Add a script to generate a changelog

scripts/changelog.js

@@ -0,0 +1,54 @@
+const exec = require('child_process').execSync;
+const spawn = require('child_process').spawnSync;
+const fs = require('fs');
+
+let packages = JSON.parse(exec('yarn workspaces info --json').toString().split('\n').slice(1, -2).join('\n'));
+
+let commits = new Map();
+
+// Diff each package individually. Some packages might have been skipped during last release,
+// so we cannot simply look at the last tag on the whole repo.
+for (let name in packages) {
+  let filePath = packages[name].location + '/package.json';
+  let pkg = JSON.parse(fs.readFileSync(filePath, 'utf8'));
+  if (!pkg.private) {
+    // Diff this package since the last published version, according to the package.json.
+    // The release script creates a tag for each package version.
+    let tag = `${pkg.name}@${pkg.version}`;
+
+    let args = [
+      'log',
+      `${tag}..HEAD`,
+      '--pretty="%H%x00%aI%x00%an%x00%s"',
+      packages[name].location,
+
+      // filter out non-code changes
+      ':!**/test/**',
+      ':!**/stories/**',
+      ':!**/chromatic/**'
+    ];
+
+    let res = spawn('git', args, {encoding: 'utf8'});
+    if (res.stdout.length === 0) {
+      continue;
+    }
+
+    for (let line of res.stdout.split('\n')) {
+      if (line === '') {
+        continue;
+      }
+
+      let info = line.replace(/^"|"$/g, '').split('\0');
+      commits.set(info[0], info);
+    }
+  }
+}
+
+let sortedCommits = [...commits.values()].sort((a, b) => a[1] < b[1] ? -1 : 1);
+
+for (let commit of sortedCommits) {
+  let m = commit[3].match(/(.*?) \(#(\d+)\)$/);
+  let message = m?.[1] || commit[3];
+  let pr = m ? `https://github.com/adobe/react-spectrum/pull/${m[2]}` : null;
+  console.log(`* ${message} - ${commit[2]}` + (pr ? ` - [PR](${pr})` : ''));
+}