test: add benchmark with vitest + codspeed

.github/workflows/bench.yml

@@ -0,0 +1,26 @@
+name: benchmark
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+  workflow_dispatch:
+
+jobs:
+  run:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: pnpm/action-setup@v2
+      - uses: actions/setup-node@v3
+        with:
+          cache: pnpm
+      - name: Install dependencies
+        run: pnpm install
+      - name: Run benchmarks
+        uses: CodSpeedHQ/action@v2
+        with:
+          run: pnpm vitest bench
+          # token retrieved from the CodSpeed app at the previous step
+          token: ${{ secrets.CODSPEED_TOKEN }}

package.json

@@ -58,6 +58,7 @@
     "unplugin": "^1.8.3"
   },
   "devDependencies": {
+    "@codspeed/vitest-plugin": "^3.1.0",
     "@antfu/eslint-config": "2.8.0",
     "@nuxt/kit": "3.10.3",
     "@types/estree": "1.0.5",

test/transform.bench.ts

@@ -0,0 +1,66 @@
+import { bench, describe } from 'vitest'
+import { parse } from 'acorn'
+
+import { MagicRegExpTransformPlugin } from '../src/transform'
+
+describe(`transformer: magic-regexp`, () => {
+  const couldTransform = [
+    `import { createRegExp, exactly, anyOf } from 'magic-regexp'`,
+    "const re1 = createRegExp(exactly('bar').notBefore('foo'))",
+  ]
+
+  bench('ignores non-JS files', () => {
+    transform(couldTransform, 'test.css')
+  })
+
+  bench('transforms vue script blocks', () => {
+    transform(couldTransform, 'test.vue?type=script')
+    transform(couldTransform, 'test.vue')
+    transform(couldTransform, 'test.vue?type=template')
+  })
+
+  bench(`ignores code without imports from magic-regexp`, () => {
+    transform(couldTransform[1])
+    transform([`// magic-regexp`, couldTransform[1]])
+  })
+
+  bench('preserves context for dynamic regexps', () => {
+    transform([
+      `import { createRegExp } from 'magic-regexp'`,
+      `console.log(createRegExp(anyOf(keys)))`,
+    ])
+  })
+
+  bench('statically replaces regexps where possible', () => {
+    transform([
+      "import { something } from 'other-module'",
+      `import { createRegExp, exactly, anyOf } from 'magic-regexp'`,
+      '//', // this lets us tree-shake the import for use in our test-suite
+      "const re1 = createRegExp(exactly('bar').notBefore('foo'))",
+      "const re2 = createRegExp(anyOf(exactly('bar'), 'foo'))",
+      "const re3 = createRegExp('/foo/bar')",
+      // This line will be double-escaped in the snapshot
+      "re3.test('/foo/bar')",
+    ])
+  })
+
+  bench('respects how users import library', () => {
+    transform([
+      `import { createRegExp as cRE } from 'magic-regexp'`,
+      `import { exactly as ext, createRegExp } from 'magic-regexp'`,
+      `import * as magicRE from 'magic-regexp'`,
+      "const re1 = cRE(ext('bar').notBefore('foo'))",
+      "const re2 = magicRE.createRegExp(magicRE.anyOf('bar', 'foo'))",
+      "const re3 = createRegExp('test/value')",
+    ])
+  })
+})
+
+const transform = (code: string | string[], id = 'some-id.js') => {
+  const plugin = MagicRegExpTransformPlugin.vite() as any
+  return plugin.transform.call(
+    { parse: (code: string) => parse(code, { ecmaVersion: 2022, sourceType: 'module' }) },
+    Array.isArray(code) ? code.join('\n') : code,
+    id
+  )?.code
+}

vitest.config.ts → vitest.config.mts

@@ -1,7 +1,9 @@
 import { fileURLToPath } from 'node:url'
+import codspeedPlugin from '@codspeed/vitest-plugin'
 import { defineConfig } from 'vitest/config'
 
 export default defineConfig({
+  plugins: [codspeedPlugin()],
   resolve: {
     alias: {
       'magic-regexp': fileURLToPath(new URL('./src/index.ts', import.meta.url).href),