fix(coverage): infer transform mode for uncovered files (#9435)

AriPerkkio · web-flow · commit f396792d6952 · 2026-01-13T15:32:50.000+01:00
diff --git a/packages/vitest/src/node/coverage.ts b/packages/vitest/src/node/coverage.ts
@@ -634,15 +634,16 @@ export class BaseCoverageProvider<Options extends ResolvedCoverageOptions<'istan
         root: project.config.root,
         isBrowserEnabled: project.isBrowserEnabled(),
         vite: project.vite,
+        environment: project.config.environment,
       })),
       // Check core last as it will match all files anyway
-      { root: ctx.config.root, vite: ctx.vite, isBrowserEnabled: ctx.getRootProject().isBrowserEnabled() },
+      { root: ctx.config.root, vite: ctx.vite, isBrowserEnabled: ctx.getRootProject().isBrowserEnabled(), environment: ctx.config.environment },
     ]
 
     return async function transformFile(filename: string): Promise<TransformResult | null | undefined> {
       let lastError
 
-      for (const { root, vite, isBrowserEnabled } of servers) {
+      for (const { root, vite, isBrowserEnabled, environment } of servers) {
         // On Windows root doesn't start with "/" while filenames do
         if (!filename.startsWith(root) && !filename.startsWith(`/${root}`)) {
           continue
@@ -657,14 +658,18 @@ export class BaseCoverageProvider<Options extends ResolvedCoverageOptions<'istan
         }
 
         try {
+          if (environment === 'jsdom' || environment === 'happy-dom') {
+            return await vite.environments.client.transformRequest(filename)
+          }
+
           return await vite.environments.ssr.transformRequest(filename)
         }
         catch (error) {
           lastError = error
         }
       }
 
-      // All vite-node servers failed to transform the file
+      // All vite servers failed to transform the file
       throw lastError
     }
   }
diff --git a/test/coverage-test/fixtures/configs/vitest.config.conditional.ts b/test/coverage-test/fixtures/configs/vitest.config.conditional.ts
@@ -1,4 +1,4 @@
-import { join, resolve } from 'node:path'
+import { resolve } from 'node:path'
 import { defineConfig } from 'vitest/config'
 
 export default defineConfig({
@@ -9,9 +9,9 @@ export default defineConfig({
         replacement: "$1",
         customResolver(_, __, options) {
           if ('ssr' in options && options.ssr) {
-            return { id: resolve('fixtures/src/conditional/node.ts') }
+            return { id: resolve('fixtures/src/conditional/ssr.ts') }
           }
-          return { id: resolve('fixtures/src/conditional/browser.ts') }
+          return { id: resolve('fixtures/src/conditional/web.ts') }
         },
       },
     ],
diff --git a/test/coverage-test/fixtures/src/conditional/browser.ts b/test/coverage-test/fixtures/src/conditional/browser.ts
diff --git a/test/coverage-test/fixtures/src/conditional/node.ts b/test/coverage-test/fixtures/src/conditional/node.ts
diff --git a/test/coverage-test/fixtures/src/conditional/ssr.ts b/test/coverage-test/fixtures/src/conditional/ssr.ts
@@ -0,0 +1,3 @@
+export function ssr() {
+  return "This is for ssr transform"
+}
diff --git a/test/coverage-test/fixtures/src/conditional/web.ts b/test/coverage-test/fixtures/src/conditional/web.ts
@@ -0,0 +1,3 @@
+export function web() {
+  return "This is for web transform"
+}
diff --git a/test/coverage-test/test/include-exclude.test.ts b/test/coverage-test/test/include-exclude.test.ts
@@ -225,7 +225,7 @@ test('overridden exclude should still apply defaults', async () => {
   expect(coverageMap.files()).toMatchInlineSnapshot(`{}`)
 })
 
-test('uncovered files are transformed correctly', async () => {
+test('uncovered files are transformed correctly (node and browser)', async () => {
   await runVitest({
     config: 'fixtures/configs/vitest.config.conditional.ts',
     include: ['fixtures/test/math.test.ts'],
@@ -242,20 +242,44 @@ test('uncovered files are transformed correctly', async () => {
     expect(files).toMatchInlineSnapshot(`
       [
         "<process-cwd>/fixtures/src/math.ts",
-        "<process-cwd>/fixtures/src/conditional/browser.ts",
+        "<process-cwd>/fixtures/src/conditional/web.ts",
       ]
     `)
   }
   else {
     expect(files).toMatchInlineSnapshot(`
       [
         "<process-cwd>/fixtures/src/math.ts",
-        "<process-cwd>/fixtures/src/conditional/node.ts",
+        "<process-cwd>/fixtures/src/conditional/ssr.ts",
       ]
     `)
   }
 })
 
+test('uncovered files are transformed correctly (jsdom)', async ({ skip }) => {
+  skip(isBrowser(), 'node relevant test')
+
+  await runVitest({
+    config: 'fixtures/configs/vitest.config.conditional.ts',
+    include: ['fixtures/test/math.test.ts'],
+    environment: 'jsdom',
+    coverage: {
+      include: ['fixtures/src/math.ts', 'fixtures/src/conditional/*'],
+      reporter: 'json',
+    },
+  })
+
+  const coverageMap = await readCoverageMap()
+  const files = coverageMap.files()
+
+  expect(files).toMatchInlineSnapshot(`
+      [
+        "<process-cwd>/fixtures/src/math.ts",
+        "<process-cwd>/fixtures/src/conditional/web.ts",
+      ]
+    `)
+})
+
 test('files included and excluded in plugin\'s configureVitest are excluded', async () => {
   await runVitest({
     config: 'fixtures/configs/vitest.config.configure-vitest-hook.ts',

Original file line number	Diff line number	Diff line change
`@@ -634,15 +634,16 @@ export class BaseCoverageProvider<Options extends ResolvedCoverageOptions<'istan`
`634`	`634`	`root: project.config.root,`
`635`	`635`	`isBrowserEnabled: project.isBrowserEnabled(),`
`636`	`636`	`vite: project.vite,`
	`637`	`+ environment: project.config.environment,`
`637`	`638`	`})),`
`638`	`639`	`// Check core last as it will match all files anyway`
`639`		`- { root: ctx.config.root, vite: ctx.vite, isBrowserEnabled: ctx.getRootProject().isBrowserEnabled() },`
	`640`	`+ { root: ctx.config.root, vite: ctx.vite, isBrowserEnabled: ctx.getRootProject().isBrowserEnabled(), environment: ctx.config.environment },`
`640`	`641`	`]`
`641`	`642`
`642`	`643`	`return async function transformFile(filename: string): Promise<TransformResult \| null \| undefined> {`
`643`	`644`	`let lastError`
`644`	`645`
`645`		`- for (const { root, vite, isBrowserEnabled } of servers) {`
	`646`	`+ for (const { root, vite, isBrowserEnabled, environment } of servers) {`
`646`	`647`	`// On Windows root doesn't start with "/" while filenames do`
`647`	`648`	if (!filename.startsWith(root) && !filename.startsWith(`/${root}`)) {
`648`	`649`	`continue`
`@@ -657,14 +658,18 @@ export class BaseCoverageProvider<Options extends ResolvedCoverageOptions<'istan`
`657`	`658`	`}`
`658`	`659`
`659`	`660`	`try {`
	`661`	`+ if (environment === 'jsdom' \|\| environment === 'happy-dom') {`
	`662`	`+ return await vite.environments.client.transformRequest(filename)`
	`663`	`+ }`
	`664`	`+`
`660`	`665`	`return await vite.environments.ssr.transformRequest(filename)`
`661`	`666`	`}`
`662`	`667`	`catch (error) {`
`663`	`668`	`lastError = error`
`664`	`669`	`}`
`665`	`670`	`}`
`666`	`671`
`667`		`- // All vite-node servers failed to transform the file`
	`672`	`+ // All vite servers failed to transform the file`
`668`	`673`	`throw lastError`
`669`	`674`	`}`
`670`	`675`	`}`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+export function ssr() {`
	`2`	`+ return "This is for ssr transform"`
	`3`	`+}`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+export function web() {`
	`2`	`+ return "This is for web transform"`
	`3`	`+}`