blob: 1b90e8e12d26eb9c519e133cca1c559ab658f10c [file] [log] [blame]
// Copyright 2019 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.
import fs from 'fs';
import path from 'path';
import {parse, print} from 'recast';
import {promisify} from 'util';
const readFile = promisify(fs.readFile);
const stat = promisify(fs.stat);
const FRONT_END_FOLDER = path.join(__dirname, '..', '..', 'front_end');
// eslint-disable-next-line @typescript-eslint/no-explicit-any
export async function getMappings(namespace: string, mappings: Map<string, any>, useExternalRefs = false) {
const src = namespace.toLocaleLowerCase();
const externalModule = path.join(FRONT_END_FOLDER, src, `${src}.js`);
const legacy = path.join(FRONT_END_FOLDER, src, `${src}-legacy.js`);
if (!(await stat(legacy))) {
console.error(`Unable to find legacy file: ${legacy}`);
process.exit(1);
}
const legacyFileContents = await readFile(legacy, { encoding: 'utf-8' });
const ast = parse(legacyFileContents);
for (const statement of ast.program.body) {
if (statement.type !== 'ExpressionStatement') {
continue;
}
// We need to check that we have an assignment expression, of which the left and right are both member expressions.
// This allows us to extract things like Foo.Bar = FooModule.Bar.Bar from the legacy file, while ignoring self.Foo
// and Foo = Foo || {} statements.
const isMemberExpressionOnLeftAndRight = statement.expression && statement.expression.left &&
statement.expression.right && statement.expression.type === 'AssignmentExpression' &&
statement.expression.left.type === 'MemberExpression' && statement.expression.right.type === 'MemberExpression';
if (isMemberExpressionOnLeftAndRight) {
// Rename FooModule back to Foo because we know we will want to use the latter when doing replacements.
if (statement.expression.right.object && statement.expression.right.object.object &&
statement.expression.right.object.object.type === 'Identifier') {
statement.expression.right.object.object.name = statement.expression.right.object.object.name.replace(/Module$/, '');
}
const leftSide = print(statement.expression.left).code;
const rightSide = print(statement.expression.right).code;
const rightSideParts = rightSide.split('.');
const file = useExternalRefs ? externalModule : path.join(FRONT_END_FOLDER, src, rightSideParts[1] + '.js');
if (rightSideParts[0] === 'Protocol') {
rightSideParts[0] = 'ProtocolClient';
}
mappings.set(leftSide, {
file,
replacement: rightSideParts.join('.'),
sameFolderReplacement: rightSideParts[rightSideParts.length - 1],
});
}
}
return mappings;
}