feat(coverage): add coverage.changed option to report only changed files (#9521)

Co-authored-by: Ari Perkkiö <ari.perkkio@gmail.com>

Author: kykim00

docs/config/coverage.md

@@ -405,3 +405,12 @@ Directory of HTML coverage output to be served in [Vitest UI](/guide/ui) and [HT
 This is automatically configured when using builtin coverage reporters that produce HTML output (`html`, `html-spa`, and `lcov`). Use this option to override with a custom coverage reporting location when using custom coverage reporters.
 
 Note that setting this option does not change where coverage HTML report is generated. Configure the `coverage.reporter` option to change the directory instead.
+
+## coverage.changed
+
+- **Type:** `boolean | string`
+- **Default:** `false` (inherits from `test.changed`)
+- **Available for providers:** `'v8' | 'istanbul'`
+- **CLI:** `--coverage.changed`, `--coverage.changed=<commit/branch>`
+
+Collect coverage only for files changed since a specified commit or branch. When set to `true`, it uses staged and unstaged changes.

docs/guide/cli-generated.md

@@ -278,6 +278,13 @@ High and low watermarks for branches in the format of `<high>,<low>`
 
 High and low watermarks for functions in the format of `<high>,<low>`
 
+### coverage.changed
+
+- **CLI:** `--coverage.changed <commit/branch>`
+- **Config:** [coverage.changed](/config/coverage#coverage-changed)
+
+Collect coverage only for files changed since a specified commit or branch (e.g., `origin/main` or `HEAD~1`). Inherits value from `--changed` by default.
+
 ### mode
 
 - **CLI:** `--mode <name>`

packages/vitest/src/node/cli/cli-config.ts

@@ -306,6 +306,20 @@ export const cliOptionsConfig: VitestCLIOptions = {
  },
  },
  },
+ changed: {
+ description:
+ 'Collect coverage only for files changed since a specified commit or branch (e.g., `origin/main` or `HEAD~1`). Inherits value from `--changed` by default.',
+ argument: '<commit/branch>',
+ transform(value) {
+ if (value === 'true' || value === 'yes' || value === true) {
+ return true
+ }
+ if (value === 'false' || value === 'no' || value === false) {
+ return false
+ }
+ return value
+ },
+ },
  },
  },
  mode: {

packages/vitest/src/node/config/resolveConfig.ts

@@ -419,6 +419,9 @@ export function resolveConfig(
  }
 
  resolved.coverage.reporter = resolveCoverageReporters(resolved.coverage.reporter)
+ if (resolved.coverage.changed === undefined && resolved.changed !== undefined) {
+ resolved.coverage.changed = resolved.changed
+ }
 
  if (resolved.coverage.enabled && resolved.coverage.reportsDirectory) {
  const reportsDirectory = resolve(

packages/vitest/src/node/core.ts

@@ -607,6 +607,7 @@ export class Vitest {
  }
 
  await this._testRun.start(specifications).catch(noop)
+ await this.coverageProvider?.onTestRunStart?.()
 
  for (const file of files) {
  await this._reportFileTask(file)
@@ -749,6 +750,7 @@ export class Vitest {
  if (!specifications.length) {
  await this._traces.$('vitest.test_run', async () => {
  await this._testRun.start([])
+ await this.coverageProvider?.onTestRunStart?.()
  const coverage = await this.coverageProvider?.generateCoverage?.({ allTestsRun: true })
 
  await this._testRun.end([], [], coverage)
@@ -880,6 +882,7 @@ export class Vitest {
  private async runFiles(specs: TestSpecification[], allTestsRun: boolean): Promise<TestRunResult> {
  return this._traces.$('vitest.test_run', async () => {
  await this._testRun.start(specs)
+ await this.coverageProvider?.onTestRunStart?.()
 
  // previous run
  await this.cancelPromise

packages/vitest/src/node/coverage.ts

@@ -9,7 +9,7 @@ import { existsSync, promises as fs, readdirSync, writeFileSync } from 'node:fs'
 import module from 'node:module'
 import path from 'node:path'
 import { fileURLToPath } from 'node:url'
-import { slash } from '@vitest/utils/helpers'
+import { cleanUrl, slash } from '@vitest/utils/helpers'
 import { relative, resolve } from 'pathe'
 import pm from 'picomatch'
 import { glob } from 'tinyglobby'
@@ -86,6 +86,7 @@ export class BaseCoverageProvider<Options extends ResolvedCoverageOptions<'istan
  pendingPromises: Promise<void>[] = []
  coverageFilesDirectory!: string
  roots: string[] = []
+ changedFiles?: string[]
 
  _initialize(ctx: Vitest): void {
  this.ctx = ctx
@@ -148,7 +149,7 @@ export class BaseCoverageProvider<Options extends ResolvedCoverageOptions<'istan
  isIncluded(_filename: string, root?: string): boolean {
  const roots = root ? [root] : this.roots
 
- const filename = slash(_filename)
+ const filename = slash(cleanUrl(_filename))
  const cacheHit = this.globCache.get(filename)
 
  if (cacheHit !== undefined) {
@@ -165,12 +166,16 @@ export class BaseCoverageProvider<Options extends ResolvedCoverageOptions<'istan
  // By default `coverage.include` matches all files, except "coverage.exclude"
  const glob = this.options.include || '**'
 
- const included = pm.isMatch(filename, glob, {
+ let included = pm.isMatch(filename, glob, {
  contains: true,
  dot: true,
  ignore: this.options.exclude,
  })
 
+ if (included && this.changedFiles) {
+ included = this.changedFiles.includes(filename)
+ }
+
  this.globCache.set(filename, included)
 
  return included
@@ -192,8 +197,8 @@ export class BaseCoverageProvider<Options extends ResolvedCoverageOptions<'istan
  // Run again through picomatch as tinyglobby's exclude pattern is different ({ "exclude": ["math"] } should ignore "src/math.ts")
  includedFiles = includedFiles.filter(file => this.isIncluded(file, root))
 
- if (this.ctx.config.changed) {
- includedFiles = (this.ctx.config.related || []).filter(file => includedFiles.includes(file))
+ if (this.changedFiles) {
+ includedFiles = this.changedFiles.filter(file => includedFiles.includes(file))
  }
 
  return includedFiles.map(file => slash(path.resolve(root, file)))
@@ -324,6 +329,23 @@ export class BaseCoverageProvider<Options extends ResolvedCoverageOptions<'istan
  }
  }
 
+ async onTestRunStart(): Promise<void> {
+ if (this.options.changed) {
+ const { VitestGit } = await import('./git')
+ const vitestGit = new VitestGit(this.ctx.config.root)
+ const changedFiles = await vitestGit.findChangedFiles({ changedSince: this.options.changed })
+
+ this.changedFiles = changedFiles ?? undefined
+ }
+ else if (this.ctx.config.changed) {
+ this.changedFiles = this.ctx.config.related
+ }
+
+ if (this.changedFiles) {
+ this.globCache.clear()
+ }
+ }
+
  async onTestFailure(): Promise<void> {
  if (!this.options.reportOnFailure) {
  await this.cleanAfterRun()

packages/vitest/src/node/types/coverage.ts

@@ -28,7 +28,10 @@ export interface CoverageProvider {
  /** Called with coverage results after a single test file has been run */
  onAfterSuiteRun: (meta: AfterSuiteRunMeta) => void | Promise<void>
 
- /** Callback called when test run fails */
+ /** Callback called when test run starts */
+ onTestRunStart?: () => void | Promise<void>
+
+ /** Callback called when test run fails due to test failures */
  onTestFailure?: () => void | Promise<void>
 
  /** Callback to generate final coverage results */
@@ -274,14 +277,22 @@ export interface BaseCoverageOptions {
  * Use this option to override with custom coverage reporting location.
  */
  htmlDir?: string
+
+ /**
+ * Collect coverage only for files changed since a specified commit or branch.
+ * Inherits the default value from `test.changed`.
+ *
+ * @default false
+ */
+ changed?: boolean | string
 }
 
 export interface CoverageIstanbulOptions extends BaseCoverageOptions {}
 
 export interface CoverageV8Options extends BaseCoverageOptions {}
 
 export interface CustomProviderOptions
- extends Pick<BaseCoverageOptions, FieldsWithDefaultValues> {
+ extends Pick<BaseCoverageOptions, FieldsWithDefaultValues | 'changed'> {
  /** Name of the module or path to a file to load the custom provider from */
  customProviderModule: string
 }

test/config/test/public.test.ts

@@ -117,3 +117,23 @@ test.for([
  expected && resolve(vitestConfig.root, expected),
  )
 })
+
+test('coverage.changed inherits from test.changed but can be overridden', async () => {
+ const { vitestConfig: inherited } = await resolveConfig({
+ changed: 'HEAD',
+ coverage: {
+ reporter: 'json',
+ },
+ })
+
+ expect(inherited.coverage.changed).toBe('HEAD')
+
+ const { vitestConfig: overridden } = await resolveConfig({
+ changed: 'HEAD',
+ coverage: {
+ changed: false,
+ },
+ })
+
+ expect(overridden.coverage.changed).toBe(false)
+})

test/core/test/cli-test.test.ts

@@ -60,6 +60,7 @@ test('nested coverage options have correct types', async () => {
  --coverage.thresholds.100 25
 
  --coverage.provider v8
+ --coverage.changed HEAD
  --coverage.reporter text
  --coverage.reportsDirectory .\\dist\\coverage
  --coverage.customProviderModule=./folder/coverage.js
@@ -81,6 +82,7 @@ test('nested coverage options have correct types', async () => {
  enabled: true,
  reporter: ['text'],
  provider: 'v8',
+ changed: 'HEAD',
  clean: false,
  cleanOnRerun: true,
  reportsDirectory: 'dist/coverage',

test/coverage-test/test/changed.test.ts

@@ -68,3 +68,99 @@ test('{ changed: "HEAD" }', { skip: SKIP }, async () => {
  }
  `)
 })
+
+test('{ coverage.changed: "HEAD" }', async () => {
+ await runVitest({
+ include: [
+ 'fixtures/test/file-to-change.test.ts',
+ 'fixtures/test/math.test.ts',
+ ],
+ coverage: {
+ include: [
+ 'fixtures/src/file-to-change.ts',
+ 'fixtures/src/new-uncovered-file.ts',
+
+ // Should not show up
+ 'fixtures/src/untested-file.ts',
+ 'fixtures/src/math.ts',
+ ],
+ reporter: 'json',
+ changed: 'HEAD',
+ },
+ })
+
+ const coverageMap = await readCoverageMap()
+
+ expect(coverageMap.files()).toMatchInlineSnapshot(`
+ [
+ "<process-cwd>/fixtures/src/file-to-change.ts",
+ "<process-cwd>/fixtures/src/new-uncovered-file.ts",
+ ]
+ `)
+})
+
+test('{ coverage.changed: "HEAD", excludeAfterRemap: true }', async () => {
+ await runVitest({
+ include: [
+ 'fixtures/test/file-to-change.test.ts',
+ 'fixtures/test/math.test.ts',
+ ],
+ coverage: {
+ include: [
+ 'fixtures/src/file-to-change.ts',
+ 'fixtures/src/new-uncovered-file.ts',
+
+ // Should not show up
+ 'fixtures/src/untested-file.ts',
+ 'fixtures/src/math.ts',
+ ],
+ reporter: 'json',
+ changed: 'HEAD',
+ excludeAfterRemap: true,
+ },
+ })
+
+ const coverageMap = await readCoverageMap()
+
+ expect(coverageMap.files()).toMatchInlineSnapshot(`
+ [
+ "<process-cwd>/fixtures/src/file-to-change.ts",
+ "<process-cwd>/fixtures/src/new-uncovered-file.ts",
+ ]
+ `)
+})
+
+test('{ changed: "v0.0.1", coverage.changed: "HEAD" }', async () => {
+ await runVitest({
+ include: [
+ 'fixtures/test/file-to-change.test.ts',
+ 'fixtures/test/math.test.ts',
+ ],
+
+ // v0.0.1 is an actual git tag in Vitest repository
+ changed: 'v0.0.1',
+
+ coverage: {
+ include: [
+ 'fixtures/src/file-to-change.ts',
+ 'fixtures/src/new-uncovered-file.ts',
+
+ // Should not show up
+ 'fixtures/src/untested-file.ts',
+ 'fixtures/src/math.ts',
+ ],
+ reporter: 'json',
+ changed: 'HEAD',
+ },
+ })
+
+ const coverageMap = await readCoverageMap()
+
+ // Should show changes since HEAD, not v0.0.1
+ expect(coverageMap.files()).toMatchInlineSnapshot(`
+ [
+ "<process-cwd>/fixtures/src/file-to-change.ts",
+ "<process-cwd>/fixtures/src/new-uncovered-file.ts",
+ ]
+ `)
+})