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		cfe92e1608
		
			
		
	
	
	
	
		
			
			This patch implements `expect.poll()` method that polls given
predicate until a given synchronous predicate completes.
Usage:
```js
// wait until page gets 3 frames.
await expect.poll(() => page.frames().length, {
  timeout: 1000,
  message: 'custom error message',
}).toBe(3);
```
Fixes #10235
		
	
			
		
			
				
	
	
		
			147 lines
		
	
	
		
			4.8 KiB
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
			
		
		
	
	
			147 lines
		
	
	
		
			4.8 KiB
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
| /**
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|  * Copyright Microsoft Corporation. All rights reserved.
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|  *
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|  * Licensed under the Apache License, Version 2.0 (the "License");
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|  * you may not use this file except in compliance with the License.
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|  * You may obtain a copy of the License at
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|  *
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|  *     http://www.apache.org/licenses/LICENSE-2.0
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|  *
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|  * Unless required by applicable law or agreed to in writing, software
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|  * distributed under the License is distributed on an "AS IS" BASIS,
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|  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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|  * See the License for the specific language governing permissions and
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|  * limitations under the License.
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|  */
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| 
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| import { test, expect, stripAnsi } from './playwright-test-fixtures';
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| 
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| test('should poll predicate', async ({ runInlineTest }) => {
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|   const result = await runInlineTest({
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|     'a.spec.ts': `
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|       const { test } = pwt;
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|       test('should poll sync predicate', async () => {
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|         let i = 0;
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|         await test.expect.poll(() => ++i).toBe(3);
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|       });
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|       test('should poll async predicate', async () => {
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|         let i = 0;
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|         await test.expect.poll(async () => {
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|           await new Promise(x => setTimeout(x, 50));
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|           return ++i;
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|         }).toBe(3);
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|       });
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|       test('should poll predicate that returns a promise', async () => {
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|         let i = 0;
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|         await test.expect.poll(() => Promise.resolve(++i)).toBe(3);
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|       });
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|     `
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|   });
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|   expect(result.exitCode).toBe(0);
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|   expect(result.passed).toBe(3);
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| });
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| 
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| test('should compile', async ({ runTSC }) => {
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|   const result = await runTSC({
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|     'a.spec.ts': `
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|       const { test } = pwt;
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|       test('should poll sync predicate', () => {
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|         let i = 0;
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|         test.expect.poll(() => ++i).toBe(3);
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|         test.expect.poll(() => ++i, 'message').toBe(3);
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|         test.expect.poll(() => ++i, { message: 'message' }).toBe(3);
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|         test.expect.poll(() => ++i, { timeout: 100 }).toBe(3);
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|         test.expect.poll(() => ++i, { message: 'message', timeout: 100 }).toBe(3);
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|         test.expect.poll(async () => {
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|           await new Promise(x => setTimeout(x, 50));
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|           return ++i;
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|         }).toBe(3);
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|         test.expect.poll(() => Promise.resolve(++i)).toBe(3);
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|       });
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|     `
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|   });
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|   expect(result.exitCode).toBe(0);
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| });
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| 
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| test('should respect timeout', async ({ runInlineTest }) => {
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|   const result = await runInlineTest({
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|     'a.spec.ts': `
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|       const { test } = pwt;
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|       test('should fail', async () => {
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|         await test.expect.poll(() => false, { timeout: 100 }).toBe(3);
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|       });
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|     `
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|   });
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|   expect(result.exitCode).toBe(1);
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|   expect(stripAnsi(result.output)).toContain('Timeout 100ms exceeded while waiting on the predicate');
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|   expect(stripAnsi(result.output)).toContain(`
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|   7 |         await test.expect.poll(() => false, { timeout: 100 }).
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|   `.trim());
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| });
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| 
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| test('should fail when passed in non-function', async ({ runInlineTest }) => {
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|   const result = await runInlineTest({
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|     'a.spec.ts': `
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|       const { test } = pwt;
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|       test('should fail', async () => {
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|         await test.expect.poll(false).toBe(3);
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|       });
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|     `
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|   });
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|   expect(result.exitCode).toBe(1);
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|   expect(stripAnsi(result.output)).toContain('Error: `expect.poll()` accepts only function as a first argument');
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| });
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| 
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| test('should fail when used with web-first assertion', async ({ runInlineTest }) => {
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|   const result = await runInlineTest({
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|     'a.spec.ts': `
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|       const { test } = pwt;
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|       test('should fail', async ({ page }) => {
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|         await test.expect.poll(() => page.locator('body')).toHaveText('foo');
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|       });
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|     `
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|   });
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|   expect(result.exitCode).toBe(1);
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|   expect(stripAnsi(result.output)).toContain('Error: `expect.poll()` does not support "toHaveText" matcher');
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| });
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| 
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| test('should time out when running infinite predicate', async ({ runInlineTest }) => {
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|   const result = await runInlineTest({
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|     'a.spec.ts': `
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|       const { test } = pwt;
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|       test('should fail', async ({ page }) => {
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|         await test.expect.poll(() => new Promise(x => {}), { timeout: 100 }).toBe(42);
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|       });
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|     `
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|   });
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|   expect(result.exitCode).toBe(1);
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|   expect(stripAnsi(result.output)).toContain('Timeout 100ms exceeded');
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| });
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| 
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| test('should show error that is thrown from predicate', async ({ runInlineTest }) => {
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|   const result = await runInlineTest({
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|     'a.spec.ts': `
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|       const { test } = pwt;
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|       test('should fail', async ({ page }) => {
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|         await test.expect.poll(() => { throw new Error('foo bar baz'); }, { timeout: 100 }).toBe(42);
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|       });
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|     `
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|   });
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|   expect(result.exitCode).toBe(1);
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|   expect(stripAnsi(result.output)).toContain('foo bar baz');
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| });
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| 
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| test('should support .not predicate', async ({ runInlineTest }) => {
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|   const result = await runInlineTest({
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|     'a.spec.ts': `
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|       const { test } = pwt;
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|       test('should fail', async ({ page }) => {
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|         let i = 0;
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|         await test.expect.poll(() => ++i).not.toBeLessThan(3);
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|         expect(i).toBe(3);
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|       });
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|     `
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|   });
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|   expect(result.exitCode).toBe(0);
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| });
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