From 779f779f8fadae87d15ae6bbe76dbe94be56009e Mon Sep 17 00:00:00 2001
From: yuzheng14 <422450117@qq.com>
Date: Wed, 10 Jul 2024 10:25:15 +0800
Subject: [PATCH 1/6] fix(build): handle invalid JSON in import.meta.env

---
 .../src/node/__tests__/plugins/define.spec.ts | 14 +++++++++++++
 packages/vite/src/node/plugins/define.ts      |  5 +++--
 playground/define/__tests__/define.spec.ts    | 13 ++++++++++++
 playground/define/index.html                  | 21 +++++++++++++++++++
 playground/define/vite.config.js              |  1 +
 5 files changed, 52 insertions(+), 2 deletions(-)

diff --git a/packages/vite/src/node/__tests__/plugins/define.spec.ts b/packages/vite/src/node/__tests__/plugins/define.spec.ts
index 8876a9d7ecc3e2..8969b3ef038ff3 100644
--- a/packages/vite/src/node/__tests__/plugins/define.spec.ts
+++ b/packages/vite/src/node/__tests__/plugins/define.spec.ts
@@ -72,4 +72,18 @@ describe('definePlugin', () => {
       'const foo = import.meta.env.UNKNOWN;\n',
     )
   })
+
+  test('replace import.meta.env when it is a invalid json', async () => {
+    const transform = await createDefinePluginTransform({
+      'import.meta.env.LEGACY': '__VITE_IS_LEGACY__',
+    })
+
+    expect(
+      await transform(
+        'const isLegacy = import.meta.env.LEGACY;\nimport.meta.env.UNDEFINED && console.log(import.meta.env.UNDEFINED);',
+      ),
+    ).toBe(
+      'var define_import_meta_env_default = {"BASE_URL": "/", "MODE": "development", "DEV": true, "PROD": false, "SSR": false, "LEGACY": __VITE_IS_LEGACY__};\nconst isLegacy = __VITE_IS_LEGACY__;\ndefine_import_meta_env_default.UNDEFINED && console.log(define_import_meta_env_default.UNDEFINED);\n',
+    )
+  })
 })
diff --git a/packages/vite/src/node/plugins/define.ts b/packages/vite/src/node/plugins/define.ts
index 786a1038505c00..d3085c38cbc8b1 100644
--- a/packages/vite/src/node/plugins/define.ts
+++ b/packages/vite/src/node/plugins/define.ts
@@ -142,8 +142,9 @@ export async function replaceDefine(
   const replacementMarkers: Record<string, string> = {}
   const env = define['import.meta.env']
   if (env && !canJsonParse(env)) {
-    const marker = `_${getHash(env, env.length - 2)}_`
-    replacementMarkers[marker] = env
+    const marker = `{ "_${getHash(env, env.length - 2)}_": "" }`
+    // result generated by esbuild will not have the quotes around the keys
+    replacementMarkers[marker.replace('"', '').replace('"', '')] = env
     define = { ...define, 'import.meta.env': marker }
   }
 
diff --git a/playground/define/__tests__/define.spec.ts b/playground/define/__tests__/define.spec.ts
index ec1801c7876ca4..574839137c4c7a 100644
--- a/playground/define/__tests__/define.spec.ts
+++ b/playground/define/__tests__/define.spec.ts
@@ -92,3 +92,16 @@ test('replaces constants in template literal expressions', async () => {
     ),
   ).toBe('dev')
 })
+
+test('replace constants on import.meta.env when it is a invalid json', async () => {
+  expect(
+    await page.textContent(
+      '.replace-undefined-constants-on-import-meta-env .import-meta-env-UNDEFINED',
+    ),
+  ).toBe('undefined')
+  expect(
+    await page.textContent(
+      '.replace-undefined-constants-on-import-meta-env .import-meta-env-LEGACY',
+    ),
+  ).toBe('true')
+})
diff --git a/playground/define/index.html b/playground/define/index.html
index 2c2898771e5d4e..747859da29cf94 100644
--- a/playground/define/index.html
+++ b/playground/define/index.html
@@ -60,6 +60,18 @@ <h2>Define replaces constants in template literal expressions</h2>
   <p>import.meta.hot <code class="import-meta-hot"></code></p>
 </section>
 
+<h2>Define undefined constants on import.meta.env when it's a invalid json</h2>
+<section class="replace-undefined-constants-on-import-meta-env">
+  <p>
+    import.meta.env.UNDEFINED <code class="import-meta-env-UNDEFINED"></code>
+  </p>
+  <p>import.meta.env.LEGACY <code class="import-meta-env-LEGACY"></code></p>
+</section>
+
+<script>
+  // simulate legacy mode
+  window.__VITE_IS_LEGACY__ = true
+</script>
 <script type="module">
   const __VAR_NAME__ = true // ensure define doesn't replace var name
   text('.exp', typeof __EXP__) // typeof __EXP__ would be `boolean` instead of `string`
@@ -127,6 +139,15 @@ <h2>Define replaces constants in template literal expressions</h2>
     '.replaces-constants-in-template-literal-expressions .process-env-NODE_ENV',
     `${process.env.NODE_ENV}`,
   )
+
+  text(
+    '.replace-undefined-constants-on-import-meta-env .import-meta-env-UNDEFINED',
+    `${import.meta.env.UNDEFINED}`,
+  )
+  text(
+    '.replace-undefined-constants-on-import-meta-env .import-meta-env-LEGACY',
+    `${import.meta.env.LEGACY}`,
+  )
 </script>
 
 <style>
diff --git a/playground/define/vite.config.js b/playground/define/vite.config.js
index 997f2b9ae83931..4e5c1662adb742 100644
--- a/playground/define/vite.config.js
+++ b/playground/define/vite.config.js
@@ -29,5 +29,6 @@ export default defineConfig({
     ÖUNICODE_LETTERɵ: 789,
     __VAR_NAME__: false,
     __STRINGIFIED_OBJ__: JSON.stringify({ foo: true }),
+    'import.meta.env.LEGACY': '__VITE_IS_LEGACY__',
   },
 })

From d7eb09b2c595952e3031fa43bb6c724327b41a2f Mon Sep 17 00:00:00 2001
From: yuzheng14 <422450117@qq.com>
Date: Wed, 24 Jul 2024 15:01:33 +0800
Subject: [PATCH 2/6] refactor(build): change a strategy to handle
 `import.meta.env` and undefined key

---
 .../src/node/__tests__/plugins/define.spec.ts | 17 ++++-
 packages/vite/src/node/plugins/define.ts      | 76 ++++++++++---------
 2 files changed, 54 insertions(+), 39 deletions(-)

diff --git a/packages/vite/src/node/__tests__/plugins/define.spec.ts b/packages/vite/src/node/__tests__/plugins/define.spec.ts
index 8969b3ef038ff3..29fa5251c3597f 100644
--- a/packages/vite/src/node/__tests__/plugins/define.spec.ts
+++ b/packages/vite/src/node/__tests__/plugins/define.spec.ts
@@ -82,8 +82,19 @@ describe('definePlugin', () => {
       await transform(
         'const isLegacy = import.meta.env.LEGACY;\nimport.meta.env.UNDEFINED && console.log(import.meta.env.UNDEFINED);',
       ),
-    ).toBe(
-      'var define_import_meta_env_default = {"BASE_URL": "/", "MODE": "development", "DEV": true, "PROD": false, "SSR": false, "LEGACY": __VITE_IS_LEGACY__};\nconst isLegacy = __VITE_IS_LEGACY__;\ndefine_import_meta_env_default.UNDEFINED && console.log(define_import_meta_env_default.UNDEFINED);\n',
-    )
+    ).toMatchInlineSnapshot(`
+      "const isLegacy = __VITE_IS_LEGACY__;
+      "
+    `)
+  })
+
+  test('replace bare import.meta.env', async () => {
+    const transform = await createDefinePluginTransform()
+    expect(await transform('const env = import.meta.env;'))
+      .toMatchInlineSnapshot(`
+      "const __vite_import_meta_env__ = {"BASE_URL": "/", "MODE": "development", "DEV": true, "PROD": false, "SSR": false};
+      const env = __vite_import_meta_env__;
+      "
+    `)
   })
 })
diff --git a/packages/vite/src/node/plugins/define.ts b/packages/vite/src/node/plugins/define.ts
index d3085c38cbc8b1..d553e669f16e97 100644
--- a/packages/vite/src/node/plugins/define.ts
+++ b/packages/vite/src/node/plugins/define.ts
@@ -2,12 +2,14 @@ import { transform } from 'esbuild'
 import { TraceMap, decodedMap, encodedMap } from '@jridgewell/trace-mapping'
 import type { ResolvedConfig } from '../config'
 import type { Plugin } from '../plugin'
-import { escapeRegex, getHash } from '../utils'
+import { escapeRegex } from '../utils'
 import { isCSSRequest } from './css'
 import { isHTMLRequest } from './html'
 
 const nonJsRe = /\.json(?:$|\?)/
 const isNonJsRequest = (request: string): boolean => nonJsRe.test(request)
+const importMetaEnvMarker = '__vite_import_meta_env__'
+const bareImportMetaEnvRe = /import\.meta\.env(?!\.)\b/
 
 export function definePlugin(config: ResolvedConfig): Plugin {
   const isBuild = config.command === 'build'
@@ -69,13 +71,24 @@ export function definePlugin(config: ResolvedConfig): Plugin {
       define['import.meta.env.SSR'] = ssr + ''
     }
     if ('import.meta.env' in define) {
-      define['import.meta.env'] = serializeDefine({
-        ...importMetaEnvKeys,
-        SSR: ssr + '',
-        ...userDefineEnv,
-      })
+      define['import.meta.env'] = importMetaEnvMarker
     }
 
+    const importMetaEnv = {
+      ...importMetaEnvKeys,
+      SSR: ssr + '',
+      ...userDefineEnv,
+    }
+    const importMetaEnvVal = serializeDefine(importMetaEnv)
+    // replace bare `import.meta.env` manually
+    const banner = `const ${importMetaEnvMarker} = ${importMetaEnvVal};`
+    // create regex pattern to match undefined `import.meta.env` properties
+    // to replace it to `undefined` directly
+    const undefinedPattern = new RegExp(
+      `import\\.meta\\.env\\.(?!${Object.keys(importMetaEnv).map(escapeRegex).join('|')}).+?\\b`,
+      'g',
+    )
+
     // Create regex pattern as a fast check before running esbuild
     const patternKeys = Object.keys(userDefine)
     if (replaceProcessEnv && Object.keys(processEnv).length) {
@@ -88,7 +101,7 @@ export function definePlugin(config: ResolvedConfig): Plugin {
       ? new RegExp(patternKeys.map(escapeRegex).join('|'))
       : null
 
-    return [define, pattern] as const
+    return [define, pattern, undefinedPattern, banner] as const
   }
 
   const defaultPattern = generatePattern(false)
@@ -116,14 +129,30 @@ export function definePlugin(config: ResolvedConfig): Plugin {
         return
       }
 
-      const [define, pattern] = ssr ? ssrPattern : defaultPattern
+      const [define, pattern, undefinedPattern, banner] = ssr
+        ? ssrPattern
+        : defaultPattern
       if (!pattern) return
 
       // Check if our code needs any replacements before running esbuild
       pattern.lastIndex = 0
       if (!pattern.test(code)) return
 
-      return await replaceDefine(code, id, define, config)
+      // process undefined imports.meta.env properties
+      const defineWithUndefined = { ...define }
+      undefinedPattern.lastIndex = 0
+      for (const undefinedEnvKey of [...code.matchAll(undefinedPattern)]) {
+        defineWithUndefined[undefinedEnvKey[0]] = 'undefined'
+      }
+
+      return await replaceDefine(
+        code,
+        id,
+        defineWithUndefined,
+        config,
+        // if there is bare `import.meta.env`, then add the manual `import.meta.env`
+        bareImportMetaEnvRe.test(code) ? banner : undefined,
+      )
     },
   }
 }
@@ -133,21 +162,8 @@ export async function replaceDefine(
   id: string,
   define: Record<string, string>,
   config: ResolvedConfig,
+  banner?: string,
 ): Promise<{ code: string; map: string | null }> {
-  // Because esbuild only allows JSON-serializable values, and `import.meta.env`
-  // may contain values with raw identifiers, making it non-JSON-serializable,
-  // we replace it with a temporary marker and then replace it back after to
-  // workaround it. This means that esbuild is unable to optimize the `import.meta.env`
-  // access, but that's a tradeoff for now.
-  const replacementMarkers: Record<string, string> = {}
-  const env = define['import.meta.env']
-  if (env && !canJsonParse(env)) {
-    const marker = `{ "_${getHash(env, env.length - 2)}_": "" }`
-    // result generated by esbuild will not have the quotes around the keys
-    replacementMarkers[marker.replace('"', '').replace('"', '')] = env
-    define = { ...define, 'import.meta.env': marker }
-  }
-
   const esbuildOptions = config.esbuild || {}
 
   const result = await transform(code, {
@@ -157,6 +173,7 @@ export async function replaceDefine(
     define,
     sourcefile: id,
     sourcemap: config.command === 'build' ? !!config.build.sourcemap : true,
+    banner,
   })
 
   // remove esbuild's <define:...> source entries
@@ -179,10 +196,6 @@ export async function replaceDefine(
     }
   }
 
-  for (const marker in replacementMarkers) {
-    result.code = result.code.replaceAll(marker, replacementMarkers[marker])
-  }
-
   return {
     code: result.code,
     map: result.map || null,
@@ -213,12 +226,3 @@ function handleDefineValue(value: any): string {
   if (typeof value === 'string') return value
   return JSON.stringify(value)
 }
-
-function canJsonParse(value: any): boolean {
-  try {
-    JSON.parse(value)
-    return true
-  } catch {
-    return false
-  }
-}

From 8a1081496e1f763b94954b02855140c702f506c4 Mon Sep 17 00:00:00 2001
From: yuzheng14 <422450117@qq.com>
Date: Wed, 24 Jul 2024 16:11:39 +0800
Subject: [PATCH 3/6] test(define): renew test case to pass through CI

---
 packages/vite/src/node/__tests__/plugins/define.spec.ts | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/packages/vite/src/node/__tests__/plugins/define.spec.ts b/packages/vite/src/node/__tests__/plugins/define.spec.ts
index 29fa5251c3597f..05f5d69d582f67 100644
--- a/packages/vite/src/node/__tests__/plugins/define.spec.ts
+++ b/packages/vite/src/node/__tests__/plugins/define.spec.ts
@@ -90,11 +90,8 @@ describe('definePlugin', () => {
 
   test('replace bare import.meta.env', async () => {
     const transform = await createDefinePluginTransform()
-    expect(await transform('const env = import.meta.env;'))
-      .toMatchInlineSnapshot(`
-      "const __vite_import_meta_env__ = {"BASE_URL": "/", "MODE": "development", "DEV": true, "PROD": false, "SSR": false};
-      const env = __vite_import_meta_env__;
-      "
-    `)
+    expect(await transform('const env = import.meta.env;')).toMatch(
+      /const __vite_import_meta_env__ = .*;\nconst env = __vite_import_meta_env__;/,
+    )
   })
 })

From 04267532ea5b163f3f04b9db3032de7e8a730fd3 Mon Sep 17 00:00:00 2001
From: yuzheng14 <422450117@qq.com>
Date: Thu, 25 Jul 2024 13:21:16 +0800
Subject: [PATCH 4/6] refactor(build): replace manual `import.meta.env` after
 `replaceDefine`

---
 .../src/node/__tests__/plugins/define.spec.ts |  1 +
 packages/vite/src/node/plugins/define.ts      | 73 ++++++++++---------
 playground/define/__tests__/define.spec.ts    |  2 +-
 playground/define/index.html                  | 13 ++--
 playground/define/vite.config.js              |  2 +-
 5 files changed, 51 insertions(+), 40 deletions(-)

diff --git a/packages/vite/src/node/__tests__/plugins/define.spec.ts b/packages/vite/src/node/__tests__/plugins/define.spec.ts
index 05f5d69d582f67..eda3da60485736 100644
--- a/packages/vite/src/node/__tests__/plugins/define.spec.ts
+++ b/packages/vite/src/node/__tests__/plugins/define.spec.ts
@@ -84,6 +84,7 @@ describe('definePlugin', () => {
       ),
     ).toMatchInlineSnapshot(`
       "const isLegacy = __VITE_IS_LEGACY__;
+      undefined && console.log(undefined);
       "
     `)
   })
diff --git a/packages/vite/src/node/plugins/define.ts b/packages/vite/src/node/plugins/define.ts
index d553e669f16e97..c2c24a2961835c 100644
--- a/packages/vite/src/node/plugins/define.ts
+++ b/packages/vite/src/node/plugins/define.ts
@@ -1,15 +1,18 @@
 import { transform } from 'esbuild'
 import { TraceMap, decodedMap, encodedMap } from '@jridgewell/trace-mapping'
+import MagicString from 'magic-string'
+import type { SourceMap } from 'rollup'
 import type { ResolvedConfig } from '../config'
 import type { Plugin } from '../plugin'
-import { escapeRegex } from '../utils'
+import { combineSourcemaps, escapeRegex } from '../utils'
 import { isCSSRequest } from './css'
 import { isHTMLRequest } from './html'
 
 const nonJsRe = /\.json(?:$|\?)/
 const isNonJsRequest = (request: string): boolean => nonJsRe.test(request)
 const importMetaEnvMarker = '__vite_import_meta_env__'
-const bareImportMetaEnvRe = /import\.meta\.env(?!\.)\b/
+const bareImportMetaEnvRe = new RegExp(`${importMetaEnvMarker}(?!\\.)\\b`)
+const importMetaEnvKeyRe = new RegExp(`${importMetaEnvMarker}\\..+?\\b`, 'g')
 
 export function definePlugin(config: ResolvedConfig): Plugin {
   const isBuild = config.command === 'build'
@@ -74,20 +77,12 @@ export function definePlugin(config: ResolvedConfig): Plugin {
       define['import.meta.env'] = importMetaEnvMarker
     }
 
-    const importMetaEnv = {
+    const importMetaEnvVal = serializeDefine({
       ...importMetaEnvKeys,
       SSR: ssr + '',
       ...userDefineEnv,
-    }
-    const importMetaEnvVal = serializeDefine(importMetaEnv)
-    // replace bare `import.meta.env` manually
-    const banner = `const ${importMetaEnvMarker} = ${importMetaEnvVal};`
-    // create regex pattern to match undefined `import.meta.env` properties
-    // to replace it to `undefined` directly
-    const undefinedPattern = new RegExp(
-      `import\\.meta\\.env\\.(?!${Object.keys(importMetaEnv).map(escapeRegex).join('|')}).+?\\b`,
-      'g',
-    )
+    })
+    const banner = `const ${importMetaEnvMarker} = ${importMetaEnvVal};\n`
 
     // Create regex pattern as a fast check before running esbuild
     const patternKeys = Object.keys(userDefine)
@@ -101,7 +96,7 @@ export function definePlugin(config: ResolvedConfig): Plugin {
       ? new RegExp(patternKeys.map(escapeRegex).join('|'))
       : null
 
-    return [define, pattern, undefinedPattern, banner] as const
+    return [define, pattern, banner] as const
   }
 
   const defaultPattern = generatePattern(false)
@@ -129,30 +124,44 @@ export function definePlugin(config: ResolvedConfig): Plugin {
         return
       }
 
-      const [define, pattern, undefinedPattern, banner] = ssr
-        ? ssrPattern
-        : defaultPattern
+      const [define, pattern, banner] = ssr ? ssrPattern : defaultPattern
       if (!pattern) return
 
       // Check if our code needs any replacements before running esbuild
       pattern.lastIndex = 0
       if (!pattern.test(code)) return
 
-      // process undefined imports.meta.env properties
-      const defineWithUndefined = { ...define }
-      undefinedPattern.lastIndex = 0
-      for (const undefinedEnvKey of [...code.matchAll(undefinedPattern)]) {
-        defineWithUndefined[undefinedEnvKey[0]] = 'undefined'
+      const esbuildResult = await replaceDefine(code, id, define, config)
+
+      // replace undefined `import.meta.env` keys
+      // and bare `import.meta.env` references
+      bareImportMetaEnvRe.lastIndex = 0
+      importMetaEnvKeyRe.lastIndex = 0
+      if (esbuildResult.map) {
+        const ms = new MagicString(esbuildResult.code)
+        ms.replaceAll(importMetaEnvKeyRe, 'undefined')
+        let finalCode = ms.toString()
+        if (bareImportMetaEnvRe.test(finalCode)) {
+          ms.prepend(banner)
+          finalCode = ms.toString()
+        }
+        return {
+          code: finalCode,
+          map: combineSourcemaps(id, [
+            JSON.parse(esbuildResult.map),
+            ms.generateMap({ hires: 'boundary' }),
+          ]) as SourceMap,
+        }
+      } else {
+        esbuildResult.code = esbuildResult.code.replaceAll(
+          importMetaEnvKeyRe,
+          'undefined',
+        )
+        if (bareImportMetaEnvRe.test(esbuildResult.code)) {
+          esbuildResult.code = banner + esbuildResult.code
+        }
+        return esbuildResult
       }
-
-      return await replaceDefine(
-        code,
-        id,
-        defineWithUndefined,
-        config,
-        // if there is bare `import.meta.env`, then add the manual `import.meta.env`
-        bareImportMetaEnvRe.test(code) ? banner : undefined,
-      )
     },
   }
 }
@@ -162,7 +171,6 @@ export async function replaceDefine(
   id: string,
   define: Record<string, string>,
   config: ResolvedConfig,
-  banner?: string,
 ): Promise<{ code: string; map: string | null }> {
   const esbuildOptions = config.esbuild || {}
 
@@ -173,7 +181,6 @@ export async function replaceDefine(
     define,
     sourcefile: id,
     sourcemap: config.command === 'build' ? !!config.build.sourcemap : true,
-    banner,
   })
 
   // remove esbuild's <define:...> source entries
diff --git a/playground/define/__tests__/define.spec.ts b/playground/define/__tests__/define.spec.ts
index 574839137c4c7a..399e9c801266a9 100644
--- a/playground/define/__tests__/define.spec.ts
+++ b/playground/define/__tests__/define.spec.ts
@@ -101,7 +101,7 @@ test('replace constants on import.meta.env when it is a invalid json', async ()
   ).toBe('undefined')
   expect(
     await page.textContent(
-      '.replace-undefined-constants-on-import-meta-env .import-meta-env-LEGACY',
+      '.replace-undefined-constants-on-import-meta-env .import-meta-env-SOME_IDENTIFIER',
     ),
   ).toBe('true')
 })
diff --git a/playground/define/index.html b/playground/define/index.html
index 747859da29cf94..164ba46c64bd0e 100644
--- a/playground/define/index.html
+++ b/playground/define/index.html
@@ -65,12 +65,15 @@ <h2>Define undefined constants on import.meta.env when it's a invalid json</h2>
   <p>
     import.meta.env.UNDEFINED <code class="import-meta-env-UNDEFINED"></code>
   </p>
-  <p>import.meta.env.LEGACY <code class="import-meta-env-LEGACY"></code></p>
+  <p>
+    import.meta.env.SOME_IDENTIFIER
+    <code class="import-meta-env-SOME_IDENTIFIER"></code>
+  </p>
 </section>
 
 <script>
-  // simulate legacy mode
-  window.__VITE_IS_LEGACY__ = true
+  // inject __VITE_SOME_IDENTIFIER__ to test if it's replaced
+  window.__VITE_SOME_IDENTIFIER__ = true
 </script>
 <script type="module">
   const __VAR_NAME__ = true // ensure define doesn't replace var name
@@ -145,8 +148,8 @@ <h2>Define undefined constants on import.meta.env when it's a invalid json</h2>
     `${import.meta.env.UNDEFINED}`,
   )
   text(
-    '.replace-undefined-constants-on-import-meta-env .import-meta-env-LEGACY',
-    `${import.meta.env.LEGACY}`,
+    '.replace-undefined-constants-on-import-meta-env .import-meta-env-SOME_IDENTIFIER',
+    `${import.meta.env.SOME_IDENTIFIER}`,
   )
 </script>
 
diff --git a/playground/define/vite.config.js b/playground/define/vite.config.js
index 4e5c1662adb742..d6c4d22709266b 100644
--- a/playground/define/vite.config.js
+++ b/playground/define/vite.config.js
@@ -29,6 +29,6 @@ export default defineConfig({
     ÖUNICODE_LETTERɵ: 789,
     __VAR_NAME__: false,
     __STRINGIFIED_OBJ__: JSON.stringify({ foo: true }),
-    'import.meta.env.LEGACY': '__VITE_IS_LEGACY__',
+    'import.meta.env.SOME_IDENTIFIER': '__VITE_SOME_IDENTIFIER__',
   },
 })

From 891fd0e2a314e9f93dbf1b458029c5feed1f3712 Mon Sep 17 00:00:00 2001
From: bluwy <bjornlu.dev@gmail.com>
Date: Thu, 25 Jul 2024 16:17:27 +0800
Subject: [PATCH 5/6] refactor: improve sourcemap perf

---
 .../src/node/__tests__/plugins/define.spec.ts | 14 ++++++
 packages/vite/src/node/plugins/define.ts      | 50 +++++++------------
 2 files changed, 32 insertions(+), 32 deletions(-)

diff --git a/packages/vite/src/node/__tests__/plugins/define.spec.ts b/packages/vite/src/node/__tests__/plugins/define.spec.ts
index eda3da60485736..eaf7a6095fc59f 100644
--- a/packages/vite/src/node/__tests__/plugins/define.spec.ts
+++ b/packages/vite/src/node/__tests__/plugins/define.spec.ts
@@ -64,6 +64,20 @@ describe('definePlugin', () => {
     )
   })
 
+  test('replace import.meta.env.UNKNOWN with undefined', async () => {
+    const transform = await createDefinePluginTransform()
+    expect(await transform('const foo = import.meta.env.UNKNOWN;')).toBe(
+      'const foo = undefined                       ;\n',
+    )
+  })
+
+  test('leave import.meta.env["UNKNOWN"] to runtime', async () => {
+    const transform = await createDefinePluginTransform()
+    expect(await transform('const foo = import.meta.env["UNKNOWN"];')).toMatch(
+      /const __vite_import_meta_env__ = .*;\nconst foo = __vite_import_meta_env__\["UNKNOWN"\];/,
+    )
+  })
+
   test('preserve import.meta.env.UNKNOWN with override', async () => {
     const transform = await createDefinePluginTransform({
       'import.meta.env.UNKNOWN': 'import.meta.env.UNKNOWN',
diff --git a/packages/vite/src/node/plugins/define.ts b/packages/vite/src/node/plugins/define.ts
index c2c24a2961835c..b59f452083f56c 100644
--- a/packages/vite/src/node/plugins/define.ts
+++ b/packages/vite/src/node/plugins/define.ts
@@ -1,10 +1,8 @@
 import { transform } from 'esbuild'
 import { TraceMap, decodedMap, encodedMap } from '@jridgewell/trace-mapping'
-import MagicString from 'magic-string'
-import type { SourceMap } from 'rollup'
 import type { ResolvedConfig } from '../config'
 import type { Plugin } from '../plugin'
-import { combineSourcemaps, escapeRegex } from '../utils'
+import { escapeRegex } from '../utils'
 import { isCSSRequest } from './css'
 import { isHTMLRequest } from './html'
 
@@ -131,37 +129,25 @@ export function definePlugin(config: ResolvedConfig): Plugin {
       pattern.lastIndex = 0
       if (!pattern.test(code)) return
 
-      const esbuildResult = await replaceDefine(code, id, define, config)
-
-      // replace undefined `import.meta.env` keys
-      // and bare `import.meta.env` references
-      bareImportMetaEnvRe.lastIndex = 0
-      importMetaEnvKeyRe.lastIndex = 0
-      if (esbuildResult.map) {
-        const ms = new MagicString(esbuildResult.code)
-        ms.replaceAll(importMetaEnvKeyRe, 'undefined')
-        let finalCode = ms.toString()
-        if (bareImportMetaEnvRe.test(finalCode)) {
-          ms.prepend(banner)
-          finalCode = ms.toString()
-        }
-        return {
-          code: finalCode,
-          map: combineSourcemaps(id, [
-            JSON.parse(esbuildResult.map),
-            ms.generateMap({ hires: 'boundary' }),
-          ]) as SourceMap,
-        }
-      } else {
-        esbuildResult.code = esbuildResult.code.replaceAll(
-          importMetaEnvKeyRe,
-          'undefined',
-        )
-        if (bareImportMetaEnvRe.test(esbuildResult.code)) {
-          esbuildResult.code = banner + esbuildResult.code
+      const result = await replaceDefine(code, id, define, config)
+
+      // Replace `import.meta.env.*` with undefined
+      result.code = result.code.replaceAll(importMetaEnvKeyRe, (m) =>
+        'undefined'.padEnd(m.length),
+      )
+
+      // If there's bare `import.meta.env` references, prepend the banner
+      if (bareImportMetaEnvRe.test(result.code)) {
+        result.code = banner + result.code
+
+        if (result.map) {
+          const map = JSON.parse(result.map)
+          map.mappings = ';' + map.mappings
+          result.map = map
         }
-        return esbuildResult
       }
+
+      return result
     },
   }
 }

From c8e9034c0fde4fa902924d99bb0242b3a1656ab7 Mon Sep 17 00:00:00 2001
From: bluwy <bjornlu.dev@gmail.com>
Date: Thu, 25 Jul 2024 16:19:59 +0800
Subject: [PATCH 6/6] chore: update snapshots

---
 packages/vite/src/node/__tests__/plugins/define.spec.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/vite/src/node/__tests__/plugins/define.spec.ts b/packages/vite/src/node/__tests__/plugins/define.spec.ts
index eaf7a6095fc59f..2165461c77acaa 100644
--- a/packages/vite/src/node/__tests__/plugins/define.spec.ts
+++ b/packages/vite/src/node/__tests__/plugins/define.spec.ts
@@ -98,7 +98,7 @@ describe('definePlugin', () => {
       ),
     ).toMatchInlineSnapshot(`
       "const isLegacy = __VITE_IS_LEGACY__;
-      undefined && console.log(undefined);
+      undefined                          && console.log(undefined                         );
       "
     `)
   })