feat(husky): add post pull hook to suggest running 'npm install' (mdn…

…#22308)

* feat(husky): add post pull hook to suggest running 'npm install'

* Rename to save-git-history

* update package.json

.husky/post-merge

@@ -0,0 +1,16 @@
+#!/usr/bin/env sh
+
+BRANCH="$(git rev-parse --abbrev-ref HEAD)"
+if [ "$BRANCH" != "main" ]; then
+  exit 0
+fi
+
+if [ -f ".husky/_/history" ]; then
+  lastHash=$(cat ./.husky/_/history)
+  isUpdated=$(git diff $lastHash HEAD -- ./package.json)
+  if [ "$isUpdated" != "" ]; then
+    echo "\n⚠🔥 'package.json' has changed. Please run 'npm install'! 🔥"
+  fi
+else
+  npm install
+fi

package.json

@@ -92,6 +92,7 @@
     "yargs": "~17.7.0"
   },
   "scripts": {
+    "postinstall": "node --loader=ts-node/esm --no-warnings=ExperimentalWarning scripts/save-git-history.ts",
     "prepare": "(husky || true) && npm run gentypes && npm run build",
     "diff": "node --loader=ts-node/esm --no-warnings=ExperimentalWarning scripts/diff.ts",
     "unittest": "NODE_ENV=test c8 mocha index.test.ts --recursive \"{,!(node_modules)/**}/*.test.ts\"",

scripts/lib/git.ts

@@ -59,4 +59,26 @@ const getFileContent = (commit: string, path: string): string =>
     })
     .trim();
 
-export { getMergeBase, getGitDiffStatuses, getFileContent };
+/**
+ * Get the current branch name
+ * @returns The output from the `git rev-parse --abbrev-ref HEAD` command
+ */
+const getBranchName = (): string =>
+  child_process
+    .execSync('git rev-parse --abbrev-ref HEAD', { encoding: 'utf-8' })
+    .trim();
+
+/**
+ * Get commit hash of HEAD
+ * @returns The output from the `git rev-parse HEAD` command
+ */
+const getHashOfHEAD = (): string =>
+  child_process.execSync('git rev-parse HEAD', { encoding: 'utf-8' }).trim();
+
+export {
+  getMergeBase,
+  getGitDiffStatuses,
+  getFileContent,
+  getBranchName,
+  getHashOfHEAD,
+};

scripts/save-git-history.ts

@@ -0,0 +1,15 @@
+/**
+ * This script stores the 'main' branch's HEAD commit hash in .husky/_/history
+ * The stored commit hash is used by the post-merge script .husky/post-merge
+ */
+
+import fs from 'node:fs';
+
+import { getBranchName, getHashOfHEAD } from './lib/git.js';
+
+const HUSKY_ROOT = '.husky/_/';
+const HISTORY_FILE = HUSKY_ROOT + 'history';
+
+if ('main' === getBranchName() && fs.existsSync(HUSKY_ROOT)) {
+  fs.writeFileSync(HISTORY_FILE, getHashOfHEAD());
+}