ci: block major changesets

Author: petebacondarwin

.github/workflows/major-release-validation.yml

@@ -0,0 +1,46 @@
+name: Major release validation
+
+on:
+  merge_group:
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  check:
+    concurrency:
+      group: ${{ github.workflow }}-${{ github.ref }}-${{ matrix.os }}-major-release-validation
+      cancel-in-progress: true
+
+    name: "Major release validation"
+    runs-on: ubuntu-24.04-arm
+    steps:
+      - name: Checkout Repo
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 100
+
+      # Find all the changesets that were modified or added in this pull request
+      - uses: dorny/paths-filter@v3
+        id: filters
+        with:
+          list-files: "json"
+          predicate-quantifier: "every"
+          filters: |
+            updated_changesets:
+              - added|modified: '.changeset/*.md'
+              - added|modified: '!.changeset/README.md'
+
+      - name: Install Dependencies
+        if: steps.filters.outputs.updated_changesets == 'true'
+        uses: ./.github/actions/install-dependencies
+
+      # Validate that the pull request is marked with the appropriate label if any of the modified or added changesets have major releases
+      - name: Validate major changes
+        if: steps.filters.outputs.updated_changesets == 'true'
+        run: node -r esbuild-register tools/deployments/validate-major-changes.ts
+        with:
+          GITHUB_TOKEN: ${{ github.token }}
+          CHANGES: ${{ steps.filters.outputs.updated_changesets_files }}
+          LABEL: "breaking-change"

tools/deployments/validate-major-changesets.ts

@@ -0,0 +1,71 @@
+import { readFileSync } from "node:fs";
+import core from "@actions/core";
+import { context, getOctokit } from "@actions/github";
+import parseChangesetFile from "@changesets/parse";
+
+if (require.main === module) {
+	main().catch((err) => {
+		console.error("Unexpected error:", err);
+		process.exit(1);
+	});
+}
+
+async function main() {
+	const majorChangesets = getMajorChangesets();
+	const breakingChangeLabel = core.getInput("label", { required: true });
+	const hasBreakingChangeLabel = await hasLabel(breakingChangeLabel);
+
+	if (majorChangesets.length === 0) {
+		if (hasBreakingChangeLabel) {
+			core.error(
+				`This PR is marked with the "${breakingChangeLabel}" but does not contain any major release changesets.`
+			);
+			process.exit(1);
+		}
+	} else {
+		if (!hasBreakingChangeLabel) {
+			core.error(
+				`This PR contains the following changesets that have major releases, but is not marked with the "${breakingChangeLabel}" label`
+			);
+			majorChangesets.forEach((changeset) => {
+				core.info(
+					` - "${changeset.file}": ${changeset.summary.split("\n")[0]}`
+				);
+			});
+			process.exit(1);
+		}
+	}
+}
+
+/**
+ * Returns an array of parsed changesets that contain at least one major release
+ */
+export function getMajorChangesets() {
+	const files = JSON.parse(
+		core.getInput("changes", { required: true })
+	) as string[];
+
+	const changesets = files.map((file) => ({
+		file,
+		...parseChangesetFile(readFileSync(file, "utf-8")),
+	}));
+	return changesets.filter((parsed) =>
+		parsed.releases.some((r) => r.type === "major")
+	);
+}
+
+/**
+ * Returns true of the current issue/pr has the given label
+ */
+export async function hasLabel(label: string) {
+	const token = core.getInput("github_token", { required: true });
+
+	const octokit = getOctokit(token);
+	const issue = await octokit.rest.issues.get({
+		...context.repo,
+		issue_number: context.issue.number,
+	});
+	return !!issue.data.labels.find(
+		(l) => (typeof l !== "string" && l.name === label) || l === label
+	);
+}