// Copyright 2023 The Chromium Authors // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. import {createHash} from 'node:crypto'; import * as fs from 'node:fs'; import * as os from 'node:os'; import * as path from 'node:path'; import * as DiffUtils from './diff-utils.js'; import {GEN_DIR, SOURCE_ROOT} from './paths.js'; export type ArtifactGroup = Record; export class ScreenshotError extends Error { // The max length of the summary is 4000, but we need to leave some room for // the rest of the HTML formatting (e.g.

and

). static readonly SUMMARY_LENGTH_CUTOFF = 3900; static errors: ScreenshotError[] = []; readonly screenshots: ArtifactGroup; screenshotPath?: string; private constructor(screenshots: ArtifactGroup, message?: string, cause?: Error, screenshotPath?: string) { message = [message, cause?.message, (cause?.cause as Error)?.message].filter(x => x).join('\n\n'); super(message); this.cause = cause; this.stack = cause?.stack ?? ''; this.screenshots = screenshots; // To show Diffs mocha Spec reporter expects some properties. // See node_modules/mocha/lib/reporters/base.js. // @ts-expect-error forwarding error properties for Mocha. this.showDiff = cause?.showDiff; // @ts-expect-error forwarding error properties for Mocha. this.actual = cause?.actual; // @ts-expect-error forwarding error properties for Mocha. this.expected = cause?.expected; // @ts-expect-error forwarding error properties for Mocha. this.operator = cause?.operator; this.screenshotPath = screenshotPath; } /** * Creates a ScreenshotError when a reference golden does not exists. */ static fromGeneratedScreenshot(message: string, generatedImgPath: string) { const screenshots = { generated: {filePath: this.stashArtifact(generatedImgPath, 'generated')}, }; const screenshotPath = path.join('test/goldens', path.relative(path.join(GEN_DIR, 'test/.generated'), generatedImgPath)); return new ScreenshotError(screenshots, message, undefined, screenshotPath); } /** * Creates a ScreenshotError when a generated screenshot is different from * the golden. */ static fromScreenshotAssertionError( error: Error, goldenImgPath: string, generatedImgPath: string, diffImgPath: string) { const screenshots = { expected_image: {filePath: this.stashArtifact(goldenImgPath, 'expected')}, actual_image: {filePath: this.stashArtifact(generatedImgPath, 'actual')}, image_diff: {filePath: this.stashArtifact(diffImgPath, 'diff')}, }; const screenshotPath = path.relative(SOURCE_ROOT, goldenImgPath); return new ScreenshotError(screenshots, undefined, error, screenshotPath); } /** * Creates a ScreenshotError when an unexpected error occurs. Screenshots are * taken for both the inspected page and the DevTools page. */ static fromBase64Images( error: Error, inspectedPageScreenshot?: string, devToolsPageScreenshot?: string, collectedScreenshots?: Record): Error { if (!inspectedPageScreenshot || !devToolsPageScreenshot) { console.error('No artifacts to save.'); return error; } const screenshots: ArtifactGroup = { inspectedPage: {filePath: this.saveArtifact(inspectedPageScreenshot)}, devToolsPage: {filePath: this.saveArtifact(devToolsPageScreenshot)}, ...ScreenshotError.saveArtifacts(collectedScreenshots) }; return new ScreenshotError(screenshots, undefined, error); } static saveArtifacts(collectedScreenshots: Record|undefined) { const screenshots: ArtifactGroup = {}; for (const name in collectedScreenshots) { screenshots[name] = {filePath: this.saveArtifact(collectedScreenshots[name])}; } return screenshots; } /** * Costructs a summary for Milo at resultdb publication time. */ toMiloSummary(): string { if ('expected_image' in this.screenshots) { // no summary; autogenerated by Milo based on artifact name convention return ''; } if ('generated' in this.screenshots) { // TODO(liviurau): embed image once Milo supports it return '

' + this.message.slice(0, ScreenshotError.SUMMARY_LENGTH_CUTOFF) +
          '

Screenshot generated (see below)

'; } // TODO(liviurau): embed images once Milo supports it const message = (this.message + '\n\n' + this.stack); const assertionDiff = DiffUtils.resultAssertionsDiff([this]); const diffText = DiffUtils.formatDiffText(assertionDiff); let summary = DiffUtils.formatSummary(message, diffText, ScreenshotError.SUMMARY_LENGTH_CUTOFF); summary += '

Unexpected error. See inspected and DevTools pages screenshots below.

'; return summary; } /** * Copy artifacts in tmp folder so they remain available * at resultdb publication time. */ private static stashArtifact(originalFile: string, tag: string): string { const stashedFileName = tag + '-' + path.basename(originalFile); const artifactPath = path.join(os.tmpdir(), stashedFileName); fs.copyFileSync(originalFile, artifactPath); return artifactPath; } /** * Save base64 image in tmp folder to make it available at resultdb * publication time. */ private static saveArtifact(base64Image: string): string { base64Image = base64Image.replace(/^data:image\/png;base64,/, ''); const fileName = createHash('sha256').update(base64Image).digest('hex'); const artifactPath = path.join(os.tmpdir(), fileName); fs.writeFileSync(artifactPath, base64Image, {encoding: 'base64'}); return artifactPath; } } /* eslint-disable-next-line @typescript-eslint/no-explicit-any */ export const ScreenshotErrorReporter = function(this: any, baseReporterDecorator: (arg0: unknown) => void) { const JSON_PATH = path.join(GEN_DIR, 'test', '.generated', 'errors.js'); baseReporterDecorator(this); this.onRunComplete = () => { const screenshotErrors = ScreenshotError.errors.splice(0).map( /* eslint-disable-next-line @typescript-eslint/naming-convention */ ({screenshotPath, screenshots: {expected_image, actual_image, image_diff}}) => ({screenshotPath, expected_image, actual_image, image_diff})); fs.writeFileSync(JSON_PATH, `window.SCREENSHOT_ERRORS = ${JSON.stringify(screenshotErrors)}`); }; }; ScreenshotErrorReporter.$inject = ['baseReporterDecorator'];