check-and-rewrite-package-json.js

/*
 * Copyright (c) 2024, Salesforce, Inc.
 * All rights reserved.
 * SPDX-License-Identifier: MIT
 * For full license text, see the LICENSE file in the repo root or https://opensource.org/licenses/MIT
 */

// Checks that various package.json files are structured the way we expect.
// Errors if the files are different, and writes the changed files to disk.
//
// The goals are:
// 1. to avoid having to manually keep package.json files in sync with each other
// 2. to have a consistent format for all the package.jsons we publish to npm
//
// Use the flag `--test` if you want it to fail with a non-zero exit code if the package.json
// files differ from what we expect.

const fs = require('node:fs');
const path = require('node:path');
const { globSync } = require('glob');

// This is the same list as in @lwc/rollup-plugin/src/index.ts
const LWC_EXPOSED_MODULES = {
    '@lwc/engine-dom': ['lwc'],
    '@lwc/synthetic-shadow': ['@lwc/synthetic-shadow'],
    '@lwc/wire-service': [
        '@lwc/wire-service',
        // TODO [#3517]: remove support for deprecated 'wire-service' import
        'wire-service',
    ],
};

/**
 * Packages with static content that don't need to be built. The `lwc` package is not included
 * because this script file only updates `@lwc/` packages.
 */
const STATIC_PACKAGES = ['@lwc/types'];

const expectedPkgJsons = [];

for (const dir of globSync('./packages/@lwc/*')) {
    const filename = path.join('./', dir, 'package.json');
    const actual = fs.readFileSync(filename, 'utf-8');
    const pkg = JSON.parse(actual);
    // Skip private packages
    if (pkg.private) {
        continue;
    }

    const { name, description, version, dependencies, devDependencies, peerDependencies } = pkg;
    let { keywords } = pkg;

    // Keywords aren't really important, but keep any that already exist and add 'lwc'
    keywords = [...new Set((keywords || []).concat(['lwc']))].sort();

    let buildProps;
    if (STATIC_PACKAGES.includes(name)) {
        // Static packages may or may not define all of these props; we don't need to worry about
        // that because JSON.stringify automatically drops anything undefined.
        buildProps = {
            main: pkg.main,
            module: pkg.module,
            types: pkg.types,
            files: pkg.files,
            scripts: pkg.scripts,
            nx: pkg.nx,
        };
    } else {
        buildProps = {
            main: 'dist/index.cjs.js',
            module: 'dist/index.js',
            types: 'dist/index.d.ts',
            // It's important _not_ to use `./dist` here (with the `./`), because npm does not understand that
            files: Array.from(new Set(['dist/**/*.js', 'dist/**/*.d.ts', ...pkg.files])),
            scripts: {
                build: 'rollup --config ../../../scripts/rollup/rollup.config.js',
                dev: 'rollup  --config ../../../scripts/rollup/rollup.config.js --watch --no-watch.clearScreen',
            },
            nx: {
                targets: {
                    build: {
                        // It's important to use the `./` here, otherwise NX does not restore the dist files
                        // See https://github.com/salesforce/lwc/issues/3511
                        outputs: ['{projectRoot}/dist'],
                    },
                },
            },
        };
    }

    const expectedJson = {
        '//': [
            'THIS FILE IS AUTOGENERATED. If you modify it, it will be rewritten by check-and-rewrite-package-json.js',
            'You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten.',
        ],
        name,
        version,
        description,
        keywords,
        homepage: 'https://lwc.dev',
        repository: {
            type: 'git',
            url: 'https://github.com/salesforce/lwc.git',
            directory: `packages/${name}`,
        },
        bugs: { url: 'https://github.com/salesforce/lwc/issues' },
        license: 'MIT',
        publishConfig: { access: 'public' },
        // Use the same volta config in every subdirectory so that we always get the same node/yarn versions
        // See: https://docs.volta.sh/advanced/workspaces
        volta: {
            extends: '../../../package.json',
        },
        ...buildProps,
        dependencies,
        devDependencies,
        peerDependencies,
    };

    const exposedModules = LWC_EXPOSED_MODULES[name];
    if (exposedModules) {
        // Special case - consumers can do `import { LightningElement } from 'lwc'` and have it resolve to
        // `@lwc/engine-dom`. As for @lwc/synthetic-shadow and @lwc/wire-service, we have historically included these in
        // the "default modules" defined in @lwc/rollup-plugin.
        expectedJson.lwc = {
            modules: exposedModules.map((exposedModule) => ({
                name: exposedModule,
                path: 'dist/index.js',
            })),
            expose: exposedModules,
        };
    }

    const expected = JSON.stringify(expectedJson, null, 4) + '\n';

    expectedPkgJsons.push({
        filename,
        expected,
        actual,
    });
}

// Check if any of the files are different than what we expect, so we can error in that case
const differingPackageJsonFiles = [];

for (const { filename, expected, actual } of expectedPkgJsons) {
    if (actual !== expected) {
        differingPackageJsonFiles.push(filename);
        fs.writeFileSync(filename, expected, 'utf-8');
    }
}

if (differingPackageJsonFiles.length > 0) {
    console.error(
        'Found package.json files with unexpected content. Content has been overwritten.\n' +
            'Please run `git commit` and `node ./scripts/tasks/check-and-rewrite-package-json.js` again.\n' +
            'Files:',
        differingPackageJsonFiles
    );
    // Only in "test" mode do we actually emit a non-zero exit code. This is designed for CI tests.
    // In other cases (e.g. as a git precommit hook), we can just exit with a normal 0 exit code.
    if (process.argv.includes('--test')) {
        process.exitCode = 1;
    }
}