fix(replace-node): compare children only when the node.kind is not of type Identifier

Author: tusharmath

src/eq-node.ts

@@ -1,21 +1,36 @@
 import * as ts from 'typescript'
-
+const debug = require('debug')('ts-codemod:eq')
 export function eqNode(a: ts.Node, b: ts.Node): boolean {
-  return (
-    strictlyEq(a, b) || eqIdentifier(a, b) || (eqKind(a, b) && eqChildren(a, b))
-  )
+  return strictlyEq(a, b) || eqIdentifier(a, b) || eqChildren(a, b)
 }
 
 function eqChildren(a: ts.Node, b: ts.Node): boolean {
-  return a.getChildren().every((aChild, id) => eqNode(b.getChildAt(id), aChild))
+  /**
+   * Children comparison should happen only for nodes that are
+   * not of type Identifier
+   */
+  if (eqKind(a, b) && !ts.isIdentifier(a)) {
+    const result = a
+      .getChildren()
+      .every((aChild, id) => eqNode(b.getChildAt(id), aChild))
+    if (result)
+      debug('children:', `'${a.getFullText()}'`, `'${b.getFullText()}'`)
+    return result
+  }
+  return false
 }
 
 function eqKind(a: ts.Node, b: ts.Node) {
-  return a.kind === b.kind
+  const result = a.kind === b.kind
+  if (result) debug('kind:', `'${a.getFullText()}'`, `'${b.getFullText()}'`)
+  if (result) return result
 }
 
 function eqIdentifier(a: ts.Node, b: ts.Node): boolean {
-  return ts.isIdentifier(a) && ts.isIdentifier(b) && a.text === b.text
+  const result = ts.isIdentifier(a) && ts.isIdentifier(b) && a.text === b.text
+  if (result)
+    debug('identifier:', `'${a.getFullText()}'`, `'${b.getFullText()}'`)
+  return result
 }
 
 function strictlyEq(a: ts.Node, b: ts.Node) {

test/replace-node.test.ts

@@ -23,4 +23,23 @@ describe('replace-node', () => {
     }).newContent
     assert.strictEqual(actual, expected)
   })
+
+  it('should convert identifiers', () => {
+    const input = normalize(`
+      import {Hoe} from '@action-land/core'
+      export const view = (e: Hoe, m: {}, p: {}) => 'Hello'
+    `)
+    const expected = normalize(`
+    import {Smitten} from '@action-land/core'
+    export const view = (e: Smitten, m: {}, p: {}) => 'Hello'
+    `)
+
+    const actual = transform({
+      transformationCtor: ReplaceNode,
+      content: input,
+      path: './src/file.ts',
+      params: {matchWith: 'Hoe', replaceWith: 'Smitten'}
+    }).newContent
+    assert.strictEqual(actual, expected)
+  })
 })

transformations/replace-node.ts

@@ -1,5 +1,8 @@
 import {Transformation} from '..'
 import * as ts from 'typescript'
+const debug = require('debug')('ts-codemod:replace-node')
+
+const cName = (obj: any) => obj.constructor.name.replace('Object', '')
 
 export default class ReplaceNode extends Transformation<{
   matchWith: string
@@ -9,11 +12,24 @@ export default class ReplaceNode extends Transformation<{
   private replaceWith: ts.Node = ts.createEmptyStatement()
 
   init() {
-    this.matchWith = this.toNode(this.params.matchWith)
-    this.replaceWith = this.toNode(this.params.replaceWith)
+    const {matchWith, replaceWith} = this.params
+    this.matchWith = this.toNode(matchWith)
+    this.replaceWith = this.toNode(replaceWith)
+    debug('matchWith:', cName(this.matchWith), `'${matchWith}'`)
+    debug('replaceWith:', cName(this.replaceWith), `'${replaceWith}'`)
   }
 
   visit(node: ts.Node): ts.VisitResult<ts.Node> {
-    return this.equal(node, this.matchWith) ? this.replaceWith : node
+    debug('node:', cName(node), `'${node.getFullText()}'`)
+    if (this.equal(node, this.matchWith)) {
+      debug(
+        'replacing',
+        node.getFullText(),
+        'with',
+        this.replaceWith.getFullText()
+      )
+      return this.replaceWith
+    }
+    return node
   }
 }