feat: add commands to run tests depending on changed files (#1078)

docs/config/index.md

@@ -422,3 +422,12 @@ Format options for snapshot testing.
 - **Default:** `test`
 
 Overrides Vite mode.
+
+### changed
+
+- **Type**: `boolean | string`
+- **Default**: false
+
+Run tests only against changed files. If no value is provided, it will run tests against uncomitted changes (includes staged and unstaged).
+
+To run tests against changes made in last commit, you can use `--changed HEAD~1`. You can also pass commit hash or branch name.

docs/guide/index.md

@@ -118,6 +118,7 @@ You can specify additional CLI options like `--port` or `--https`. For a full li
 | `--environment <env>` | Runner environment (default: `node`) |
 | `--passWithNoTests` | Pass when no tests found |
 | `--allowOnly` | Allow tests and suites that are marked as `only` (default: false in CI, true otherwise) |
+| `--changed [since]` | Run tests that are affected by the changed files (default: false)
 | `-h, --help` | Display available CLI options |
 
 ## Examples

packages/vitest/src/node/cli.ts

@@ -33,6 +33,7 @@ cli
   .option('--environment <env>', 'runner environment (default: node)')
   .option('--passWithNoTests', 'pass when no tests found')
   .option('--allowOnly', 'Allow tests and suites that are marked as only (default: !process.env.CI)')
+  .option('--changed [since]', 'Run tests that are affected by the changed files (default: false)')
   .help()
 
 cli

packages/vitest/src/node/config.ts

@@ -134,5 +134,8 @@ export function resolveConfig(
   if (!resolved.reporters.length)
     resolved.reporters.push('default')
 
+  if (resolved.changed)
+    resolved.passWithNoTests ??= true
+
   return resolved
 }

packages/vitest/src/node/core.ts

@@ -15,6 +15,7 @@ import type { WorkerPool } from './pool'
 import { StateManager } from './state'
 import { resolveConfig } from './config'
 import { printError } from './error'
+import { VitestGit } from './git'
 
 const WATCHER_DEBOUNCE = 100
 const CLOSE_TIMEOUT = 1_000
@@ -163,6 +164,18 @@ export class Vitest {
   }
 
   async filterTestsBySource(tests: string[]) {
+    if (this.config.changed && !this.config.related) {
+      const vitestGit = new VitestGit(this.config.root)
+      const related = await vitestGit.findChangedFiles({
+        changedSince: this.config.changed,
+      })
+      if (!related) {
+        this.error(c.red('Could not find Git root. Have you initialized git with `git init`?\n'))
+        process.exit(1)
+      }
+      this.config.related = Array.from(new Set(related))
+    }
+
     const related = this.config.related
     if (!related)
       return tests

packages/vitest/src/node/git.ts

@@ -0,0 +1,92 @@
+import { resolve } from 'pathe'
+import { execa } from 'execa'
+import type { ExecaReturnValue } from 'execa'
+
+export interface GitOptions {
+  changedSince?: string | boolean
+}
+
+export class VitestGit {
+  private root!: string
+
+  constructor(private cwd: string) {}
+
+  private async resolveFilesWithGitCommand(
+    args: string[],
+  ): Promise<string[]> {
+    let result: ExecaReturnValue
+
+    try {
+      result = await execa('git', args, { cwd: this.root })
+    }
+    catch (e: any) {
+      e.message = e.stderr
+
+      throw e
+    }
+
+    return result.stdout
+      .split('\n')
+      .filter(s => s !== '')
+      .map(changedPath => resolve(this.root, changedPath))
+  }
+
+  async findChangedFiles(options: GitOptions) {
+    const root = await this.getRoot(this.cwd)
+    if (!root)
+      return null
+
+    this.root = root
+
+    const changedSince = options.changedSince
+    if (typeof changedSince === 'string') {
+      const [committed, staged, unstaged] = await Promise.all([
+        this.getFilesSince(changedSince),
+        this.getStagedFiles(),
+        this.getUnstagedFiles(),
+      ])
+      return [...committed, ...staged, ...unstaged]
+    }
+    const [staged, unstaged] = await Promise.all([
+      this.getStagedFiles(),
+      this.getUnstagedFiles(),
+    ])
+    return [...staged, ...unstaged]
+  }
+
+  private getFilesSince(hash: string) {
+    return this.resolveFilesWithGitCommand(
+      ['diff', '--name-only', `${hash}...HEAD`],
+    )
+  }
+
+  private getStagedFiles() {
+    return this.resolveFilesWithGitCommand(
+      ['diff', '--cached', '--name-only'],
+    )
+  }
+
+  private getUnstagedFiles() {
+    return this.resolveFilesWithGitCommand(
+      [
+        'ls-files',
+        '--other',
+        '--modified',
+        '--exclude-standard',
+      ],
+    )
+  }
+
+  async getRoot(cwd: string) {
+    const options = ['rev-parse', '--show-cdup']
+
+    try {
+      const result = await execa('git', options, { cwd })
+
+      return resolve(cwd, result.stdout)
+    }
+    catch {
+      return null
+    }
+  }
+}

packages/vitest/src/types/config.ts

@@ -329,6 +329,13 @@ export interface UserConfig extends InlineConfig {
    * @default 'test'
    */
   mode?: string
+
+  /**
+   * Runs tests that are affected by the changes in the repository, or between specified branch or commit hash
+   * Requires initialized git repository
+   * @default false
+   */
+  changed?: boolean | string
 }
 
 export interface ResolvedConfig extends Omit<Required<UserConfig>, 'config' | 'filters' | 'coverage' | 'testNamePattern' | 'related' | 'api' | 'reporters'> {