perf: avoid sourcemap chains during dev (#8796)

Co-authored-by: yoho <panyoho@gmail.com>
vitejs · Jun 26, 2022 · 1566f61 · 1566f61
1 parent 8bb452d
commit 1566f61
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Showing 12 changed files with 378 additions and 505 deletions.
diff --git a/packages/vite/src/node/__tests__/plugins/importGlob/__snapshots__/fixture.test.ts.snap b/packages/vite/src/node/__tests__/plugins/importGlob/__snapshots__/fixture.test.ts.snap
@@ -1,164 +1,44 @@
 // Vitest Snapshot v1
 
 exports[`fixture > transform 1`] = `
-"import * as __vite_glob_1_0 from \\"./modules/a.ts\\"
-import * as __vite_glob_1_1 from \\"./modules/b.ts\\"
-import * as __vite_glob_1_2 from \\"./modules/index.ts\\"
-import { name as __vite_glob_3_0 } from \\"./modules/a.ts\\"
-import { name as __vite_glob_3_1 } from \\"./modules/b.ts\\"
-import { name as __vite_glob_3_2 } from \\"./modules/index.ts\\"
-import { default as __vite_glob_5_0 } from \\"./modules/a.ts?raw\\"
-import { default as __vite_glob_5_1 } from \\"./modules/b.ts?raw\\"
-import \\"../../../../../../types/importMeta\\";
-export const basic = Object.assign({
-\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\"),
-\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\"),
-\\"./modules/index.ts\\": () => import(\\"./modules/index.ts\\")
-});
-export const basicEager = Object.assign({
-\\"./modules/a.ts\\": __vite_glob_1_0,
-\\"./modules/b.ts\\": __vite_glob_1_1,
-\\"./modules/index.ts\\": __vite_glob_1_2
-});
-export const ignore = Object.assign({
-\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\"),
-\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\")
-});
-export const namedEager = Object.assign({
-\\"./modules/a.ts\\": __vite_glob_3_0,
-\\"./modules/b.ts\\": __vite_glob_3_1,
-\\"./modules/index.ts\\": __vite_glob_3_2
-});
-export const namedDefault = Object.assign({
-\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\").then(m => m[\\"default\\"]),
-\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\").then(m => m[\\"default\\"]),
-\\"./modules/index.ts\\": () => import(\\"./modules/index.ts\\").then(m => m[\\"default\\"])
-});
-export const eagerAs = Object.assign({
-\\"./modules/a.ts\\": __vite_glob_5_0,
-\\"./modules/b.ts\\": __vite_glob_5_1
-});
-export const rawImportModule = Object.assign({
-\\"./modules/a.ts\\": () => import(\\"./modules/a.ts?raw\\"),
-\\"./modules/b.ts\\": () => import(\\"./modules/b.ts?raw\\")
-});
-export const excludeSelf = Object.assign({
-\\"./sibling.ts\\": () => import(\\"./sibling.ts\\")
-});
-export const customQueryString = Object.assign({
-\\"./sibling.ts\\": () => import(\\"./sibling.ts?custom\\")
-});
-export const customQueryObject = Object.assign({
-\\"./sibling.ts\\": () => import(\\"./sibling.ts?foo=bar&raw=true\\")
-});
-export const parent = Object.assign({
-
-});
-export const rootMixedRelative = Object.assign({
-\\"/css.spec.ts\\": () => import(\\"../../css.spec.ts?url\\").then(m => m[\\"default\\"]),
-\\"/define.spec.ts\\": () => import(\\"../../define.spec.ts?url\\").then(m => m[\\"default\\"]),
-\\"/esbuild.spec.ts\\": () => import(\\"../../esbuild.spec.ts?url\\").then(m => m[\\"default\\"]),
-\\"/import.spec.ts\\": () => import(\\"../../import.spec.ts?url\\").then(m => m[\\"default\\"]),
-\\"/importGlob/fixture-b/a.ts\\": () => import(\\"../fixture-b/a.ts?url\\").then(m => m[\\"default\\"]),
-\\"/importGlob/fixture-b/b.ts\\": () => import(\\"../fixture-b/b.ts?url\\").then(m => m[\\"default\\"]),
-\\"/importGlob/fixture-b/index.ts\\": () => import(\\"../fixture-b/index.ts?url\\").then(m => m[\\"default\\"])
-});
-export const cleverCwd1 = Object.assign({
-\\"./node_modules/framework/pages/hello.page.js\\": () => import(\\"./node_modules/framework/pages/hello.page.js\\")
-});
-export const cleverCwd2 = Object.assign({
-\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\"),
-\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\"),
-\\"../fixture-b/a.ts\\": () => import(\\"../fixture-b/a.ts\\"),
-\\"../fixture-b/b.ts\\": () => import(\\"../fixture-b/b.ts\\")
-});
+"import * as __vite_glob_1_0 from \\"./modules/a.ts\\";import * as __vite_glob_1_1 from \\"./modules/b.ts\\";import * as __vite_glob_1_2 from \\"./modules/index.ts\\";import { name as __vite_glob_3_0 } from \\"./modules/a.ts\\";import { name as __vite_glob_3_1 } from \\"./modules/b.ts\\";import { name as __vite_glob_3_2 } from \\"./modules/index.ts\\";import { default as __vite_glob_5_0 } from \\"./modules/a.ts?raw\\";import { default as __vite_glob_5_1 } from \\"./modules/b.ts?raw\\";import \\"../../../../../../types/importMeta\\";
+export const basic = Object.assign({\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\"),\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\"),\\"./modules/index.ts\\": () => import(\\"./modules/index.ts\\")});
+export const basicEager = Object.assign({\\"./modules/a.ts\\": __vite_glob_1_0,\\"./modules/b.ts\\": __vite_glob_1_1,\\"./modules/index.ts\\": __vite_glob_1_2});
+export const ignore = Object.assign({\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\"),\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\")});
+export const namedEager = Object.assign({\\"./modules/a.ts\\": __vite_glob_3_0,\\"./modules/b.ts\\": __vite_glob_3_1,\\"./modules/index.ts\\": __vite_glob_3_2});
+export const namedDefault = Object.assign({\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\").then(m => m[\\"default\\"]),\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\").then(m => m[\\"default\\"]),\\"./modules/index.ts\\": () => import(\\"./modules/index.ts\\").then(m => m[\\"default\\"])});
+export const eagerAs = Object.assign({\\"./modules/a.ts\\": __vite_glob_5_0,\\"./modules/b.ts\\": __vite_glob_5_1});
+export const rawImportModule = Object.assign({\\"./modules/a.ts\\": () => import(\\"./modules/a.ts?raw\\"),\\"./modules/b.ts\\": () => import(\\"./modules/b.ts?raw\\")});
+export const excludeSelf = Object.assign({\\"./sibling.ts\\": () => import(\\"./sibling.ts\\")});
+export const customQueryString = Object.assign({\\"./sibling.ts\\": () => import(\\"./sibling.ts?custom\\")});
+export const customQueryObject = Object.assign({\\"./sibling.ts\\": () => import(\\"./sibling.ts?foo=bar&raw=true\\")});
+export const parent = Object.assign({});
+export const rootMixedRelative = Object.assign({\\"/css.spec.ts\\": () => import(\\"../../css.spec.ts?url\\").then(m => m[\\"default\\"]),\\"/define.spec.ts\\": () => import(\\"../../define.spec.ts?url\\").then(m => m[\\"default\\"]),\\"/esbuild.spec.ts\\": () => import(\\"../../esbuild.spec.ts?url\\").then(m => m[\\"default\\"]),\\"/import.spec.ts\\": () => import(\\"../../import.spec.ts?url\\").then(m => m[\\"default\\"]),\\"/importGlob/fixture-b/a.ts\\": () => import(\\"../fixture-b/a.ts?url\\").then(m => m[\\"default\\"]),\\"/importGlob/fixture-b/b.ts\\": () => import(\\"../fixture-b/b.ts?url\\").then(m => m[\\"default\\"]),\\"/importGlob/fixture-b/index.ts\\": () => import(\\"../fixture-b/index.ts?url\\").then(m => m[\\"default\\"])});
+export const cleverCwd1 = Object.assign({\\"./node_modules/framework/pages/hello.page.js\\": () => import(\\"./node_modules/framework/pages/hello.page.js\\")});
+export const cleverCwd2 = Object.assign({\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\"),\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\"),\\"../fixture-b/a.ts\\": () => import(\\"../fixture-b/a.ts\\"),\\"../fixture-b/b.ts\\": () => import(\\"../fixture-b/b.ts\\")});
 "
 `;
 
 exports[`fixture > transform with restoreQueryExtension 1`] = `
-"import * as __vite_glob_1_0 from \\"./modules/a.ts\\"
-import * as __vite_glob_1_1 from \\"./modules/b.ts\\"
-import * as __vite_glob_1_2 from \\"./modules/index.ts\\"
-import { name as __vite_glob_3_0 } from \\"./modules/a.ts\\"
-import { name as __vite_glob_3_1 } from \\"./modules/b.ts\\"
-import { name as __vite_glob_3_2 } from \\"./modules/index.ts\\"
-import { default as __vite_glob_5_0 } from \\"./modules/a.ts?raw\\"
-import { default as __vite_glob_5_1 } from \\"./modules/b.ts?raw\\"
-import \\"../../../../../../types/importMeta\\";
-export const basic = Object.assign({
-\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\"),
-\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\"),
-\\"./modules/index.ts\\": () => import(\\"./modules/index.ts\\")
-});
-export const basicEager = Object.assign({
-\\"./modules/a.ts\\": __vite_glob_1_0,
-\\"./modules/b.ts\\": __vite_glob_1_1,
-\\"./modules/index.ts\\": __vite_glob_1_2
-});
-export const ignore = Object.assign({
-\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\"),
-\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\")
-});
-export const namedEager = Object.assign({
-\\"./modules/a.ts\\": __vite_glob_3_0,
-\\"./modules/b.ts\\": __vite_glob_3_1,
-\\"./modules/index.ts\\": __vite_glob_3_2
-});
-export const namedDefault = Object.assign({
-\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\").then(m => m[\\"default\\"]),
-\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\").then(m => m[\\"default\\"]),
-\\"./modules/index.ts\\": () => import(\\"./modules/index.ts\\").then(m => m[\\"default\\"])
-});
-export const eagerAs = Object.assign({
-\\"./modules/a.ts\\": __vite_glob_5_0,
-\\"./modules/b.ts\\": __vite_glob_5_1
-});
-export const rawImportModule = Object.assign({
-\\"./modules/a.ts\\": () => import(\\"./modules/a.ts?raw\\"),
-\\"./modules/b.ts\\": () => import(\\"./modules/b.ts?raw\\")
-});
-export const excludeSelf = Object.assign({
-\\"./sibling.ts\\": () => import(\\"./sibling.ts\\")
-});
-export const customQueryString = Object.assign({
-\\"./sibling.ts\\": () => import(\\"./sibling.ts?custom&lang.ts\\")
-});
-export const customQueryObject = Object.assign({
-\\"./sibling.ts\\": () => import(\\"./sibling.ts?foo=bar&raw=true&lang.ts\\")
-});
-export const parent = Object.assign({
-
-});
-export const rootMixedRelative = Object.assign({
-\\"/css.spec.ts\\": () => import(\\"../../css.spec.ts?url&lang.ts\\").then(m => m[\\"default\\"]),
-\\"/define.spec.ts\\": () => import(\\"../../define.spec.ts?url&lang.ts\\").then(m => m[\\"default\\"]),
-\\"/esbuild.spec.ts\\": () => import(\\"../../esbuild.spec.ts?url&lang.ts\\").then(m => m[\\"default\\"]),
-\\"/import.spec.ts\\": () => import(\\"../../import.spec.ts?url&lang.ts\\").then(m => m[\\"default\\"]),
-\\"/importGlob/fixture-b/a.ts\\": () => import(\\"../fixture-b/a.ts?url&lang.ts\\").then(m => m[\\"default\\"]),
-\\"/importGlob/fixture-b/b.ts\\": () => import(\\"../fixture-b/b.ts?url&lang.ts\\").then(m => m[\\"default\\"]),
-\\"/importGlob/fixture-b/index.ts\\": () => import(\\"../fixture-b/index.ts?url&lang.ts\\").then(m => m[\\"default\\"])
-});
-export const cleverCwd1 = Object.assign({
-\\"./node_modules/framework/pages/hello.page.js\\": () => import(\\"./node_modules/framework/pages/hello.page.js\\")
-});
-export const cleverCwd2 = Object.assign({
-\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\"),
-\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\"),
-\\"../fixture-b/a.ts\\": () => import(\\"../fixture-b/a.ts\\"),
-\\"../fixture-b/b.ts\\": () => import(\\"../fixture-b/b.ts\\")
-});
+"import * as __vite_glob_1_0 from \\"./modules/a.ts\\";import * as __vite_glob_1_1 from \\"./modules/b.ts\\";import * as __vite_glob_1_2 from \\"./modules/index.ts\\";import { name as __vite_glob_3_0 } from \\"./modules/a.ts\\";import { name as __vite_glob_3_1 } from \\"./modules/b.ts\\";import { name as __vite_glob_3_2 } from \\"./modules/index.ts\\";import { default as __vite_glob_5_0 } from \\"./modules/a.ts?raw\\";import { default as __vite_glob_5_1 } from \\"./modules/b.ts?raw\\";import \\"../../../../../../types/importMeta\\";
+export const basic = Object.assign({\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\"),\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\"),\\"./modules/index.ts\\": () => import(\\"./modules/index.ts\\")});
+export const basicEager = Object.assign({\\"./modules/a.ts\\": __vite_glob_1_0,\\"./modules/b.ts\\": __vite_glob_1_1,\\"./modules/index.ts\\": __vite_glob_1_2});
+export const ignore = Object.assign({\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\"),\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\")});
+export const namedEager = Object.assign({\\"./modules/a.ts\\": __vite_glob_3_0,\\"./modules/b.ts\\": __vite_glob_3_1,\\"./modules/index.ts\\": __vite_glob_3_2});
+export const namedDefault = Object.assign({\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\").then(m => m[\\"default\\"]),\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\").then(m => m[\\"default\\"]),\\"./modules/index.ts\\": () => import(\\"./modules/index.ts\\").then(m => m[\\"default\\"])});
+export const eagerAs = Object.assign({\\"./modules/a.ts\\": __vite_glob_5_0,\\"./modules/b.ts\\": __vite_glob_5_1});
+export const rawImportModule = Object.assign({\\"./modules/a.ts\\": () => import(\\"./modules/a.ts?raw\\"),\\"./modules/b.ts\\": () => import(\\"./modules/b.ts?raw\\")});
+export const excludeSelf = Object.assign({\\"./sibling.ts\\": () => import(\\"./sibling.ts\\")});
+export const customQueryString = Object.assign({\\"./sibling.ts\\": () => import(\\"./sibling.ts?custom&lang.ts\\")});
+export const customQueryObject = Object.assign({\\"./sibling.ts\\": () => import(\\"./sibling.ts?foo=bar&raw=true&lang.ts\\")});
+export const parent = Object.assign({});
+export const rootMixedRelative = Object.assign({\\"/css.spec.ts\\": () => import(\\"../../css.spec.ts?url&lang.ts\\").then(m => m[\\"default\\"]),\\"/define.spec.ts\\": () => import(\\"../../define.spec.ts?url&lang.ts\\").then(m => m[\\"default\\"]),\\"/esbuild.spec.ts\\": () => import(\\"../../esbuild.spec.ts?url&lang.ts\\").then(m => m[\\"default\\"]),\\"/import.spec.ts\\": () => import(\\"../../import.spec.ts?url&lang.ts\\").then(m => m[\\"default\\"]),\\"/importGlob/fixture-b/a.ts\\": () => import(\\"../fixture-b/a.ts?url&lang.ts\\").then(m => m[\\"default\\"]),\\"/importGlob/fixture-b/b.ts\\": () => import(\\"../fixture-b/b.ts?url&lang.ts\\").then(m => m[\\"default\\"]),\\"/importGlob/fixture-b/index.ts\\": () => import(\\"../fixture-b/index.ts?url&lang.ts\\").then(m => m[\\"default\\"])});
+export const cleverCwd1 = Object.assign({\\"./node_modules/framework/pages/hello.page.js\\": () => import(\\"./node_modules/framework/pages/hello.page.js\\")});
+export const cleverCwd2 = Object.assign({\\"./modules/a.ts\\": () => import(\\"./modules/a.ts\\"),\\"./modules/b.ts\\": () => import(\\"./modules/b.ts\\"),\\"../fixture-b/a.ts\\": () => import(\\"../fixture-b/a.ts\\"),\\"../fixture-b/b.ts\\": () => import(\\"../fixture-b/b.ts\\")});
 "
 `;
 
 exports[`fixture > virtual modules 1`] = `
-"Object.assign({
-\\"/modules/a.ts\\": () => import(\\"/modules/a.ts\\"),
-\\"/modules/b.ts\\": () => import(\\"/modules/b.ts\\"),
-\\"/modules/index.ts\\": () => import(\\"/modules/index.ts\\")
-})
-Object.assign({
-\\"/../fixture-b/a.ts\\": () => import(\\"/../fixture-b/a.ts\\"),
-\\"/../fixture-b/b.ts\\": () => import(\\"/../fixture-b/b.ts\\"),
-\\"/../fixture-b/index.ts\\": () => import(\\"/../fixture-b/index.ts\\")
-})"
+"Object.assign({\\"/modules/a.ts\\": () => import(\\"/modules/a.ts\\"),\\"/modules/b.ts\\": () => import(\\"/modules/b.ts\\"),\\"/modules/index.ts\\": () => import(\\"/modules/index.ts\\")})
+Object.assign({\\"/../fixture-b/a.ts\\": () => import(\\"/../fixture-b/a.ts\\"),\\"/../fixture-b/b.ts\\": () => import(\\"/../fixture-b/b.ts\\"),\\"/../fixture-b/index.ts\\": () => import(\\"/../fixture-b/index.ts\\")})"
 `;
diff --git a/packages/vite/src/node/plugins/assetImportMetaUrl.ts b/packages/vite/src/node/plugins/assetImportMetaUrl.ts
@@ -3,7 +3,7 @@ import MagicString from 'magic-string'
 import { stripLiteral } from 'strip-literal'
 import type { Plugin } from '../plugin'
 import type { ResolvedConfig } from '../config'
-import { transformResult } from '../utils'
+import { transformStableResult } from '../utils'
 import { fileToUrl } from './asset'
 import { preloadHelperId } from './importAnalysisBuild'
 
@@ -81,7 +81,7 @@ export function assetImportMetaUrlPlugin(config: ResolvedConfig): Plugin {
           )
         }
         if (s) {
-          return transformResult(s, id, config)
+          return transformStableResult(s, id, config)
         }
       }
       return null

diff --git a/packages/vite/src/node/plugins/define.ts b/packages/vite/src/node/plugins/define.ts
@@ -1,7 +1,7 @@
 import MagicString from 'magic-string'
-import type { TransformResult } from 'rollup'
 import type { ResolvedConfig } from '../config'
 import type { Plugin } from '../plugin'
+import { transformStableResult } from '../utils'
 import { isCSSRequest } from './css'
 import { isHTMLRequest } from './html'
 
@@ -144,11 +144,7 @@ export function definePlugin(config: ResolvedConfig): Plugin {
         return null
       }
 
-      const result: TransformResult = { code: s.toString() }
-      if (config.build.sourcemap) {
-        result.map = s.generateMap({ hires: true })
-      }
-      return result
+      return transformStableResult(s, id, config)
     }
   }
 }
diff --git a/packages/vite/src/node/plugins/dynamicImportVars.ts b/packages/vite/src/node/plugins/dynamicImportVars.ts
@@ -11,7 +11,7 @@ import {
   normalizePath,
   parseRequest,
   requestQuerySplitRE,
-  transformResult
+  transformStableResult
 } from '../utils'
 
 export const dynamicImportHelperId = '/@vite/dynamic-import-helper'
@@ -209,7 +209,7 @@ export function dynamicImportVarsPlugin(config: ResolvedConfig): Plugin {
             `import __variableDynamicImportRuntimeHelper from "${dynamicImportHelperId}";`
           )
         }
-        return transformResult(s, importer, config)
+        return transformStableResult(s, importer, config)
       }
     }
   }

diff --git a/packages/vite/src/node/plugins/importAnalysis.ts b/packages/vite/src/node/plugins/importAnalysis.ts
@@ -40,7 +40,7 @@ import {
   removeImportQuery,
   stripBomTag,
   timeFrom,
-  transformResult,
+  transformStableResult,
   unwrapId
 } from '../utils'
 import type { ResolvedConfig } from '../config'
@@ -711,7 +711,7 @@ export function importAnalysisPlugin(config: ResolvedConfig): Plugin {
       }
 
       if (s) {
-        return transformResult(s, importer, config)
+        return transformStableResult(s, importer, config)
       } else {
         return source
       }

diff --git a/packages/vite/src/node/plugins/importMetaGlob.ts b/packages/vite/src/node/plugins/importMetaGlob.ts
@@ -17,7 +17,7 @@ import type { Plugin } from '../plugin'
 import type { ViteDevServer } from '../server'
 import type { ModuleNode } from '../server/moduleGraph'
 import type { ResolvedConfig } from '../config'
-import { normalizePath, slash, transformResult } from '../utils'
+import { normalizePath, slash, transformStableResult } from '../utils'
 
 const { isMatch, scan } = micromatch
 
@@ -75,7 +75,7 @@ export function importGlobPlugin(config: ResolvedConfig): Plugin {
             server!.watcher.add(dirname(file))
           })
         }
-        return transformResult(result.s, id, config)
+        return transformStableResult(result.s, id, config)
       }
     }
   }
@@ -426,7 +426,7 @@ export async function transformGlobImport(
 
           files.forEach((i) => matchedFiles.add(i))
 
-          const replacement = `Object.assign({\n${objectProps.join(',\n')}\n})`
+          const replacement = `Object.assign({${objectProps.join(',')}})`
           s.overwrite(start, end, replacement)
 
           return staticImports
@@ -435,7 +435,7 @@ export async function transformGlobImport(
     )
   ).flat()
 
-  if (staticImports.length) s.prepend(`${staticImports.join('\n')}\n`)
+  if (staticImports.length) s.prepend(`${staticImports.join(';')};`)
 
   return {
     s,

diff --git a/packages/vite/src/node/plugins/workerImportMetaUrl.ts b/packages/vite/src/node/plugins/workerImportMetaUrl.ts
@@ -10,7 +10,7 @@ import {
   injectQuery,
   normalizePath,
   parseRequest,
-  transformResult
+  transformStableResult
 } from '../utils'
 import { getDepsOptimizer } from '../optimizer'
 import type { WorkerType } from './worker'
@@ -136,7 +136,7 @@ export function workerImportMetaUrlPlugin(config: ResolvedConfig): Plugin {
         }
 
         if (s) {
-          return transformResult(s, id, config)
+          return transformStableResult(s, id, config)
         }
 
         return null

diff --git a/packages/vite/src/node/utils.ts b/packages/vite/src/node/utils.ts
@@ -1028,16 +1028,21 @@ function normalizeSingleAlias({
   return alias
 }
 
-export function transformResult(
+/**
+ * Transforms transpiled code result where line numbers aren't altered,
+ * so we can skip sourcemap generation during dev
+ */
+export function transformStableResult(
   s: MagicString,
   id: string,
   config: ResolvedConfig
 ): TransformResult {
-  const isBuild = config.command === 'build'
-  const needSourceMap = !isBuild || config.build.sourcemap
   return {
     code: s.toString(),
-    map: needSourceMap ? s.generateMap({ hires: true, source: id }) : null
+    map:
+      config.command === 'build' && config.build.sourcemap
+        ? s.generateMap({ hires: true, source: id })
+        : null
   }
 }