Merge pull request #35 from ony3000/fix-patching-process

Improves the process of applying patches

Author: ony3000

pnpm-lock.yaml

@@ -1,48 +1,84 @@
 import * as Diff from 'diff';
 
-enum PairingMode {
-  EVEN = 'even',
-  ODD = 'odd',
-}
-
-export type SubstitutePatch = {
-  from: string;
-  to: string;
-};
+export type SubstitutePatch =
+  | {
+      type: 'keep';
+      value: string;
+    }
+  | {
+      type: 'change';
+      from: string;
+      to: string;
+    };
 
 export function makePatches(oldStr: string, newStr: string): SubstitutePatch[] {
   if (oldStr === newStr) {
     return [];
   }
 
   const patches: SubstitutePatch[] = [];
-  let temporaryText = '';
-  let mode: PairingMode = PairingMode.EVEN;
-
-  Diff.diffLines(oldStr, newStr)
-    .filter((change) => 'added' in change && 'removed' in change)
-    .forEach((change) => {
-      if (!change.added && change.removed) {
-        if (mode === PairingMode.EVEN) {
-          temporaryText = change.value;
-          mode = PairingMode.ODD;
-        } else {
-          patches.push({ from: temporaryText, to: '' });
-          temporaryText = change.value;
-        }
-      } else if (change.added && !change.removed) {
-        if (mode === PairingMode.EVEN) {
-          patches.push({ from: '', to: change.value });
-        } else {
-          patches.push({ from: temporaryText, to: change.value });
-          mode = PairingMode.EVEN;
-        }
+  let temporaryText: string | null = null;
+
+  Diff.diffLines(oldStr, newStr).forEach((change) => {
+    if (change.added && change.removed) {
+      throw new Error('Unexpected change');
+    } else if (change.removed) {
+      if (temporaryText !== null) {
+        patches.push({ type: 'change', from: temporaryText, to: '' });
       }
-    });
+      temporaryText = change.value;
+    } else if (change.added) {
+      if (temporaryText === null) {
+        patches.push({ type: 'change', from: '', to: change.value });
+      } else {
+        patches.push({ type: 'change', from: temporaryText, to: change.value });
+        temporaryText = null;
+      }
+    } else {
+      if (temporaryText !== null) {
+        patches.push({ type: 'change', from: temporaryText, to: '' });
+        temporaryText = null;
+      }
+      patches.push({ type: 'keep', value: change.value });
+    }
+  });
 
   return patches;
 }
 
-export function applyPatches(text: string, patches: SubstitutePatch[]): string {
-  return patches.reduce((patchedPrevText, { from, to }) => patchedPrevText.replace(from, to), text);
+export function applyPatches(text: string, patchesPerPlugin: SubstitutePatch[][]): string {
+  return patchesPerPlugin.reduce((patchedPrevText, patches) => {
+    if (patches.length === 0) {
+      return patchedPrevText;
+    }
+
+    let mutablePrevText = patchedPrevText;
+    let scannedLength = 0;
+
+    patches.forEach((patch) => {
+      if (patch.type === 'keep') {
+        scannedLength += patch.value.length;
+      } else {
+        const prefix = mutablePrevText.slice(0, scannedLength);
+        const suffix = mutablePrevText.slice(scannedLength);
+
+        if (suffix.indexOf(patch.from) === -1) {
+          /**
+           * A correction value to skip other corresponding patches when a specific patch fails to be applied.
+           */
+          const skipLength = patch.from.length - patch.to.length;
+
+          scannedLength += patch.from.length + skipLength;
+        } else {
+          mutablePrevText = `${prefix}${suffix.replace(
+            patch.from,
+            patch.to.replace(/\$/g, '$$$$'),
+          )}`;
+          scannedLength += patch.to.length;
+        }
+      }
+    });
+
+    return mutablePrevText;
+  }, text);
 }

src/packages/core-parts/index.ts

@@ -56,9 +56,9 @@ function sequentialFormattingAndTryMerging(
       : format(originalText, sequentialFormattingOptions);
 
   /**
-   * Changes that may be removed during the sequential formatting process.
+   * List of output differences according to the presence or absence of each plugin.
    */
-  const patches: SubstitutePatch[] = [];
+  const patchesPerPlugin: SubstitutePatch[][] = [];
 
   const sequentiallyMergedText = plugins.reduce((formattedPrevText, plugin) => {
     const temporaryFormattedText =
@@ -77,13 +77,9 @@ function sequentialFormattingAndTryMerging(
         ? formatAsCodeblock(temporaryFormattedText, sequentialFormattingOptions)
         : format(temporaryFormattedText, sequentialFormattingOptions);
 
-    patches.push(...makePatches(temporaryFormattedTextWithoutPlugin, temporaryFormattedText));
+    patchesPerPlugin.push(makePatches(temporaryFormattedTextWithoutPlugin, temporaryFormattedText));
 
-    if (patches.length === 0) {
-      return temporaryFormattedText;
-    }
-
-    return applyPatches(temporaryFormattedTextWithoutPlugin, patches);
+    return applyPatches(temporaryFormattedTextWithoutPlugin, patchesPerPlugin);
   }, firstFormattedText);
 
   return sequentiallyMergedText;

src/packages/v2-plugin/parsers.ts

@@ -56,9 +56,9 @@ async function sequentialFormattingAndTryMerging(
       : format(originalText, sequentialFormattingOptions);
 
   /**
-   * Changes that may be removed during the sequential formatting process.
+   * List of output differences according to the presence or absence of each plugin.
    */
-  const patches: SubstitutePatch[] = [];
+  const patchesPerPlugin: SubstitutePatch[][] = [];
 
   const sequentiallyMergedText = await plugins.reduce<Promise<string>>(
     async (formattedPrevTextPromise, plugin) => {
@@ -80,13 +80,11 @@ async function sequentialFormattingAndTryMerging(
           ? await formatAsCodeblock(temporaryFormattedText, sequentialFormattingOptions)
           : await format(temporaryFormattedText, sequentialFormattingOptions);
 
-      patches.push(...makePatches(temporaryFormattedTextWithoutPlugin, temporaryFormattedText));
-
-      if (patches.length === 0) {
-        return temporaryFormattedText;
-      }
+      patchesPerPlugin.push(
+        makePatches(temporaryFormattedTextWithoutPlugin, temporaryFormattedText),
+      );
 
-      return applyPatches(temporaryFormattedTextWithoutPlugin, patches);
+      return applyPatches(temporaryFormattedTextWithoutPlugin, patchesPerPlugin);
     },
     firstFormattedTextPromise,
   );

src/packages/v3-plugin/parsers.ts

@@ -420,6 +420,40 @@ export function Callout({ children }) {
       endOfLine: 'crlf',
     },
   },
+  {
+    name: 'issue #34 (1) - standalone use',
+    input: `
+export function $1_$$2_$$$3_$$$$4({ children }) {
+  return <div>{children}</div>;
+}
+`,
+    output: `export function $1_$$2_$$$3_$$$$4({ children })
+{
+  return <div>{children}</div>;
+}
+`,
+    options: {
+      plugins: ['prettier-plugin-brace-style'],
+      ...braceStylePluginOptions,
+    },
+  },
+  {
+    name: 'issue #34 (2) - a combination of a single plugin and a merge plugin also has no effect',
+    input: `
+export function $1_$$2_$$$3_$$$$4({ children }) {
+  return <div>{children}</div>;
+}
+`,
+    output: `export function $1_$$2_$$$3_$$$$4({ children })
+{
+  return <div>{children}</div>;
+}
+`,
+    options: {
+      plugins: ['prettier-plugin-brace-style', thisPlugin],
+      ...braceStylePluginOptions,
+    },
+  },
 ];
 
 testEach(fixtures, options);

tests/v2-test/babel/single-plugin.test.ts

@@ -420,6 +420,40 @@ export function Callout({ children }) {
       endOfLine: 'crlf',
     },
   },
+  {
+    name: 'issue #34 (1) - standalone use',
+    input: `
+export function $1_$$2_$$$3_$$$$4({ children }) {
+  return <div>{children}</div>;
+}
+`,
+    output: `export function $1_$$2_$$$3_$$$$4({ children })
+{
+  return <div>{children}</div>;
+}
+`,
+    options: {
+      plugins: ['prettier-plugin-brace-style'],
+      ...braceStylePluginOptions,
+    },
+  },
+  {
+    name: 'issue #34 (2) - a combination of a single plugin and a merge plugin also has no effect',
+    input: `
+export function $1_$$2_$$$3_$$$$4({ children }) {
+  return <div>{children}</div>;
+}
+`,
+    output: `export function $1_$$2_$$$3_$$$$4({ children })
+{
+  return <div>{children}</div>;
+}
+`,
+    options: {
+      plugins: ['prettier-plugin-brace-style', thisPlugin],
+      ...braceStylePluginOptions,
+    },
+  },
 ];
 
 testEach(fixtures, options);