++++++++-------
 lib/formdata/util.js                | 16 ++++++++-
 test/busboy/test-types-multipart.js |  4 +--
 3 files changed, 59 insertions(+), 15 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index f06ed5378ab..88bd4f6ad43 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -4,10 +4,14 @@ const { Writable } = require('stream')
 const { basename } = require('path')
 const { states, chars, headerStates, emptyBuffer } = require('./constants')
 const { FileStream } = require('./filestream')
-const { collectHTTPQuotedStringLenient } = require('./util')
+const {
+  collectHTTPQuotedStringLenient,
+  findCharacterType
+} = require('./util')
 const {
   parseMIMEType,
-  collectASequenceOfCodePoints
+  collectASequenceOfCodePoints,
+  stringPercentDecode
 } = require('../fetch/dataURL')
 
 class FormDataParser extends Writable {
@@ -114,6 +118,8 @@ class FormDataParser extends Writable {
           return callback()
         }
 
+        this.#info.skipPart = ''
+
         const bytes = this.consume(this.#boundary.length)
         const nextBytes = this.consume(2) // \r\n OR --
 
@@ -195,8 +201,11 @@ class FormDataParser extends Writable {
           Buffer.concat(headers, headersLength)
         )
 
-        if (
+        if (this.#info.skipPart === 'missing content-disposition') {
+          continue
+        } else if (
           attributes.filename !== undefined ||
+          attributes['filename*'] !== undefined ||
           receivedHeaders['content-type'] === 'application/octet-stream'
         ) {
           if (this.#info.limits.files >= this.#opts.limits.files) {
@@ -212,9 +221,9 @@ class FormDataParser extends Writable {
             attributes.name, // name is a required attribute
             this.#info.stream,
             {
-              filename: attributes.filename ?? '',
+              filename: attributes.filename ?? attributes['filename*'] ?? '',
               encoding: receivedHeaders['content-transfer-encoding'] ?? '7bit',
-              mimeType: receivedHeaders['content-type'] ?? 'application/octet-stream'
+              mimeType: receivedHeaders['content-type'] || 'application/octet-stream'
             }
           )
         } else {
@@ -346,7 +355,7 @@ class FormDataParser extends Writable {
                 nameTruncated: false,
                 valueTruncated,
                 encoding: headers['content-transfer-encoding'] ?? '7bit',
-                mimeType: headers['content-type'] ?? 'text/plain'
+                mimeType: headers['content-type'] || 'text/plain'
               }
             )
 
@@ -515,8 +524,32 @@ class FormDataParser extends Writable {
           const name = attribute.slice(0, equalIdx).trim().toLowerCase()
           const value = collectHTTPQuotedStringLenient(attribute.slice(equalIdx + 1))
 
-          if (name === 'filename') {
-            attributes[name] = this.#opts.preservePath ? value : basename(value)
+          if (name === 'filename*') {
+            // https://www.rfc-editor.org/rfc/rfc6266#section-4.3
+
+            // This attribute is split into 3 parts:
+            // 1. The character type (ie. utf-8)
+            // 2. The optional language tag (ie. en or ''). This value is in single quotes.
+            // 3. The percent encoded name.
+
+            const quote1 = value.indexOf('\'')
+            const quote2 = value.indexOf('\'', quote1 + 1)
+
+            const characterType = findCharacterType(value.slice(0, quote1))
+            const percentEncoded = value.slice(quote2 + 1)
+
+            attributes['filename*'] = new TextDecoder(characterType).decode(
+              stringPercentDecode(percentEncoded)
+            )
+
+            attributes.filename ??= undefined
+          } else if (name === 'filename') {
+            // Therefore, when both
+            // "filename" and "filename*" are present in a single header field
+            // value, recipients SHOULD pick "filename*" and ignore "filename".
+            if (!attributes['filename*']) {
+              attributes[name] = this.#opts.preservePath ? value : basename(value)
+            }
           } else {
             attributes[name] = value
           }
@@ -531,13 +564,10 @@ class FormDataParser extends Writable {
     }
 
     // Validate the header values here
-    // TODO: match busboy's behavior with error handling
     if (headers['content-disposition'] !== 'form-data') {
-      this.destroy(new Error('received invalid content-disposition header'))
-      return
+      this.#info.skipPart = 'missing content-disposition'
     } else if (attributes.name === undefined) {
       this.destroy(new Error('Content-Disposition had no name attribute'))
-      return
     }
 
     return { headers, attributes }
diff --git a/lib/formdata/util.js b/lib/formdata/util.js
index 5bf619903c9..56edb482688 100644
--- a/lib/formdata/util.js
+++ b/lib/formdata/util.js
@@ -20,6 +20,20 @@ function collectHTTPQuotedStringLenient (str) {
   )
 }
 
+function findCharacterType (type) {
+  switch (type) {
+    case 'utf8':
+    case 'utf-8':
+      return 'utf-8'
+    case 'latin1':
+    case 'ascii':
+      return 'latin1'
+    default:
+      return type.toLowerCase()
+  }
+}
+
 module.exports = {
-  collectHTTPQuotedStringLenient
+  collectHTTPQuotedStringLenient,
+  findCharacterType
 }
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index 18fa9b313f3..d65b3c6bcb9 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -931,7 +931,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 8)) {
+for (const test of tests.slice(0, 10)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1013,7 @@ for (const test of tests.slice(0, 8)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 8)) {
+for (let test of tests.slice(0, 10)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From 4c40486abe6bd77b94a182b8067d389a49d8f40d Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sun, 8 Jan 2023 10:39:54 -0500
Subject: [PATCH 16/36] fix: actively parse headers, rather than lazily

---
 lib/formdata/parser.js | 95 ++++++++++++++++++++----------------------
 1 file changed, 46 insertions(+), 49 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 88bd4f6ad43..c0b48ff3bc1 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -26,7 +26,6 @@ class FormDataParser extends Writable {
 
   #info = {
     headerState: headerStates.DEFAULT,
-    rawHeaders: null,
     stream: null,
     body: {
       chunks: [],
@@ -41,6 +40,9 @@ class FormDataParser extends Writable {
       files: 0,
       parts: 0,
       headerPairs: 0
+    },
+    headers: {
+      attributes: {}
     }
   }
 
@@ -153,22 +155,16 @@ class FormDataParser extends Writable {
         let bytesToRemove = 0
 
         done: { // eslint-disable-line no-labels
-          for (const buffer of this.#buffers) {
-            for (const byte of buffer) {
-              const state = this.#info.headerState
+          this.#info.headerState = headerStates.DEFAULT
 
-              if (byte !== chars.cr && byte !== chars.lf) {
-                // Some pieces may have multiple headers, separated by \r\n.
-                // We need to also consider those bytes.
-                if (state === headerStates.FIRST) { // \r
-                  bytesToRemove += 1
-                } else if (state === headerStates.SECOND) { // \r\n
-                  bytesToRemove += 2
-                }
+          for (let j = 0; j < this.#buffers.length; j++) {
+            const buffer = this.#buffers[j]
 
-                bytesToRemove += 1
-                this.#info.headerState = headerStates.DEFAULT
-              } else if (byte === chars.cr && state === headerStates.DEFAULT) {
+            for (let i = 0; i < buffer.length; i++) {
+              const byte = buffer[i]
+              const state = this.#info.headerState
+
+              if (byte === chars.cr && state === headerStates.DEFAULT) {
                 this.#info.headerState = headerStates.FIRST
               } else if (byte === chars.lf && state === headerStates.FIRST) {
                 this.#info.headerState = headerStates.SECOND
@@ -177,36 +173,49 @@ class FormDataParser extends Writable {
               } else if (byte === chars.lf && state === headerStates.THIRD) {
                 // Got \r\n\r\n which marks the end of the headers.
                 this.#state = states.READ_BODY
+                bytesToRemove += i
+
+                const removed = this.consume(bytesToRemove - 3) // remove \r\n\r
+
+                this.#parseRawHeaders(removed)
+                this.consume(4)
 
                 break done // eslint-disable-line no-labels
+              } else {
+                this.#info.headerState = headerStates.DEFAULT
+
+                if (state === headerStates.SECOND) {
+                  if (bytesToRemove === 0) {
+                    continue
+                  }
+
+                  const removed = this.consume(bytesToRemove - 2) // remove \r\n
+
+                  this.#parseRawHeaders(removed)
+                  this.consume(2)
+                  bytesToRemove -= removed.length
+                }
               }
             }
+
+            bytesToRemove += buffer.length
           }
 
           return callback()
         }
 
-        const headers = this.#info.rawHeaders ?? []
-        let headersLength = 0
-
-        if (bytesToRemove > 0) {
-          const removed = this.consume(bytesToRemove)
-
-          headers.push(removed)
-          headersLength += removed.length
-        }
-
-        this.consume(4) // remove \r\n\r\n
-        const { headers: receivedHeaders, attributes } = this.#parseRawHeaders(
-          Buffer.concat(headers, headersLength)
-        )
+        const { attributes, ...headers } = this.#info.headers
 
-        if (this.#info.skipPart === 'missing content-disposition') {
-          continue
+        if (
+          headers['content-disposition'] !== 'form-data' ||
+          !attributes.name
+        ) {
+          // https://www.rfc-editor.org/rfc/rfc7578#section-4.2
+          this.#info.skipPart = 'invalid content-disposition'
         } else if (
           attributes.filename !== undefined ||
           attributes['filename*'] !== undefined ||
-          receivedHeaders['content-type'] === 'application/octet-stream'
+          headers['content-type'] === 'application/octet-stream'
         ) {
           if (this.#info.limits.files >= this.#opts.limits.files) {
             this.#info.skipPart = 'file'
@@ -222,13 +231,10 @@ class FormDataParser extends Writable {
             this.#info.stream,
             {
               filename: attributes.filename ?? attributes['filename*'] ?? '',
-              encoding: receivedHeaders['content-transfer-encoding'] ?? '7bit',
-              mimeType: receivedHeaders['content-type'] || 'application/octet-stream'
+              encoding: headers['content-transfer-encoding'] ?? '7bit',
+              mimeType: headers['content-type'] || 'application/octet-stream'
             }
           )
-        } else {
-          this.#info.headers = receivedHeaders
-          this.#info.attributes = attributes
         }
       } else if (this.#state === states.READ_BODY) {
         // A part's body can contain CRLFs so they cannot be used to
@@ -326,7 +332,7 @@ class FormDataParser extends Writable {
             this.#info.limits.fieldSize < this.#opts.limits.fieldSize &&
             !this.#info.skipPart
           ) {
-            const { headers, attributes, body } = this.#info
+            const { headers: { attributes, ...headers }, body } = this.#info
 
             body.chunks.push(chunk)
             body.length += chunk.length
@@ -420,12 +426,10 @@ class FormDataParser extends Writable {
    * @param {Buffer} buffer
    */
   #parseRawHeaders (buffer) {
-    this.#info.rawHeaders = null
-
     // https://www.rfc-editor.org/rfc/rfc7578#section-4.8
 
-    const headers = {}
-    const attributes = {}
+    const headers = this.#info.headers
+    const attributes = this.#info.headers.attributes
 
     const position = { position: 0 }
 
@@ -563,13 +567,6 @@ class FormDataParser extends Writable {
       position.position += 2 // skip \r\n
     }
 
-    // Validate the header values here
-    if (headers['content-disposition'] !== 'form-data') {
-      this.#info.skipPart = 'missing content-disposition'
-    } else if (attributes.name === undefined) {
-      this.destroy(new Error('Content-Disposition had no name attribute'))
-    }
-
     return { headers, attributes }
   }
 }

From 6c1b276d6e38c48ce5134faeaced92385bd1f34e Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sun, 8 Jan 2023 16:49:11 -0500
Subject: [PATCH 17/36] fix(finally): validate header name and fix parser
 issues

---
 lib/formdata/parser.js              | 30 ++++++++++++++++++++++-------
 test/busboy/test-types-multipart.js |  4 ++--
 2 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index c0b48ff3bc1..d446f40ebbb 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -185,15 +185,17 @@ class FormDataParser extends Writable {
                 this.#info.headerState = headerStates.DEFAULT
 
                 if (state === headerStates.SECOND) {
-                  if (bytesToRemove === 0) {
+                  const removed = this.consume(bytesToRemove + i - 2)
+
+                  if (this.#info.skipPart) {
+                    // If we are meant to skip this part, we shouldn't
+                    // parse the headers. We just need to consume the bytes.
                     continue
                   }
 
-                  const removed = this.consume(bytesToRemove - 2) // remove \r\n
-
                   this.#parseRawHeaders(removed)
                   this.consume(2)
-                  bytesToRemove -= removed.length
+                  bytesToRemove -= removed.length + 2
                 }
               }
             }
@@ -207,8 +209,11 @@ class FormDataParser extends Writable {
         const { attributes, ...headers } = this.#info.headers
 
         if (
-          headers['content-disposition'] !== 'form-data' ||
-          !attributes.name
+          !this.#info.skipPart &&
+          (
+            headers['content-disposition'] !== 'form-data' ||
+            !attributes.name
+          )
         ) {
           // https://www.rfc-editor.org/rfc/rfc7578#section-4.2
           this.#info.skipPart = 'invalid content-disposition'
@@ -440,8 +445,19 @@ class FormDataParser extends Writable {
         position
       )
 
-      // Invalid header; has no value
       if (position.position >= buffer.length) {
+        // Invalid header; doesn't contain a delimiter
+        break
+      } else if (nameBuffer.length === 0) {
+        // https://www.rfc-editor.org/rfc/rfc9110.html#section-5.1-2
+        // field-name     = token
+        // tchar = "!" / "#" / "$" / "%" / "&" / "'" / "*" / "+" / "-" / "." /
+        // "^" / "_" / "`" / "|" / "~" / DIGIT / ALPHA
+        // token = 1*tchar
+
+        // The field name MUST be at least 1 character long.
+        this.#info.skipPart = 'malformed part header'
+        this.emit('error', new Error('Malformed part header'))
         break
       }
 
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index d65b3c6bcb9..0122c7caf89 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -931,7 +931,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 10)) {
+for (const test of tests.slice(0, 11)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1013,7 @@ for (const test of tests.slice(0, 10)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 10)) {
+for (let test of tests.slice(0, 11)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From 601a4ea1501d285c8d6fe7818dfae916edd3125b Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sun, 8 Jan 2023 20:03:52 -0500
Subject: [PATCH 18/36] fix: send leftover buffers to filestream on destroy,
 cleanup

---
 lib/formdata/parser.js              | 17 +++++++++++++++++
 test/busboy/test-types-multipart.js |  4 ++--
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index d446f40ebbb..7f1209aa4c9 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -97,6 +97,21 @@ class FormDataParser extends Writable {
     }
   }
 
+  _destroy (err, cb) {
+    if (this.#info.stream) {
+      // Push any leftover buffers to the filestream
+      for (const leftover of this.#buffers) {
+        this.#info.stream.push(leftover)
+      }
+
+      // Emit an error event on the file stream if there is one
+      this.#info.stream.destroy(err)
+      this.#info.stream = null
+    }
+
+    cb(err)
+  }
+
   /**
    * @param {() => void} callback
    */
@@ -227,6 +242,8 @@ class FormDataParser extends Writable {
             continue
           }
 
+          // End the active stream if there is one
+          this.#info.stream?.push(null)
           this.#info.stream = new FileStream()
           this.#info.stream.truncated = false // TODO
 
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index 0122c7caf89..7cd440e2f19 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -931,7 +931,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 11)) {
+for (const test of tests.slice(0, 15)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1013,7 @@ for (const test of tests.slice(0, 11)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 11)) {
+for (let test of tests.slice(0, 15)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From cd6dd4bd2ce31e755f01796d9b7884e15e89d207 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sun, 8 Jan 2023 20:09:12 -0500
Subject: [PATCH 19/36] fix: content-type headers cannot contain ;

---
 lib/formdata/parser.js              | 12 ++++--------
 test/busboy/test-types-multipart.js |  4 ++--
 2 files changed, 6 insertions(+), 10 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 7f1209aa4c9..132fe702011 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -511,14 +511,10 @@ class FormDataParser extends Writable {
 
       const value = collectASequenceOfCodePoints(
         (char) => {
-          if (name === 'content-disposition') {
-            // mimetypes (ie. from a content-type header) can have
-            // a semicolon in it. In that case, we want to read the
-            // entire value in, not just until we reach a semicolon
-            return char !== chars[';']
-          }
-
-          return char !== chars.cr && buffer[position.position + 1] !== chars.lf
+          return (
+            char !== chars[';'] &&
+            (char !== chars.cr && buffer[position.position + 1] !== chars.lf)
+          )
         },
         buffer,
         position
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index 7cd440e2f19..4549d712707 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -931,7 +931,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 15)) {
+for (const test of tests.slice(0, 16)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1013,7 @@ for (const test of tests.slice(0, 15)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 15)) {
+for (let test of tests.slice(0, 16)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From 52b4b0a37e335a395ac8815d21dedf8d5f3522e7 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sun, 8 Jan 2023 20:45:40 -0500
Subject: [PATCH 20/36] enable test

---
 test/busboy/test-types-multipart.js | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index 4549d712707..30c045aaabc 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -618,7 +618,17 @@ const tests = [
         info: {
           filename: 'notes.txt',
           encoding: '7bit',
-          mimeType: 'text/plain'
+          // TODO(@KhafraDev): This behavior is correct (the value should be text/plain),
+          // but the added complexity of removing leading/trailing whitespace would make
+          // this very challenging. Note that a header field value must not be empty,
+          // which will be used to allow such headers to be parsed.
+          //
+          // https://www.rfc-editor.org/rfc/rfc9110.html#section-5.5
+          // A field value does not include leading or trailing whitespace.  When
+          // a specific version of HTTP allows such whitespace to appear in a
+          // message, a field parsing implementation MUST exclude such whitespace
+          // prior to evaluating the field value.
+          mimeType: 'application/octet-stream' // 'text/plain'
         },
         limited: false
       }
@@ -931,7 +941,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 16)) {
+for (const test of tests.slice(0, 18)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1023,7 @@ for (const test of tests.slice(0, 16)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 16)) {
+for (let test of tests.slice(0, 18)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From d33ac7e3f01f9403073027442302040859f2149a Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Mon, 9 Jan 2023 13:55:30 -0500
Subject: [PATCH 21/36] fix: content-type header with leading whitespace

---
 lib/formdata/parser.js              | 11 +++++++++++
 test/busboy/test-types-multipart.js | 12 +-----------
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 132fe702011..f06e7869e55 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -191,6 +191,17 @@ class FormDataParser extends Writable {
                 bytesToRemove += i
 
                 const removed = this.consume(bytesToRemove - 3) // remove \r\n\r
+                const headers = this.#info.headers
+
+                // This is a very lazy implementation.
+                if ('content-type' in headers && headers['content-type'].length === 0) {
+                  const mimeUnparsed = removed.toString(this.#opts.defCharset)
+                  const mimeType = parseMIMEType(mimeUnparsed)
+
+                  if (mimeType !== 'failure') {
+                    headers['content-type'] = mimeType.essence
+                  }
+                }
 
                 this.#parseRawHeaders(removed)
                 this.consume(4)
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index 30c045aaabc..eaab0f00831 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -618,17 +618,7 @@ const tests = [
         info: {
           filename: 'notes.txt',
           encoding: '7bit',
-          // TODO(@KhafraDev): This behavior is correct (the value should be text/plain),
-          // but the added complexity of removing leading/trailing whitespace would make
-          // this very challenging. Note that a header field value must not be empty,
-          // which will be used to allow such headers to be parsed.
-          //
-          // https://www.rfc-editor.org/rfc/rfc9110.html#section-5.5
-          // A field value does not include leading or trailing whitespace.  When
-          // a specific version of HTTP allows such whitespace to appear in a
-          // message, a field parsing implementation MUST exclude such whitespace
-          // prior to evaluating the field value.
-          mimeType: 'application/octet-stream' // 'text/plain'
+          mimeType: 'text/plain'
         },
         limited: false
       }

From a2bcfd60555fc1e9c5ff473ce459f8086ec09c70 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Mon, 9 Jan 2023 14:07:07 -0500
Subject: [PATCH 22/36] fix: don't emit field event w/o listeners

---
 lib/formdata/parser.js | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index f06e7869e55..2f7efd6f679 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -89,7 +89,7 @@ class FormDataParser extends Writable {
   }
 
   /**
-   * @param {(error?: Error | null) => void)} cb
+   * @param {((error?: Error | null) => void)} cb
    */
   _final (cb) {
     if (!this.#info.complete) {
@@ -97,6 +97,10 @@ class FormDataParser extends Writable {
     }
   }
 
+  /**
+   * @param {Error|null} err
+   * @param {((error?: Error|null) => void)} cb
+   */
   _destroy (err, cb) {
     if (this.#info.stream) {
       // Push any leftover buffers to the filestream
@@ -363,7 +367,8 @@ class FormDataParser extends Writable {
             this.#info.stream.destroy()
           } else if (
             this.#info.limits.fieldSize < this.#opts.limits.fieldSize &&
-            !this.#info.skipPart
+            !this.#info.skipPart &&
+            this.listenerCount('field') > 0
           ) {
             const { headers: { attributes, ...headers }, body } = this.#info
 

From 82ea7a3ea98cd7b2ca3e4849ec8c8c3d9aa52e9b Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Mon, 9 Jan 2023 14:07:24 -0500
Subject: [PATCH 23/36] fix: don't emit field event w/o listeners

---
 test/busboy/test-types-multipart.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index eaab0f00831..df99f041465 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -931,7 +931,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 18)) {
+for (const test of tests.slice(0, 19)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1013,7 @@ for (const test of tests.slice(0, 18)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 18)) {
+for (let test of tests.slice(0, 19)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From 0d9905456b06211586ef545ea8bed870b8ad5681 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Mon, 9 Jan 2023 14:18:42 -0500
Subject: [PATCH 24/36] feat: implement parts limit

---
 lib/formdata/parser.js              | 6 ++++++
 test/busboy/test-types-multipart.js | 4 ++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 2f7efd6f679..3e9702dd804 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -158,8 +158,14 @@ class FormDataParser extends Writable {
 
           this.destroy(new Error('Boundary did not end with CRLF'))
           return
+        } else if (this.#info.limits.parts >= this.#opts.limits.parts) {
+          this.emit('partsLimit')
+          this.#info.skipPart = 'partsLimit'
+          this.#state = states.READ_BODY
+          continue
         }
 
+        this.#info.limits.parts++
         this.#state = states.READ_HEADERS
       } else if (this.#state === states.READ_HEADERS) {
         // There can be an arbitrary amount of headers and each one has an
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index df99f041465..1051f0e6169 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -931,7 +931,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 19)) {
+for (const test of tests.slice(0, 20)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1013,7 @@ for (const test of tests.slice(0, 19)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 19)) {
+for (let test of tests.slice(0, 20)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From 50669a6d2642083c728db3bfb8e3468aaf294c74 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Mon, 9 Jan 2023 14:28:48 -0500
Subject: [PATCH 25/36] feat: implement fields limit

---
 lib/formdata/parser.js              | 18 ++++++++++++++++++
 test/busboy/test-types-multipart.js |  4 ++--
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 3e9702dd804..a9331671784 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -376,6 +376,23 @@ class FormDataParser extends Writable {
             !this.#info.skipPart &&
             this.listenerCount('field') > 0
           ) {
+            if (this.#info.limits.fields >= this.#opts.limits.fields) {
+              this.#info.skipPart = 'fieldsLimit'
+              this.emit('fieldsLimit')
+
+              this.#state = states.BOUNDARY
+
+              // Remove all body chunks for the current field
+              this.#info.body.chunks.length = 0
+              this.#info.body.length = 0
+
+              // Add the rest of the bytes back to the buffer to parse
+              this.#buffers.unshift(rest)
+              this.#byteOffset += rest.length
+
+              continue
+            }
+
             const { headers: { attributes, ...headers }, body } = this.#info
 
             body.chunks.push(chunk)
@@ -409,6 +426,7 @@ class FormDataParser extends Writable {
               }
             )
 
+            this.#info.limits.fields++
             body.chunks.length = 0
             body.length = 0
           } else if (this.#info.skipPart === 'file') {
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index 1051f0e6169..25812016b9c 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -931,7 +931,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 20)) {
+for (const test of tests.slice(0, 21)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1013,7 @@ for (const test of tests.slice(0, 20)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 20)) {
+for (let test of tests.slice(0, 21)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From 5dd8b4532468518c2db1dfd4e0dfc71f167d0ac2 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Mon, 9 Jan 2023 17:01:24 -0500
Subject: [PATCH 26/36] fix: limit header length to 16 KiB

---
 lib/formdata/constants.js           | 5 ++++-
 lib/formdata/parser.js              | 9 ++++++++-
 test/busboy/test-types-multipart.js | 4 ++--
 3 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/lib/formdata/constants.js b/lib/formdata/constants.js
index 1bac7259edb..ac03c3839e2 100644
--- a/lib/formdata/constants.js
+++ b/lib/formdata/constants.js
@@ -27,9 +27,12 @@ const chars = {
 
 const emptyBuffer = Buffer.alloc(0)
 
+const maxHeaderLength = 16 * 1024
+
 module.exports = {
   states,
   chars,
   headerStates,
-  emptyBuffer
+  emptyBuffer,
+  maxHeaderLength
 }
diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index a9331671784..c0b6de5b53a 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -2,7 +2,7 @@
 
 const { Writable } = require('stream')
 const { basename } = require('path')
-const { states, chars, headerStates, emptyBuffer } = require('./constants')
+const { states, chars, headerStates, emptyBuffer, maxHeaderLength } = require('./constants')
 const { FileStream } = require('./filestream')
 const {
   collectHTTPQuotedStringLenient,
@@ -493,6 +493,13 @@ class FormDataParser extends Writable {
     const headers = this.#info.headers
     const attributes = this.#info.headers.attributes
 
+    if (buffer.length > maxHeaderLength) {
+      this.#info.skipPart = 'malformed part header'
+      this.emit('error', new Error('Malformed part header'))
+
+      return { headers, attributes }
+    }
+
     const position = { position: 0 }
 
     while (position.position < buffer.length) {
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index 25812016b9c..7249e329d16 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -931,7 +931,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 21)) {
+for (const test of tests.slice(0, 22)) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1013,7 @@ for (const test of tests.slice(0, 21)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 21)) {
+for (let test of tests.slice(0, 22)) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From 13f3cb5e0f914368ec16a1e189eaaabba955efcc Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Mon, 9 Jan 2023 17:41:49 -0500
Subject: [PATCH 27/36] omg every test passes

---
 lib/formdata/parser.js              | 11 ++++++++---
 test/busboy/test-types-multipart.js |  6 ++++--
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index c0b6de5b53a..dc79736c0d6 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -128,12 +128,17 @@ class FormDataParser extends Writable {
 
         const bytes = this.consume(2)
 
-        if (bytes[0] !== chars['-'] || bytes[1] !== chars['-']) {
-          this.destroy(new Error('FormData should start with --'))
+        if (
+          (bytes[0] !== chars['-'] || bytes[1] !== chars['-']) &&
+          (bytes[0] !== chars.cr || bytes[1] !== chars.lf)
+        ) {
+          this.destroy(new Error('FormData should start with -- or CRLF'))
           return
         }
 
-        this.#state = states.BOUNDARY
+        if (bytes[0] === chars['-']) {
+          this.#state = states.BOUNDARY
+        }
       } else if (this.#state === states.BOUNDARY) {
         if (this.#byteOffset < this.#boundary.length + 2) {
           return callback()
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index 7249e329d16..bf2edd65fd8 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -781,6 +781,8 @@ const tests = [
     what: 'Files limit'
   },
   {
+    // Note: this test is very slow because we need to write > 64 KiB
+    // of data one byte at a time.
     source: [
       ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
         'Content-Disposition: form-data; ' +
@@ -931,7 +933,7 @@ const tests = [
   }
 ]
 
-for (const test of tests.slice(0, 22)) {
+for (const test of tests) {
   active.set(test, 1)
 
   const { what, boundary, events, limits, preservePath, fileHwm } = test
@@ -1013,7 +1015,7 @@ for (const test of tests.slice(0, 22)) {
 }
 
 // Byte-by-byte versions
-for (let test of tests.slice(0, 22)) {
+for (let test of tests) {
   test = { ...test }
   test.what += ' (byte-by-byte)'
   active.set(test, 1)

From ed92a8246a8dd02ff3a4f4805c102c08e175150d Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Tue, 10 Jan 2023 00:36:28 -0500
Subject: [PATCH 28/36] fix: use path.win32.basename

---
 lib/formdata/parser.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index dc79736c0d6..4a823124418 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -1,7 +1,7 @@
 'use strict'
 
 const { Writable } = require('stream')
-const { basename } = require('path')
+const { win32: { basename } } = require('path')
 const { states, chars, headerStates, emptyBuffer, maxHeaderLength } = require('./constants')
 const { FileStream } = require('./filestream')
 const {

From dd01bd39d4a19ce2e67a62842c1c3a576a19d3af Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Tue, 10 Jan 2023 01:52:27 -0500
Subject: [PATCH 29/36] fix: add types & highwatermark options

---
 index.d.ts                |   1 +
 lib/formdata/parser.js    |   5 +-
 types/formdataparser.d.ts | 111 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 115 insertions(+), 2 deletions(-)
 create mode 100644 types/formdataparser.d.ts

diff --git a/index.d.ts b/index.d.ts
index d67de97241d..ba0f0909d72 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -21,6 +21,7 @@ export * from './types/fetch'
 export * from './types/file'
 export * from './types/filereader'
 export * from './types/formdata'
+export * from './types/formdataparser'
 export * from './types/diagnostics-channel'
 export * from './types/websocket'
 export * from './types/content-type'
diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 4a823124418..7c2c3c0ff57 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -49,7 +49,7 @@ class FormDataParser extends Writable {
   #opts = {}
 
   constructor (opts) {
-    super(opts)
+    super({ highWaterMark: opts?.highWaterMark })
 
     const contentType = opts.headers.get?.('content-type') ?? opts.headers['content-type']
     const mimeType = contentType ? parseMIMEType(contentType) : null
@@ -65,6 +65,7 @@ class FormDataParser extends Writable {
 
     this.#opts.defCharset = opts?.defCharset ?? 'utf8'
     this.#opts.defParamCharset = opts?.defParamCharset ?? 'utf8'
+    this.#opts.fileHwm = opts?.fileHwm
     this.#opts.preservePath = !!opts?.preservePath
     this.#opts.limits = {
       fieldNameSize: opts?.limits?.fieldNameSize ?? 100,
@@ -270,7 +271,7 @@ class FormDataParser extends Writable {
 
           // End the active stream if there is one
           this.#info.stream?.push(null)
-          this.#info.stream = new FileStream()
+          this.#info.stream = new FileStream({ highWaterMark: this.#opts.fileHwm })
           this.#info.stream.truncated = false // TODO
 
           this.emit(
diff --git a/types/formdataparser.d.ts b/types/formdataparser.d.ts
new file mode 100644
index 00000000000..ac2e8149c9f
--- /dev/null
+++ b/types/formdataparser.d.ts
@@ -0,0 +1,111 @@
+// @ts-check
+
+/// <reference types="node" />
+
+import { Writable, Readable } from 'stream'
+import { IncomingHttpHeaders } from 'http'
+import { Headers } from './fetch'
+
+export interface FormDataParserConfig {
+  headers: IncomingHttpHeaders | Headers
+  highWaterMark?: number
+  fileHwm?: number
+  defCharset?: string
+  defParamCharset?: string
+  preservePath?: boolean
+  limits?: {
+    fieldNameSize?: number
+    fieldSize?: number
+    fields?: number
+    fileSize?: number
+    files?: number
+    parts?: number
+    headerPairs?: number
+  }
+}
+
+interface FormDataParserErrors {
+  file: (
+    name: string,
+    stream: Readable,
+    info: {
+      fileName: string,
+      stream: FileStream,
+      info: {
+        filename: string,
+        encoding: string,
+        mimeType: string
+      }
+    }
+  ) => void
+
+  field: (
+    name: string,
+    value: string,
+    info: {
+      name: string,
+      data: string,
+      info: {
+        nameTruncated: boolean,
+        valueTruncated: boolean,
+        encoding: string,
+        mimeType: string
+      }
+    }
+  ) => void
+
+  partsLimit: () => void
+
+  filesLimit: () => void
+
+  fieldsLimit: () => void
+
+  limit: () => void
+
+  error: (error: Error) => void
+
+  close: () => void
+}
+
+export declare class FileStream extends Readable {}
+
+export declare class FormDataParser extends Writable {
+  constructor (opts: FormDataParserConfig)
+
+  private run (cb: (err?: Error) => void): void
+
+  addListener<
+    T extends keyof FormDataParserErrors
+  >(event: T, listener: FormDataParserErrors[T]): this
+  addListener(event: string | symbol, listener: (...args: any[]) => void): this
+
+  on<
+    T extends keyof FormDataParserErrors
+  >(event: T, listener: FormDataParserErrors[T]): this
+  on(event: string | symbol, listener: (...args: any[]) => void): this
+
+  once<
+    T extends keyof FormDataParserErrors
+  >(event: T, listener: FormDataParserErrors[T]): this
+  once(event: string | symbol, listener: (...args: any[]) => void): this
+
+  removeListener<
+    T extends keyof FormDataParserErrors
+  >(event: T, listener: FormDataParserErrors[T]): this
+  removeListener(event: string | symbol, listener: (...args: any[]) => void): this
+
+  off<
+    T extends keyof FormDataParserErrors
+  >(event: T, listener: FormDataParserErrors[T]): this
+  off(event: string | symbol, listener: (...args: any[]) => void): this
+
+  prependListener<
+    T extends keyof FormDataParserErrors
+  >(event: T, listener: FormDataParserErrors[T]): this
+  prependListener(event: string | symbol, listener: (...args: any[]) => void): this
+
+  prependOnceListener<
+    T extends keyof FormDataParserErrors
+  >(event: T, listener: FormDataParserErrors[T]): this
+  prependOnceListener(event: string | symbol, listener: (...args: any[]) => void): this
+}

From 787b679897583305f79c903b080fe64060a25ccc Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Tue, 10 Jan 2023 23:07:32 -0500
Subject: [PATCH 30/36] fix: speedup header parsing & bug fixes & nyc coverage

---
 lib/formdata/constants.js           |   5 +-
 lib/formdata/parser.js              | 153 +++++++++++++++-------------
 lib/formdata/textsearch.js          |  47 +++++++++
 lib/formdata/util.js                |  18 +++-
 package.json                        |   1 +
 test/busboy/test-types-multipart.js |   2 -
 6 files changed, 150 insertions(+), 76 deletions(-)
 create mode 100644 lib/formdata/textsearch.js

diff --git a/lib/formdata/constants.js b/lib/formdata/constants.js
index ac03c3839e2..ef8d2a80a26 100644
--- a/lib/formdata/constants.js
+++ b/lib/formdata/constants.js
@@ -27,6 +27,8 @@ const chars = {
 
 const emptyBuffer = Buffer.alloc(0)
 
+const crlfBuffer = Buffer.from('\r\n')
+
 const maxHeaderLength = 16 * 1024
 
 module.exports = {
@@ -34,5 +36,6 @@ module.exports = {
   chars,
   headerStates,
   emptyBuffer,
-  maxHeaderLength
+  maxHeaderLength,
+  crlfBuffer
 }
diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 7c2c3c0ff57..d4df1755d76 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -2,12 +2,15 @@
 
 const { Writable } = require('stream')
 const { win32: { basename } } = require('path')
-const { states, chars, headerStates, emptyBuffer, maxHeaderLength } = require('./constants')
+const { states, chars, headerStates, emptyBuffer, maxHeaderLength, crlfBuffer } = require('./constants')
 const { FileStream } = require('./filestream')
 const {
   collectHTTPQuotedStringLenient,
-  findCharacterType
+  findCharacterType,
+  hasHeaderValue,
+  isWhitespace
 } = require('./util')
+const { TextSearch } = require('./textsearch')
 const {
   parseMIMEType,
   collectASequenceOfCodePoints,
@@ -43,13 +46,19 @@ class FormDataParser extends Writable {
     },
     headers: {
       attributes: {}
-    }
+    },
+    headerEndSearch: new TextSearch(Buffer.from('\r\n\r\n')),
+    headerBuffersChecked: 0
   }
 
   #opts = {}
 
   constructor (opts) {
-    super({ highWaterMark: opts?.highWaterMark })
+    super({
+      highWaterMark: opts?.highWaterMark,
+      autoDestroy: true,
+      emitClose: true
+    })
 
     const contentType = opts.headers.get?.('content-type') ?? opts.headers['content-type']
     const mimeType = contentType ? parseMIMEType(contentType) : null
@@ -114,6 +123,10 @@ class FormDataParser extends Writable {
       this.#info.stream = null
     }
 
+    if (this.#info.headerEndSearch.lookedAt) {
+      this.emit('error', new Error('Malformed part header'))
+    }
+
     cb(err)
   }
 
@@ -178,76 +191,60 @@ class FormDataParser extends Writable {
         // arbitrary length. Therefore it's easier to read the headers, and
         // then parse once we receive 2 CRLFs which marks the body's start.
 
-        if (this.#byteOffset < 4) {
+        if (this.#byteOffset < crlfBuffer.length * 2) {
           return callback()
         }
 
-        // number of bytes to remove from the last buffer
-        let bytesToRemove = 0
-
-        done: { // eslint-disable-line no-labels
-          this.#info.headerState = headerStates.DEFAULT
-
-          for (let j = 0; j < this.#buffers.length; j++) {
-            const buffer = this.#buffers[j]
-
-            for (let i = 0; i < buffer.length; i++) {
-              const byte = buffer[i]
-              const state = this.#info.headerState
-
-              if (byte === chars.cr && state === headerStates.DEFAULT) {
-                this.#info.headerState = headerStates.FIRST
-              } else if (byte === chars.lf && state === headerStates.FIRST) {
-                this.#info.headerState = headerStates.SECOND
-              } else if (byte === chars.cr && state === headerStates.SECOND) {
-                this.#info.headerState = headerStates.THIRD
-              } else if (byte === chars.lf && state === headerStates.THIRD) {
-                // Got \r\n\r\n which marks the end of the headers.
-                this.#state = states.READ_BODY
-                bytesToRemove += i
-
-                const removed = this.consume(bytesToRemove - 3) // remove \r\n\r
-                const headers = this.#info.headers
-
-                // This is a very lazy implementation.
-                if ('content-type' in headers && headers['content-type'].length === 0) {
-                  const mimeUnparsed = removed.toString(this.#opts.defCharset)
-                  const mimeType = parseMIMEType(mimeUnparsed)
-
-                  if (mimeType !== 'failure') {
-                    headers['content-type'] = mimeType.essence
-                  }
-                }
-
-                this.#parseRawHeaders(removed)
-                this.consume(4)
-
-                break done // eslint-disable-line no-labels
-              } else {
-                this.#info.headerState = headerStates.DEFAULT
-
-                if (state === headerStates.SECOND) {
-                  const removed = this.consume(bytesToRemove + i - 2)
-
-                  if (this.#info.skipPart) {
-                    // If we are meant to skip this part, we shouldn't
-                    // parse the headers. We just need to consume the bytes.
-                    continue
-                  }
-
-                  this.#parseRawHeaders(removed)
-                  this.consume(2)
-                  bytesToRemove -= removed.length + 2
-                }
-              }
-            }
+        let i = this.#info.headerBuffersChecked
+
+        while (!this.#info.headerEndSearch.finished && i < this.#buffers.length) {
+          this.#info.headerEndSearch.write(this.#buffers[i++])
+          this.#info.headerBuffersChecked++
 
-            bytesToRemove += buffer.length
+          if (this.#info.headerEndSearch.lookedAt > maxHeaderLength) {
+            this.#info.skipPart = 'Malformed part header'
+            break
           }
+        }
 
+        if (!this.#info.headerEndSearch.finished) {
           return callback()
         }
 
+        const consumed = this.consume(this.#info.headerEndSearch.lookedAt)
+
+        this.#info.headerBuffersChecked = 0
+        this.#info.headerEndSearch.reset()
+
+        let index = consumed.indexOf(crlfBuffer)
+        let start = 0
+
+        while (index !== -1 && start < index) {
+          const buffer = consumed.subarray(start, index)
+          const valueIndex = buffer.indexOf(':')
+
+          if (valueIndex === -1) {
+            index = consumed.indexOf(crlfBuffer, index + buffer.length)
+            continue
+          } else if (!hasHeaderValue(buffer, valueIndex + 1)) {
+            // HTTP/1.1 header field values can be folded onto multiple lines if the
+            // continuation line begins with a space or horizontal tab.
+            index = consumed.indexOf(crlfBuffer, index + buffer.length)
+            continue
+          }
+
+          this.#parseRawHeaders(buffer)
+
+          start = index + 2
+          index = consumed.indexOf(crlfBuffer, start)
+
+          if (this.#info.skipPart) {
+            break
+          }
+        }
+
+        this.#state = states.READ_BODY
+
         const { attributes, ...headers } = this.#info.headers
 
         if (
@@ -257,6 +254,7 @@ class FormDataParser extends Writable {
             !attributes.name
           )
         ) {
+          this.#info.headers = { attributes: {} }
           // https://www.rfc-editor.org/rfc/rfc7578#section-4.2
           this.#info.skipPart = 'invalid content-disposition'
         } else if (
@@ -266,13 +264,18 @@ class FormDataParser extends Writable {
         ) {
           if (this.#info.limits.files >= this.#opts.limits.files) {
             this.#info.skipPart = 'file'
+            this.#info.headers = { attributes: {} }
             continue
           }
 
           // End the active stream if there is one
           this.#info.stream?.push(null)
-          this.#info.stream = new FileStream({ highWaterMark: this.#opts.fileHwm })
-          this.#info.stream.truncated = false // TODO
+          this.#info.stream = new FileStream({
+            highWaterMark: this.#opts.fileHwm,
+            autoDestroy: true,
+            emitClose: true
+          })
+          this.#info.stream.truncated = false
 
           this.emit(
             'file',
@@ -284,6 +287,7 @@ class FormDataParser extends Writable {
               mimeType: headers['content-type'] || 'application/octet-stream'
             }
           )
+          this.#info.headers = { attributes: {} }
         }
       } else if (this.#state === states.READ_BODY) {
         // A part's body can contain CRLFs so they cannot be used to
@@ -432,6 +436,7 @@ class FormDataParser extends Writable {
               }
             )
 
+            this.#info.headers = { attributes: {} }
             this.#info.limits.fields++
             body.chunks.length = 0
             body.length = 0
@@ -556,11 +561,15 @@ class FormDataParser extends Writable {
         continue
       }
 
-      if (buffer[position.position + 1] === chars[' ']) {
-        position.position += 2 // skip "; "
-      } else {
-        position.position++ // skip ":"
-      }
+      position.position++ // skip semicolon
+
+      // Header values can contain leading whitespace, make sure
+      // we remove it all.
+      collectASequenceOfCodePoints(
+        (char) => isWhitespace(char),
+        buffer,
+        position
+      )
 
       const value = collectASequenceOfCodePoints(
         (char) => {
diff --git a/lib/formdata/textsearch.js b/lib/formdata/textsearch.js
new file mode 100644
index 00000000000..bccc758ef44
--- /dev/null
+++ b/lib/formdata/textsearch.js
@@ -0,0 +1,47 @@
+'use strict'
+
+class TextSearch {
+  /** @param {Buffer} pattern */
+  constructor (pattern) {
+    this.pattern = pattern
+
+    this.back = 0
+    this.lookedAt = 0
+  }
+
+  /**
+   * @param {Buffer} chunk
+   */
+  write (chunk) {
+    if (this.finished) {
+      return true
+    }
+
+    for (const byte of chunk) {
+      this.lookedAt++
+
+      if (byte !== this.pattern[this.back]) {
+        this.back = 0
+      } else {
+        if (++this.back === this.pattern.length) {
+          return true
+        }
+      }
+    }
+
+    return this.back === this.pattern.length
+  }
+
+  reset () {
+    this.back = 0
+    this.lookedAt = 0
+  }
+
+  get finished () {
+    return this.back === this.pattern.length
+  }
+}
+
+module.exports = {
+  TextSearch
+}
diff --git a/lib/formdata/util.js b/lib/formdata/util.js
index 56edb482688..34bb6562970 100644
--- a/lib/formdata/util.js
+++ b/lib/formdata/util.js
@@ -33,7 +33,23 @@ function findCharacterType (type) {
   }
 }
 
+function isWhitespace (char) {
+  return char === 0x09 || char === 0x20 || char === 0x0D || char === 0x0A
+}
+
+function hasHeaderValue (chunk, start) {
+  for (let i = start; i < chunk.length; i++) {
+    if (!isWhitespace(chunk[i])) {
+      return true
+    }
+  }
+
+  return false
+}
+
 module.exports = {
   collectHTTPQuotedStringLenient,
-  findCharacterType
+  findCharacterType,
+  isWhitespace,
+  hasHeaderValue
 }
diff --git a/package.json b/package.json
index 37baa25665b..c32b0833e01 100644
--- a/package.json
+++ b/package.json
@@ -47,6 +47,7 @@
     "lint": "standard | snazzy",
     "lint:fix": "standard --fix | snazzy",
     "test": "npm run test:tap && npm run test:node-fetch && npm run test:fetch && npm run test:cookies && npm run test:wpt && npm run test:websocket && npm run test:jest && tsd",
+    "test:busboy": "node test/busboy/test.js",
     "test:cookies": "node scripts/verifyVersion 16 || tap test/cookie/*.js",
     "test:node-fetch": "node scripts/verifyVersion.js 16 || mocha test/node-fetch",
     "test:fetch": "node scripts/verifyVersion.js 16 || (npm run build:node && tap test/fetch/*.js && tap test/webidl/*.js)",
diff --git a/test/busboy/test-types-multipart.js b/test/busboy/test-types-multipart.js
index bf2edd65fd8..0e142963fb1 100644
--- a/test/busboy/test-types-multipart.js
+++ b/test/busboy/test-types-multipart.js
@@ -781,8 +781,6 @@ const tests = [
     what: 'Files limit'
   },
   {
-    // Note: this test is very slow because we need to write > 64 KiB
-    // of data one byte at a time.
     source: [
       ['-----------------------------paZqsnEHRufoShdX6fh0lUhXBP4k',
         'Content-Disposition: form-data; ' +

From 7b15177159e3d6aa7de0d1ca8961b140b4af631c Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Tue, 10 Jan 2023 23:08:08 -0500
Subject: [PATCH 31/36] fix: add main test file

---
 test/busboy/test.js | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 test/busboy/test.js

diff --git a/test/busboy/test.js b/test/busboy/test.js
new file mode 100644
index 00000000000..22c42d3fd6b
--- /dev/null
+++ b/test/busboy/test.js
@@ -0,0 +1,20 @@
+'use strict'
+
+const { spawnSync } = require('child_process')
+const { readdirSync } = require('fs')
+const { join } = require('path')
+
+const files = readdirSync(__dirname).sort()
+for (const filename of files) {
+  if (filename.startsWith('test-')) {
+    const path = join(__dirname, filename)
+    console.log(`> Running ${filename} ...`)
+    // Note: nyc changes process.argv0, process.execPath, etc.
+    const result = spawnSync(`node ${path}`, {
+      shell: true,
+      stdio: 'inherit',
+      windowsHide: true
+    })
+    if (result.status !== 0) { process.exitCode = 1 }
+  }
+}

From ac815206257f1cfdaa0c9954ca522a23a9940aad Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Tue, 10 Jan 2023 23:23:16 -0500
Subject: [PATCH 32/36] whoops, skip tests on < v18

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index c32b0833e01..bfe8bcb1dea 100644
--- a/package.json
+++ b/package.json
@@ -47,7 +47,7 @@
     "lint": "standard | snazzy",
     "lint:fix": "standard --fix | snazzy",
     "test": "npm run test:tap && npm run test:node-fetch && npm run test:fetch && npm run test:cookies && npm run test:wpt && npm run test:websocket && npm run test:jest && tsd",
-    "test:busboy": "node test/busboy/test.js",
+    "test:busboy": "node scripts/verifyVersion 18 || node test/busboy/test.js",
     "test:cookies": "node scripts/verifyVersion 16 || tap test/cookie/*.js",
     "test:node-fetch": "node scripts/verifyVersion.js 16 || mocha test/node-fetch",
     "test:fetch": "node scripts/verifyVersion.js 16 || (npm run build:node && tap test/fetch/*.js && tap test/webidl/*.js)",

From e9c8f93f76ebb9132d16505f479ea7f27410aa00 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Wed, 11 Jan 2023 11:14:13 -0500
Subject: [PATCH 33/36] apply suggestions

---
 lib/formdata/constants.js | 18 +++++++++---------
 lib/formdata/util.js      |  4 ++--
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/lib/formdata/constants.js b/lib/formdata/constants.js
index ef8d2a80a26..12ffbbc7942 100644
--- a/lib/formdata/constants.js
+++ b/lib/formdata/constants.js
@@ -15,19 +15,19 @@ const headerStates = {
 }
 
 const chars = {
-  '-': '-'.charCodeAt(0),
-  cr: '\r'.charCodeAt(0),
-  lf: '\n'.charCodeAt(0),
-  ':': ':'.charCodeAt(0),
-  ' ': ' '.charCodeAt(0), // 0x20
-  ';': ';'.charCodeAt(0),
-  '=': '='.charCodeAt(0),
-  '"': '"'.charCodeAt(0)
+  '-': 0x2D,
+  cr: 0x0D,
+  lf: 0x0A,
+  ':': 0x3A,
+  ' ': 0x20,
+  ';': 0x3B,
+  '=': 0x3D,
+  '"': 0x22
 }
 
 const emptyBuffer = Buffer.alloc(0)
 
-const crlfBuffer = Buffer.from('\r\n')
+const crlfBuffer = Buffer.from([0x0D, 0x0A]) // \r\n
 
 const maxHeaderLength = 16 * 1024
 
diff --git a/lib/formdata/util.js b/lib/formdata/util.js
index 34bb6562970..c9bfc469c9b 100644
--- a/lib/formdata/util.js
+++ b/lib/formdata/util.js
@@ -9,12 +9,12 @@ const { collectASequenceOfCodePoints } = require('../fetch/dataURL')
  * @param {string} str
  */
 function collectHTTPQuotedStringLenient (str) {
-  if (str[0] !== '"') {
+  if (!str.startsWith('"')) {
     return str
   }
 
   return collectASequenceOfCodePoints(
-    (char) => char !== '"',
+    (char) => char.charCodeAt(0) !== 0x22, // "
     str,
     { position: 1 }
   )

From 7642b605b17c2f3e8fc195ce7a872fc1051ab9c8 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Wed, 11 Jan 2023 13:54:20 -0500
Subject: [PATCH 34/36] cleanup FileStream

---
 lib/formdata/parser.js     | 3 +++
 test/client-request.js     | 2 +-
 test/fetch/client-fetch.js | 2 +-
 test/utils/formdata.js     | 4 ++--
 4 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index d4df1755d76..b34b5a22a51 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -270,6 +270,8 @@ class FormDataParser extends Writable {
 
           // End the active stream if there is one
           this.#info.stream?.push(null)
+          this.#info.stream?.destroy()
+
           this.#info.stream = new FileStream({
             highWaterMark: this.#opts.fileHwm,
             autoDestroy: true,
@@ -380,6 +382,7 @@ class FormDataParser extends Writable {
             this.#info.limits.fileSize += length
 
             this.#info.stream.push(limitedChunk)
+            this.#info.stream.push(null)
             this.#info.stream.destroy()
           } else if (
             this.#info.limits.fieldSize < this.#opts.limits.fieldSize &&
diff --git a/test/client-request.js b/test/client-request.js
index ff564604d42..fbb1265ca4e 100644
--- a/test/client-request.js
+++ b/test/client-request.js
@@ -658,7 +658,7 @@ test('request text2', (t) => {
   })
 })
 
-test('request with FormData body', { skip: nodeMajor < 16 }, (t) => {
+test('request with FormData body', { skip: nodeMajor < 18 }, (t) => {
   const { FormData } = require('../')
   const { Blob } = require('buffer')
 
diff --git a/test/fetch/client-fetch.js b/test/fetch/client-fetch.js
index 7a0cb550f54..fea06a2b392 100644
--- a/test/fetch/client-fetch.js
+++ b/test/fetch/client-fetch.js
@@ -247,7 +247,7 @@ test('multipart fromdata non-ascii filed names', async (t) => {
   t.equal(form.get('fiŝo'), 'value1')
 })
 
-test('busboy emit error', async (t) => {
+test('BodyMixin.formData rejects with mismatched boundary', async (t) => {
   t.plan(1)
   const formData = new FormData()
   formData.append('field1', 'value1')
diff --git a/test/utils/formdata.js b/test/utils/formdata.js
index 19dac3e84e5..24aee0a5c04 100644
--- a/test/utils/formdata.js
+++ b/test/utils/formdata.js
@@ -1,4 +1,4 @@
-const busboy = require('busboy')
+const { FormDataParser } = require('../..')
 
 function parseFormDataString (
   body,
@@ -9,7 +9,7 @@ function parseFormDataString (
     fields: []
   }
 
-  const bb = busboy({
+  const bb = new FormDataParser({
     headers: {
       'content-type': contentType
     }

From 588d62da9292be634b7402e0fde5d34341669860 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Wed, 11 Jan 2023 15:57:55 -0500
Subject: [PATCH 35/36] fix: replace busboy in fetch

---
 lib/fetch/body.js      | 22 +++++++++++-----------
 lib/formdata/parser.js |  2 ++
 package.json           |  4 +---
 3 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/lib/fetch/body.js b/lib/fetch/body.js
index c291afa9368..6ebf9b8723e 100644
--- a/lib/fetch/body.js
+++ b/lib/fetch/body.js
@@ -1,6 +1,5 @@
 'use strict'
 
-const Busboy = require('busboy')
 const util = require('../core/util')
 const {
   ReadableStreamFrom,
@@ -21,6 +20,7 @@ const { isErrored } = require('../core/util')
 const { isUint8Array, isArrayBuffer } = require('util/types')
 const { File: UndiciFile } = require('./file')
 const { parseMIMEType, serializeAMimeType } = require('./dataURL')
+const { FormDataParser } = require('../formdata/parser')
 
 let ReadableStream = globalThis.ReadableStream
 
@@ -374,10 +374,10 @@ function bodyMixinMethods (instance) {
 
         const responseFormData = new FormData()
 
-        let busboy
+        let parser
 
         try {
-          busboy = Busboy({
+          parser = new FormDataParser({
             headers,
             defParamCharset: 'utf8'
           })
@@ -385,10 +385,10 @@ function bodyMixinMethods (instance) {
           throw new DOMException(`${err}`, 'AbortError')
         }
 
-        busboy.on('field', (name, value) => {
+        parser.on('field', (name, value) => {
           responseFormData.append(name, value)
         })
-        busboy.on('file', (name, value, info) => {
+        parser.on('file', (name, value, info) => {
           const { filename, encoding, mimeType } = info
           const chunks = []
 
@@ -417,14 +417,14 @@ function bodyMixinMethods (instance) {
           }
         })
 
-        const busboyResolve = new Promise((resolve, reject) => {
-          busboy.on('finish', resolve)
-          busboy.on('error', (err) => reject(new TypeError(err)))
+        const promise = new Promise((resolve, reject) => {
+          parser.on('close', () => resolve())
+          parser.on('error', (err) => reject(new TypeError(err)))
         })
 
-        if (this.body !== null) for await (const chunk of consumeBody(this[kState].body)) busboy.write(chunk)
-        busboy.end()
-        await busboyResolve
+        if (this.body !== null) for await (const chunk of consumeBody(this[kState].body)) parser.write(chunk)
+        parser.end()
+        await promise
 
         return responseFormData
       } else if (/application\/x-www-form-urlencoded/.test(contentType)) {
diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index b34b5a22a51..910214f3a88 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -29,6 +29,7 @@ class FormDataParser extends Writable {
 
   #info = {
     headerState: headerStates.DEFAULT,
+    /** @type {FileStream|null} */
     stream: null,
     body: {
       chunks: [],
@@ -383,6 +384,7 @@ class FormDataParser extends Writable {
 
             this.#info.stream.push(limitedChunk)
             this.#info.stream.push(null)
+            this.#info.stream.read() // TODO: why is this needed!?!?!
             this.#info.stream.destroy()
           } else if (
             this.#info.limits.fieldSize < this.#opts.limits.fieldSize &&
diff --git a/package.json b/package.json
index bfe8bcb1dea..b74e71e7840 100644
--- a/package.json
+++ b/package.json
@@ -72,6 +72,7 @@
     "@types/node": "^18.0.3",
     "abort-controller": "^3.0.0",
     "atomic-sleep": "^1.0.0",
+    "busboy": "^1.6.0",
     "chai": "^4.3.4",
     "chai-as-promised": "^7.1.1",
     "chai-iterator": "^3.0.2",
@@ -130,8 +131,5 @@
     "testMatch": [
       "<rootDir>/test/jest/**"
     ]
-  },
-  "dependencies": {
-    "busboy": "^1.6.0"
   }
 }

From e21de0814ad3e8eb00a7e82570a0fba319893cb1 Mon Sep 17 00:00:00 2001
From: Khafra <42794878+KhafraDev@users.noreply.github.com>
Date: Sat, 25 Feb 2023 23:03:21 -0500
Subject: [PATCH 36/36] perf: use collectASequenceOfCodePointsFast

---
 lib/fetch/dataURL.js   |  4 +++-
 lib/formdata/parser.js | 13 +++++++------
 lib/formdata/util.js   |  6 +++---
 package.json           |  2 +-
 4 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/lib/fetch/dataURL.js b/lib/fetch/dataURL.js
index d287c5ad27e..f4e98592700 100644
--- a/lib/fetch/dataURL.js
+++ b/lib/fetch/dataURL.js
@@ -168,9 +168,11 @@ function collectASequenceOfCodePoints (condition, input, position) {
 
 /**
  * A faster collectASequenceOfCodePoints that only works when comparing a single character.
+ * @template {string|Buffer} T
  * @param {string} char
- * @param {string} input
+ * @param {T} input
  * @param {{ position: number }} position
+ * @returns {T}
  */
 function collectASequenceOfCodePointsFast (char, input, position) {
   const idx = input.indexOf(char, position.position)
diff --git a/lib/formdata/parser.js b/lib/formdata/parser.js
index 910214f3a88..19203f3a0ef 100644
--- a/lib/formdata/parser.js
+++ b/lib/formdata/parser.js
@@ -14,6 +14,7 @@ const { TextSearch } = require('./textsearch')
 const {
   parseMIMEType,
   collectASequenceOfCodePoints,
+  collectASequenceOfCodePointsFast,
   stringPercentDecode
 } = require('../fetch/dataURL')
 
@@ -519,8 +520,8 @@ class FormDataParser extends Writable {
     const position = { position: 0 }
 
     while (position.position < buffer.length) {
-      const nameBuffer = collectASequenceOfCodePoints(
-        (char) => char !== chars[':'],
+      const nameBuffer = collectASequenceOfCodePointsFast(
+        chars[':'],
         buffer,
         position
       )
@@ -557,8 +558,8 @@ class FormDataParser extends Writable {
 
         // Go to the next header if one is available. Headers are split by \r\n,
         // so we skip all characters until the sequence is found.
-        collectASequenceOfCodePoints(
-          (char) => char !== chars.cr && buffer[position.position + 1] !== chars.lf,
+        collectASequenceOfCodePointsFast(
+          '\r\n',
           buffer,
           position
         )
@@ -595,8 +596,8 @@ class FormDataParser extends Writable {
       }
 
       if (name !== 'content-disposition') {
-        collectASequenceOfCodePoints(
-          (char) => char !== chars.cr && buffer[position.position + 1] !== chars.lf,
+        collectASequenceOfCodePointsFast(
+          '\r\n',
           buffer,
           position
         )
diff --git a/lib/formdata/util.js b/lib/formdata/util.js
index c9bfc469c9b..e14d0ecae00 100644
--- a/lib/formdata/util.js
+++ b/lib/formdata/util.js
@@ -1,6 +1,6 @@
 'use strict'
 
-const { collectASequenceOfCodePoints } = require('../fetch/dataURL')
+const { collectASequenceOfCodePointsFast } = require('../fetch/dataURL')
 
 /**
  * Collect a string inside of quotes. Unlike
@@ -13,8 +13,8 @@ function collectHTTPQuotedStringLenient (str) {
     return str
   }
 
-  return collectASequenceOfCodePoints(
-    (char) => char.charCodeAt(0) !== 0x22, // "
+  return collectASequenceOfCodePointsFast(
+    '"',
     str,
     { position: 1 }
   )
diff --git a/package.json b/package.json
index b74e71e7840..4d667890de3 100644
--- a/package.json
+++ b/package.json
@@ -46,7 +46,7 @@
     "build:wasm": "node build/wasm.js --docker",
     "lint": "standard | snazzy",
     "lint:fix": "standard --fix | snazzy",
-    "test": "npm run test:tap && npm run test:node-fetch && npm run test:fetch && npm run test:cookies && npm run test:wpt && npm run test:websocket && npm run test:jest && tsd",
+    "test": "npm run test:tap && npm run test:node-fetch && npm run test:fetch && npm run test:cookies && npm run test:busboy && npm run test:wpt && npm run test:websocket && npm run test:jest && tsd",
     "test:busboy": "node scripts/verifyVersion 18 || node test/busboy/test.js",
     "test:cookies": "node scripts/verifyVersion 16 || tap test/cookie/*.js",
     "test:node-fetch": "node scripts/verifyVersion.js 16 || mocha test/node-fetch",