fix: inherit concurrent/sequential in nested suites (#4482)

docs/api/index.md

@@ -654,7 +654,7 @@ You cannot use this syntax, when using Vitest as [type checker](/guide/testing-t
 
 - **Type:** `(name: string | Function, fn: TestFunction, options?: number | TestOptions) => void`
 
-`describe.sequential` in a suite marks every test as sequential. This is useful if you want to run tests in sequential within `describe.concurrent` or with the `--sequence.concurrent` command option.
+`describe.sequential` in a suite marks every test as sequential. This is useful if you want to run tests in sequence within `describe.concurrent` or with the `--sequence.concurrent` command option.
 
 ```ts
 describe.concurrent('suite', () => {

packages/runner/src/suite.ts

@@ -80,7 +80,7 @@ function createSuiteCollector(name: string, factory: SuiteFactory = () => { }, m
       meta: options.meta ?? Object.create(null),
     }
     const handler = options.handler
-    if (options.concurrent || (!sequential && (concurrent || runner.config.sequence.concurrent)))
+    if (options.concurrent || (!options.sequential && runner.config.sequence.concurrent))
       task.concurrent = true
     if (shuffle)
       task.shuffle = true
@@ -104,14 +104,18 @@ function createSuiteCollector(name: string, factory: SuiteFactory = () => { }, m
     return task
   }
 
-  const test = createTest(function (name: string | Function, fn = noop, options) {
+  const test = createTest(function (name: string | Function, fn = noop, options = {}) {
     if (typeof options === 'number')
       options = { timeout: options }
 
     // inherit repeats, retry, timeout from suite
     if (typeof suiteOptions === 'object')
       options = Object.assign({}, suiteOptions, options)
 
+    // inherit concurrent / sequential from suite
+    options.concurrent = this.concurrent || (!this.sequential && options?.concurrent)
+    options.sequential = this.sequential || (!this.concurrent && options?.sequential)
+
     const test = task(
       formatName(name),
       { ...this, ...options, handler: fn as any },
@@ -188,7 +192,7 @@ function createSuiteCollector(name: string, factory: SuiteFactory = () => { }, m
 }
 
 function createSuite() {
-  function suiteFn(this: Record<string, boolean | undefined>, name: string | Function, factory?: SuiteFactory, options?: number | TestOptions) {
+  function suiteFn(this: Record<string, boolean | undefined>, name: string | Function, factory?: SuiteFactory, options: number | TestOptions = {}) {
     const mode: RunMode = this.only ? 'only' : this.skip ? 'skip' : this.todo ? 'todo' : 'run'
     const currentSuite = getCurrentSuite()
 
@@ -199,7 +203,11 @@ function createSuite() {
     if (currentSuite?.options)
       options = { ...currentSuite.options, ...options }
 
-    return createSuiteCollector(formatName(name), factory, mode, this.concurrent, this.sequence, this.shuffle, this.each, options)
+    // inherit concurrent / sequential from current suite
+    options.concurrent = this.concurrent || (!this.sequential && options?.concurrent)
+    options.sequential = this.sequential || (!this.concurrent && options?.sequential)
+
+    return createSuiteCollector(formatName(name), factory, mode, this.concurrent, this.sequential, this.shuffle, this.each, options)
   }
 
   suiteFn.each = function<T>(this: { withContext: () => SuiteAPI; setContext: (key: string, value: boolean | undefined) => SuiteAPI }, cases: ReadonlyArray<T>, ...args: any[]) {

packages/runner/src/types/tasks.ts

@@ -178,6 +178,16 @@ export interface TestOptions {
    * @default 0
    */
   repeats?: number
+  /**
+   * Whether tests run concurrently.
+   * Tests inherit `concurrent` from `describe()` and nested `describe()` will inherit from parent's `concurrent`.
+   */
+  concurrent?: boolean
+  /**
+   * Whether tests run sequentially.
+   * Tests inherit `sequential` from `describe()` and nested `describe()` will inherit from parent's `sequential`.
+   */
+  sequential?: boolean
 }
 
 interface ExtendedAPI<ExtraContext> {

packages/vitest/src/types/config.ts

@@ -813,6 +813,11 @@ export type RuntimeConfig = Pick<
   | 'restoreMocks'
   | 'fakeTimers'
   | 'maxConcurrency'
-> & { sequence?: { hooks?: SequenceHooks } }
+> & {
+  sequence?: {
+    concurrent?: boolean
+    hooks?: SequenceHooks
+  }
+}
 
 export type { UserWorkspaceConfig } from '../config'

test/core/test/sequential-sequence-concurrent.test.ts

@@ -0,0 +1,24 @@
+import { describe, expect, test, vi } from 'vitest'
+
+vi.setConfig({
+  sequence: {
+    concurrent: true,
+  },
+})
+
+const delay = (timeout: number) => new Promise(resolve => setTimeout(resolve, timeout))
+
+let count = 0
+
+describe.sequential('running sequential suite when sequence.concurrent is true', () => {
+  test('first test completes first', async ({ task }) => {
+    await delay(50)
+    expect(task.concurrent).toBeFalsy()
+    expect(++count).toBe(1)
+  })
+
+  test('second test completes second', ({ task }) => {
+    expect(task.concurrent).toBeFalsy()
+    expect(++count).toBe(2)
+  })
+})

test/core/test/sequential.test.ts

@@ -2,19 +2,59 @@ import { describe, expect, test } from 'vitest'
 
 const delay = (timeout: number) => new Promise(resolve => setTimeout(resolve, timeout))
 
-let count = 0
-
-describe.concurrent('', () => {
-  describe.sequential('', () => {
-    test('should pass', async ({ task }) => {
-      await delay(50)
-      expect(task.concurrent).toBeFalsy()
-      expect(++count).toBe(1)
-    })
-
-    test('should pass', ({ task }) => {
-      expect(task.concurrent).toBeFalsy()
-      expect(++count).toBe(2)
-    })
+function assertSequential() {
+  let count = 0
+
+  test('first test completes first', async ({ task }) => {
+    await delay(50)
+    expect(task.concurrent).toBeFalsy()
+    expect(++count).toBe(1)
+  })
+
+  test('second test completes second', ({ task }) => {
+    expect(task.concurrent).toBeFalsy()
+    expect(++count).toBe(2)
+  })
+
+  test.concurrent('third test completes fourth', async ({ task }) => {
+    await delay(50)
+    expect(task.concurrent).toBe(true)
+    expect(++count).toBe(4)
+  })
+
+  test.concurrent('fourth test completes third', ({ task }) => {
+    expect(task.concurrent).toBe(true)
+    expect(++count).toBe(3)
+  })
+}
+
+function assertConcurrent() {
+  let count = 0
+
+  test('first test completes second', async ({ task }) => {
+    await delay(50)
+    expect(task.concurrent).toBe(true)
+    expect(++count).toBe(2)
+  })
+
+  test('second test completes first', ({ task }) => {
+    expect(task.concurrent).toBe(true)
+    expect(++count).toBe(1)
+  })
+}
+
+assertSequential()
+
+describe.concurrent('describe.concurrent', () => {
+  assertConcurrent()
+
+  describe('describe', assertConcurrent)
+
+  describe.sequential('describe.sequential', () => {
+    assertSequential()
+
+    describe('describe', assertSequential)
+
+    describe.concurrent('describe.concurrent', assertConcurrent)
   })
 })