Script migration

third_party/WebKit/Source/devtools/scripts/migrate_test/migrate_test.js

Index: third_party/WebKit/Source/devtools/scripts/migrate_test/migrate_test.js
diff --git a/third_party/WebKit/Source/devtools/scripts/migrate_test/migrate_test.js b/third_party/WebKit/Source/devtools/scripts/migrate_test/migrate_test.js
new file mode 100644
index 0000000000000000000000000000000000000000..a8de6b6ec2b940aa12cf25a57fc1b6bf707b9a83
--- /dev/null
+++ b/third_party/WebKit/Source/devtools/scripts/migrate_test/migrate_test.js
@@ -0,0 +1,271 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+'use strict';
+
+const fs = require('fs');
+const path = require('path');
+
+const cheerio = require('cheerio');
+const mkdirp = require('mkdirp');
+const recast = require('recast');
+const types = recast.types;
+const b = recast.types.builders;
+const args = require('yargs')
+                 .wrap(Math.min(process.stdout.columns, 120))
+                 .example('node $0 existing-test.html')
+                 .boolean('dry-run')
+                 .help('help')
+                 .demand(1)
+                 .argv;
+
+const utils = require('../utils');
+
+const FRONT_END_PATH = path.resolve(__dirname, '..', '..', 'front_end');
+const LINE_BREAK = '$$SECRET_IDENTIFIER_FOR_LINE_BREAK$$();';
+
+function main() {
+  const inputPaths = args._;
+  const identifierMap = generateTestHelperMap();
+  for (const inputPath of inputPaths) {
+    console.log('Starting to migrate: ', inputPath);
+    migrateTest(inputPath, identifierMap);
+    console.log('Migrated: ', inputPath);
+  }
+  console.log(`Finished migrating ${inputPaths.length} tests`);
+}
+
+main();
+
+function migrateTest(inputPath, identifierMap) {
+  const htmlTestFile = fs.readFileSync(inputPath, 'utf-8');
+  const $ = cheerio.load(htmlTestFile);
+  const inputCode = $('script:not([src])')[0].children[0].data;
+  const bodyText = $('body').text().trim();
+  const helperScripts = $('script[src]').toArray().map((n) => n.attribs.src).map(src => {
+    const components = src.split('/');
+    return components[components.length - 1].split('.')[0];
+  });
+  const testHelpers = mapTestHelpers(helperScripts);
+  const domFixture = $('body')
+                         .html()
+                         .trim()
+                         // Tries to remove it if it has it's own line
+                         .replace(bodyText + '\n', '')
+                         // Tries to remove it if it's inline
+                         .replace(bodyText, '');
+  const outputCode =
+      transformTestScript(inputCode, bodyText, identifierMap, testHelpers, getPanel(inputPath), domFixture);
+  if (args.dryRun) {
+    console.log(outputCode);
+  } else {
+    const outPath = getOutPath(inputPath);
+    mkdirp.sync(path.dirname(outPath));
+    fs.writeFileSync(outPath, outputCode);
+  }
+}
+
+function transformTestScript(inputCode, bodyText, identifierMap, testHelpers, panel, domFixture) {
+  const ast = recast.parse(inputCode);
+  unwrapTestFunctionExpressionIfNecessary(ast);
+  unwrapTestFunctionDeclarationIfNecessary(ast);
+
+  /**
+   * Create test header based on extracted data
+   */
+  const headerLines = [];
+  headerLines.push(createExpressionNode(`TestRunner.addResult('${bodyText}\\n');`));
+  headerLines.push(createExpressionNode(LINE_BREAK));
+  for (const helper of testHelpers) {
+    headerLines.push(createAwaitExpressionNode(`await TestRunner.loadModule('${helper}');`));
+  }
+  headerLines.push(createAwaitExpressionNode(`await TestRunner.loadPanel('${panel}');`));
+  headerLines.push(createAwaitExpressionNode(`await TestRunner.loadHTML(\`
+${domFixture.split('\n').map(line => '    ' + line).join('\n')}
+  \`)`));
+  ast.program.body = headerLines.concat(ast.program.body);
+
+  /**
+   * Wrap entire body in an async IIFE
+   */
+  const iife = b.functionExpression(null, [], b.blockStatement(ast.program.body));
+  iife.async = true;
+  ast.program.body = [b.expressionStatement(b.callExpression(iife, []))];
+
+  /**
+   * Migrate all the call sites from InspectorTest to .*TestRunner
+   */
+  recast.visit(ast, {
+    visitIdentifier: function(path) {
+      if (path.parentPath && path.parentPath.value && path.parentPath.value.object &&
+          path.parentPath.value.object.name === 'InspectorTest' && path.value.name !== 'InspectorTest') {
+        const newParentIdentifier = identifierMap.get(path.value.name);
+        if (!newParentIdentifier) {
+          throw new Error('Could not find identifier for', path.value.name);
+        }
+        path.parentPath.value.object.name = newParentIdentifier;
+      }
+      return false;
+    }
+  });
+
+  return print(ast);
+}
+
+/**
+ * Unwrap test if it's a function expression
+ * var test = function () {...}
+ */
+function unwrapTestFunctionExpressionIfNecessary(ast) {
+  const index =
+      ast.program.body.findIndex(n => n.type === 'VariableDeclaration' && n.declarations[0].id.name === 'test');
+  if (index > -1) {
+    const testFunctionNode =
+        ast.program.body[index];
+    ast.program.body.splice(index, 1);
+    ast.program.body = ast.program.body.concat(testFunctionNode.declarations[0].init.body.body);
+  }
+}
+
+
+/**
+ * Unwrap test if it's a function declaration
+ * function test () {...}
+ */
+function unwrapTestFunctionDeclarationIfNecessary(ast) {
+  const index =
+      ast.program.body.findIndex(n => n.type === 'FunctionDeclaration' && n.id.name === 'test');
+  if (index > -1) {
+    const testFunctionNode =
+        ast.program.body[index];
+    ast.program.body.splice(index, 1);
+    ast.program.body = ast.program.body.concat(testFunctionNode.body.body);
+  }
+}
+
+function print(ast) {
+  const copyrightNotice = `// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+`;
+
+  /**
+   * Not using clang-format because certain tests look bad when formatted by it.
+   * Recast pretty print is smarter about preserving existing spacing.
+   */
+  const code = recast.prettyPrint(ast, {tabWidth: 2, wrapColumn: 120, quote: 'single'}).code;
+  return copyrightNotice + code.split(LINE_BREAK).join('') + '\n';
+}
+
+
+function getOutPath(inputPath) {
+  // TODO: Only works for non-http tests
+  const layoutTestPrefix = 'LayoutTests/inspector';
+  const postfix =
+      inputPath.slice(inputPath.indexOf(layoutTestPrefix) + layoutTestPrefix.length + 1).replace('.html', '.js');
+  const out =
+      path.resolve('.', '..', '..', '..', '..', 'LayoutTests', 'http', 'tests', 'inspector', 'devtools-js', postfix);
+  return out;
+}
+
+function getPanel(inputPath) {
+  const panelByFolder = {
+    'animation': 'elements',
+    'audits': 'audits',
+    'console': 'console',
+    'elements': 'elements',
+    'editor': 'sources',
+    'layers': 'layers',
+    'network': 'network',
+    'profiler': 'heap_profiler',
+    'resource-tree': 'resources',
+    'search': 'sources',
+    'security': 'security',
+    'service-workers': 'resources',
+    'sources': 'sources',
+    'timeline': 'timeline',
+    'tracing': 'timeline',
+  };
+  // Only works for non-http tests
+  const folder = inputPath.slice(inputPath.indexOf('LayoutTests/')).split('/')[2];
+  const panel = panelByFolder[folder];
+  if (!panel) {
+    throw new Error('Could not figure out which panel to map folder: ' + folder);
+  }
+  return panel;
+}
+
+function mapTestHelpers(testHelpers) {
+  const SKIP = 'SKIP';
+  const testHelperMap = {
+    'inspector-test': SKIP,
+    'console-test': 'console_test_runner',
+    'elements-test': 'elements_test_runner',
+  };
+  const mappedHelpers = [];
+  for (const helper of testHelpers) {
+    const mappedHelper = testHelperMap[helper];
+    if (!mappedHelper) {
+      throw Error('Could not map helper ' + helper);
+    }
+    if (mappedHelper !== SKIP) {
+      mappedHelpers.push(mappedHelper);
+    }
+  }
+  return mappedHelpers;
+}
+
+function generateTestHelperMap() {
+  const map = new Map();
+  for (const folder of fs.readdirSync(FRONT_END_PATH)) {
+    if (folder.indexOf('test_runner') === -1) {
+      continue;
+    }
+    const testRunnerModulePath = path.resolve(FRONT_END_PATH, folder);
+    if (!utils.isDir(testRunnerModulePath)) {
+      continue;
+    }
+    for (const filename of fs.readdirSync(testRunnerModulePath)) {
+      if (filename === 'module.json') {
+        continue;
+      }
+      scrapeTestHelperIdentifiers(path.resolve(testRunnerModulePath, filename));
+    }
+  }
+  return map;
+
+  function scrapeTestHelperIdentifiers(filePath) {
+    var content = fs.readFileSync(filePath).toString();
+    var lines = content.split('\n');
+    for (var line of lines) {
+      var line = line.trim();
+      if (line.indexOf('TestRunner.') === -1)
+        continue;
+      var match = line.match(/^(\b\w*TestRunner.[a-z_A-Z0-9]+)\s*(\=[^,}]|[;])/) ||
+          line.match(/^(TestRunner.[a-z_A-Z0-9]+)\s*\=$/);
+      if (!match)
+        continue;
+      var name = match[1];
+      var components = name.split('.');
+      if (components.length !== 2)
+        continue;
+      map.set(components[1], components[0]);
+    }
+  }
+}
+
+/**
+ * Hack to quickly create an AST node
+ */
+function createExpressionNode(code) {
+  return recast.parse(code).program.body[0];
+}
+
+/**
+ * Hack to quickly create an AST node
+ */
+function createAwaitExpressionNode(code) {
+  return recast.parse(`(async function(){${code}})`).program.body[0].expression.body.body[0];
+}