feat(sync): synchronise versions across multiple package.json

Author: JamieMason

.babelrc

@@ -1,11 +1,7 @@
 {
   "presets": ["es2015"],
   "plugins": [
-    [
-      "fast-async",
-      {
-        "useRuntimeModule": true
-      }
-    ]
+    ["fast-async", { "useRuntimeModule": true }],
+    "transform-object-rest-spread"
   ]
 }

README.md

@@ -7,8 +7,45 @@
 [![Join the chat at https://gitter.im/JamieMason/syncpack](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/JamieMason/syncpack)
 [![Analytics](https://ga-beacon.appspot.com/UA-45466560-5/syncpack?flat&useReferer)](https://github.com/igrigorik/ga-beacon)
 
-Normalise differences across multiple `package.json` files, such as `packages/*/package.json` in [Lerna](https://lernajs.io) Monorepos.
+Synchronises the versions of dependencies used across multiple `package.json` files, such as
+`packages/*/package.json` in [Lerna](https://lernajs.io) Monorepos.
 
-## Status
+## Overview
 
-In Development, not yet ready for use.
+Imagine the packages `guybrush`, `herman`, and `elaine` all have `react` as a dependency, but
+versions `'15.4.0'`, `'15.5.4'`, and `'15.6.1'` respectively.
+
+```
+/Users/foldleft/Dev/monorepo/packages/
+├── guybrush
+│   └── package.json
+├── herman
+│   └── package.json
+└── elaine
+    └── package.json
+```
+
+Running `syncpack` will update each `package.json` to use version `'15.6.1'` of `react` in
+`dependencies`, `devDependencies`, and `peerDependencies` as needed.
+
+## Installation
+
+```
+npm install --global syncpack
+```
+
+## Usage
+
+### Command Line
+
+```
+Usage: syncpack [options] [pattern]
+
+Options:
+
+  -h, --help     output usage information
+  -V, --version  output the version number
+```
+
+The default pattern of `'./packages/*/package.json'` can be overridden as follows
+`syncpack './**/package.json'`

package-lock.json

@@ -17,6 +17,7 @@
   },
   "devDependencies": {
     "babel-cli": "6.24.1",
+    "babel-plugin-transform-object-rest-spread": "6.26.0",
     "babel-preset-es2015": "6.22.0",
     "fast-async": "6.3.0",
     "rimraf": "2.5.4",

package.json

@@ -6,10 +6,17 @@ import { version } from '../package.json';
 import * as log from './lib/log';
 import syncpack from './index';
 
-program.version(version);
+let patternValue;
+
+program.version(version).arguments('[pattern]').action(pattern => {
+  patternValue = pattern;
+});
+
 program.parse(process.argv);
 
-syncpack({}).catch(err => {
+syncpack({
+  pattern: patternValue
+}).catch(err => {
   log.bug('uncaught error in syncpack', err);
   process.exit(1);
 });

src/bin.js

@@ -1 +1,96 @@
-export default () => Promise.resolve();
+import bluebird from 'bluebird';
+import chalk from 'chalk';
+import path from 'path';
+import semver from 'semver';
+import * as log from './lib/log';
+import getFiles from './lib/get-files';
+import writeJson from './lib/write-json';
+
+const keys = (object = {}) => Object.keys(object);
+const clone = object => JSON.parse(JSON.stringify(object));
+const concatAll = arrayOfArrays => [].concat.apply([], arrayOfArrays);
+const entries = object => keys(object).map(key => [key, object[key]]);
+const isEmptyObject = object => keys(object).length === 0;
+const pluck = key => object => object[key];
+
+const stripWildCards = version => version.replace(/[*^=><]/g, '');
+const getPackage = location => ({ location: location, json: require(location) });
+const takeNewest = (max, next) =>
+  !semver.valid(stripWildCards(next)) || semver.gt(stripWildCards(next), stripWildCards(max))
+    ? next
+    : max;
+
+const indexEntries = array =>
+  array.reduce((index, [key, value]) => {
+    index[key] = index[key] || [];
+    index[key] = index[key].indexOf(value) === -1 ? index[key].concat(value) : index[key];
+    return index;
+  }, {});
+
+const getNewestDeps = (key, packages) => {
+  const dependencies = concatAll(packages.map(pluck('json')).map(pluck(key)).map(entries));
+  const versionsByDependencyName = indexEntries(dependencies);
+  return entries(versionsByDependencyName).map(([name, versions]) => {
+    const newest = versions.reduce(takeNewest, '0.0.0');
+    return [name, newest];
+  });
+};
+
+const getChangedDeps = (key, packages) =>
+  packages.map(pkg =>
+    getNewestDeps(key, packages).reduce((changes, [name, version]) => {
+      if (pkg.json[key] && name in pkg.json[key] && pkg.json[key][name] !== version) {
+        changes[name] = version;
+      }
+      return changes;
+    }, {})
+  );
+
+const reportChanges = (key, pkg, changes) => {
+  const changedEntries = entries(changes);
+  if (changedEntries.length) {
+    changedEntries.forEach(([name, version]) => {
+      console.log(`${key} ${name} ${chalk.red(pkg.json[key][name])} → ${chalk.green(version)}`);
+    });
+  } else {
+    console.log(`${key} ${chalk.green('✓ unchanged')}`);
+  }
+};
+
+export default async ({ pattern = './packages/*/package.json' }) => {
+  const packages = (await getFiles(pattern)).map(getPackage);
+  const changedDeps = getChangedDeps('dependencies', packages);
+  const changedDevDeps = getChangedDeps('devDependencies', packages);
+  const changedPeerDeps = getChangedDeps('peerDependencies', packages);
+
+  const nextPackages = packages.map(({ location, json }, i) => {
+    const nextPkg = {
+      location,
+      json: {
+        ...json,
+        dependencies: { ...json.dependencies, ...changedDeps[i] },
+        devDependencies: { ...json.devDependencies, ...changedDevDeps[i] },
+        peerDependencies: { ...json.peerDependencies, ...changedPeerDeps[i] }
+      }
+    };
+    if (isEmptyObject(nextPkg.json.dependencies)) {
+      delete nextPkg.json.dependencies;
+    }
+    if (isEmptyObject(nextPkg.json.devDependencies)) {
+      delete nextPkg.json.devDependencies;
+    }
+    if (isEmptyObject(nextPkg.json.peerDependencies)) {
+      delete nextPkg.json.peerDependencies;
+    }
+    return nextPkg;
+  });
+
+  packages.forEach((pkg, i) => {
+    console.log(chalk.grey.underline(path.relative(process.cwd(), pkg.location)));
+    reportChanges('dependencies', pkg, changedDeps[i]);
+    reportChanges('devDependencies', pkg, changedDevDeps[i]);
+    reportChanges('peerDependencies', pkg, changedPeerDeps[i]);
+  });
+
+  await bluebird.all(nextPackages.map(pkg => writeJson(pkg.location, pkg.json)));
+};

src/index.js

@@ -0,0 +1,13 @@
+import glob from 'glob';
+import * as log from './log';
+
+export default pattern =>
+  new Promise(resolve =>
+    glob(pattern, { absolute: true }, (err, files) => {
+      if (err) {
+        log.bug(`failed to search for files using pattern "${pattern}"`, err);
+        process.exit(1);
+      }
+      resolve(files);
+    })
+  );

src/lib/get-files.js

@@ -0,0 +1,8 @@
+import bluebird from 'bluebird';
+import fs from 'fs';
+
+export default async (location, contents) => {
+  const json = JSON.stringify(contents, null, 2);
+  const writeFile = bluebird.promisify(fs.writeFile);
+  return await writeFile(location, `${json}\n`, { encoding: 'utf8' });
+};