feat(route-del-to-delete): add migration codemod for app.del() to app.delete() (#102)

* feat(route-del-to-delete): add migration codemod for app.del() to app.delete()

* fix(workflow): simplify early return checks for nodes and edits

* fix(codemod): update repository URL in codemod.yaml

* fix(docs): clarify deprecation of app.del() in migration guide

Author: bjohansebas

codemods/route-del-to-delete/README.md

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+# Migrate legacy `app.del()` to `app.delete()`
+
+Migrates usage of the legacy APIs `app.del()` to `app.delete()`.
+Initially, `del` was used instead of `delete`, because `delete` is a reserved keyword in JavaScript. However, as of ECMAScript 6, `delete` and other reserved keywords can legally be used as property names. The `app.del()` method was deprecated in Express 4 and removed in Express 5. 
+
+## Example
+
+### Migrating `app.del()`
+
+The migration involves replacing instances of `app.del()` with `app.delete()`.
+
+```diff
+- app.del('/some-route', (req, res) => {
++ app.delete('/some-route', (req, res) => {
+    // Some logic here
+ });
+```
+
+## References
+
+- [Migration of app.del()](https://expressjs.com/en/guide/migrating-5.html#app.del)

codemods/route-del-to-delete/codemod.yaml

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+schema_version: "1.0"
+name: "@expressjs/route-del-to-delete"
+version: "1.0.0"
+description: Migrates usage of the legacy APIs `app.del()` to `app.delete()`
+author: bjohansebas (Sebastian Beltran)
+license: MIT
+workflow: workflow.yaml
+repository: "https://github.com/expressjs/codemod/tree/HEAD/codemods/route-del-to-delete"
+category: migration
+
+targets:
+  languages:
+    - javascript
+    - typescript
+
+keywords:
+  - transformation
+  - migration
+  - express
+  - redirect
+  - location
+
+registry:
+  access: public
+  visibility: public

codemods/route-del-to-delete/package.json

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+{
+  "name": "@expressjs/route-del-to-delete",
+  "private": true,
+  "version": "1.0.0",
+  "description": "Migrates usage of the legacy APIs `app.del` to `app.delete`.",
+  "type": "module",
+  "scripts": {
+    "test": "npx codemod jssg test -l typescript ./src/workflow.ts ./"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/expressjs/codemod.git",
+    "directory": "codemods/route-del-to-delete",
+    "bugs": "https://github.com/expressjs/codemod/issues"
+  },
+  "author": "bjohansebas (Sebastian Beltran)",
+  "license": "MIT",
+  "homepage": "https://github.com/expressjs/codemod/blob/main/codemods/route-del-to-delete/README.md",
+  "devDependencies": {
+    "@codemod.com/jssg-types": "^1.3.1"
+  }
+}

codemods/route-del-to-delete/src/workflow.ts

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+import type Js from '@codemod.com/jssg-types/src/langs/javascript'
+import type { Edit, SgRoot } from '@codemod.com/jssg-types/src/main'
+
+async function transform(root: SgRoot<Js>): Promise<string | null> {
+  const rootNode = root.root()
+
+  const nodes = rootNode.findAll({
+    rule: {
+      pattern: '$OBJ.$METHOD($$$ARG)',
+    },
+    constraints: {
+      METHOD: { regex: '^(del)$' },
+    },
+  })
+
+  if (!nodes.length) return null
+
+  const edits: Edit[] = []
+
+  for (const call of nodes) {
+    const method = call.getMatch('METHOD')
+    const args = call.getMultipleMatches('ARG')
+    if (!method) continue
+
+    // $$$ARG yields argument nodes interleaved with separators, so arg nodes are at 0,2,4...
+    const first = args[0]
+    if (!first) continue
+
+    const isString = first.is('string')
+    const isRegexp = first.is('regexp') || first.is('regex') || first.is('regular_expression')
+    const isArray = first.is('array') || first.is('array_expression')
+
+    if (!isString && !isRegexp && !isArray) continue
+
+    edits.push(method.replace('delete'))
+  }
+
+  if (!edits.length) return null
+
+  return rootNode.commitEdits(edits)
+}
+
+export default transform

codemods/route-del-to-delete/tests/expected/delete.ts

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+import express from "express";
+
+const app = express();
+
+app.get("/", (req, res) => {});
+
+app.delete([""],() => {
+  myImportantLogic();
+});
+
+app.delete([],() => {
+  myImportantLogic();
+});
+
+app.delete(/d/,() => {
+  myImportantLogic();
+});
+
+app.del(() => {
+  myImportantLogic();
+});
+
+app.del(function () {
+  myImportantLogic();
+});
+
+app.delete("/old", () => {
+  myImportantLogic();
+});
+
+function noModify() {
+  let a
+
+  app.del(a)
+}
+
+const myImportantLogic = () => {
+  console.log("making sure it's there");
+};

codemods/route-del-to-delete/tests/input/delete.ts

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+import express from "express";
+
+const app = express();
+
+app.get("/", (req, res) => {});
+
+app.del([""],() => {
+  myImportantLogic();
+});
+
+app.del([],() => {
+  myImportantLogic();
+});
+
+app.del(/d/,() => {
+  myImportantLogic();
+});
+
+app.del(() => {
+  myImportantLogic();
+});
+
+app.del(function () {
+  myImportantLogic();
+});
+
+app.del("/old", () => {
+  myImportantLogic();
+});
+
+function noModify() {
+  let a
+
+  app.del(a)
+}
+
+const myImportantLogic = () => {
+  console.log("making sure it's there");
+};

codemods/route-del-to-delete/workflow.yaml

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+# yaml-language-server: $schema=https://raw.githubusercontent.com/codemod-com/codemod/refs/heads/main/schemas/workflow.json
+
+version: "1"
+
+nodes:
+  - id: apply-transforms
+    name: Apply AST Transformations
+    type: automatic
+    runtime:
+      type: direct
+    steps:
+      - name: Migrates usage of the legacy APIs `app.del()` to `app.delete()`
+        js-ast-grep:
+          js_file: src/workflow.ts
+          base_path: .
+          semantic_analysis: file
+          include:
+            - "**/*.cjs"
+            - "**/*.js"
+            - "**/*.jsx"
+            - "**/*.mjs"
+            - "**/*.cts"
+            - "**/*.mts"
+            - "**/*.ts"
+            - "**/*.tsx"
+          exclude:
+            - "**/node_modules/**"
+          language: typescript