chore: create PR description from changeset

.github/pull_request_template.md

@@ -4,7 +4,7 @@ _Describe your change..._
 
 ---
 
-<!--
+<!-- START_CHECKLIST
 Please don't delete the checkboxes <3
 The following selections do not need to be completed if this PR only contains changes to .md files
 -->
@@ -22,4 +22,4 @@ The following selections do not need to be completed if this PR only contains ch
 <!--
 Have you read our [Contributing guide](https://github.com/cloudflare/workers-sdk/blob/main/CONTRIBUTING.md)?
 In particular, for non-trivial changes, please always engage on the issue or create a discussion or feature request issue first before writing your code.
--->
+END_CHECKLIST -->

.github/workflows/copy-changesets-to-pr.yml

@@ -0,0 +1,54 @@
+name: Copy Changesets to PR
+
+on:
+  pull_request:
+    types: [opened]
+    paths:
+      - ".changeset/*.md"
+
+jobs:
+  copy-changesets:
+    # Don't run on the Version Packages PR
+    if: github.head_ref != 'changeset-release/main'
+    runs-on: ubuntu-slim
+
+    permissions:
+      pull-requests: write
+      contents: read
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Get added changeset files
+        id: changesets
+        uses: dorny/paths-filter@v3
+        with:
+          list-files: json
+          filters: |
+            added:
+              - added: '.changeset/*.md'
+              - '!.changeset/README.md'
+
+      - name: Setup Node.js
+        if: steps.changesets.outputs.added == 'true'
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+
+      - name: Install pnpm
+        if: steps.changesets.outputs.added == 'true'
+        uses: pnpm/action-setup@v4
+        with:
+          version: 9.12.0
+
+      - name: Install Dependencies
+        if: steps.changesets.outputs.added == 'true'
+        run: pnpm i -F tools --frozen-lockfile
+
+      - name: Copy changesets to PR description
+        if: steps.changesets.outputs.added == 'true'
+        run: node -r esbuild-register tools/github-workflow-helpers/copy-changesets-to-pr.ts
+        env:
+          INPUT_GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          ADDED_CHANGESETS: ${{ steps.changesets.outputs.added_files }}

tools/github-workflow-helpers/__tests__/copy-changesets-to-pr.test.ts

@@ -0,0 +1,246 @@
+import * as fs from "node:fs";
+import * as path from "node:path";
+import { describe, expect, it } from "vitest";
+import {
+	formatChangesets,
+	insertChangesets,
+	isDescriptionEmpty,
+} from "../copy-changesets-to-pr";
+import type { Changeset } from "@changesets/types";
+
+// Read the actual PR template to keep tests in sync
+const FULL_TEMPLATE = fs.readFileSync(
+	path.join(__dirname, "../../../.github/pull_request_template.md"),
+	"utf-8"
+);
+
+describe("isDescriptionEmpty()", () => {
+	it("should return true for empty body", () => {
+		expect(isDescriptionEmpty("")).toBe(true);
+	});
+
+	it("should return true for body with only whitespace", () => {
+		expect(isDescriptionEmpty("   \n\n   ")).toBe(true);
+	});
+
+	it("should return true for template with only Fixes line", () => {
+		expect(isDescriptionEmpty("Fixes #123")).toBe(true);
+	});
+
+	it("should return true for full template with checklist", () => {
+		expect(isDescriptionEmpty(FULL_TEMPLATE)).toBe(true);
+	});
+
+	it("should return true for template with placeholder and separator", () => {
+		const body = `Fixes #123
+
+_Describe your change..._
+
+---
+`;
+		expect(isDescriptionEmpty(body)).toBe(true);
+	});
+
+	it("should return false when description has custom content (2+ lines)", () => {
+		const body = `Fixes #123
+
+This is my custom description.
+It has multiple lines.
+
+---
+`;
+		expect(isDescriptionEmpty(body)).toBe(false);
+	});
+
+	it("should return false when user added description to template", () => {
+		const body = `Fixes #456
+
+This PR adds a new feature that does something useful.
+It also fixes a bug.
+
+---
+
+<!-- START_CHECKLIST
+Please don't delete the checkboxes <3
+-->
+
+- Tests
+  - [x] Tests included/updated
+
+END_CHECKLIST -->
+`;
+		expect(isDescriptionEmpty(body)).toBe(false);
+	});
+
+	it("should handle body without checklist markers", () => {
+		const body = `Fixes #123
+
+_Describe your change..._
+
+---
+`;
+		expect(isDescriptionEmpty(body)).toBe(true);
+	});
+
+	it("should handle body without checklist markers but with content", () => {
+		const body = `Fixes #123
+
+This is a real description.
+With multiple lines.
+`;
+		expect(isDescriptionEmpty(body)).toBe(false);
+	});
+});
+
+describe("insertChangesets()", () => {
+	const changesetContent = `**Packages:** \`wrangler\` (patch)
+
+Fix a bug in the dev command`;
+
+	it("should replace placeholder when present", () => {
+		const body = `Fixes #123
+
+_Describe your change..._
+
+---
+`;
+		const result = insertChangesets(body, changesetContent);
+		expect(result).toBe(`Fixes #123
+
+**Packages:** \`wrangler\` (patch)
+
+Fix a bug in the dev command
+
+---
+`);
+		expect(result).not.toContain("_Describe your change..._");
+	});
+
+	it("should prepend when placeholder is not present", () => {
+		const body = `Fixes #123
+
+---
+`;
+		const result = insertChangesets(body, changesetContent);
+		expect(result).toBe(`**Packages:** \`wrangler\` (patch)
+
+Fix a bug in the dev command
+
+Fixes #123
+
+---
+`);
+	});
+
+	it("should prepend to empty body", () => {
+		const result = insertChangesets("", changesetContent);
+		expect(result).toBe(`**Packages:** \`wrangler\` (patch)
+
+Fix a bug in the dev command
+
+`);
+	});
+
+	it("should replace placeholder in full template", () => {
+		const result = insertChangesets(FULL_TEMPLATE, changesetContent);
+		expect(result).toContain("**Packages:** `wrangler` (patch)");
+		expect(result).toContain("Fix a bug in the dev command");
+		expect(result).not.toContain("_Describe your change..._");
+		// Should preserve the checklist
+		expect(result).toContain("<!-- START_CHECKLIST");
+		expect(result).toContain("END_CHECKLIST -->");
+	});
+});
+
+describe("formatChangesets()", () => {
+	it("should format a single changeset", () => {
+		const changesets: Changeset[] = [
+			{
+				summary: "Fix a bug in the dev command",
+				releases: [{ name: "wrangler", type: "patch" }],
+			},
+		];
+		const result = formatChangesets(changesets);
+		expect(result).toMatchInlineSnapshot(`
+			"#### Changeset 1
+			**Packages:** \`wrangler\` (patch)
+
+			Fix a bug in the dev command"
+		`);
+	});
+
+	it("should format multiple changesets with numbered headers", () => {
+		const changesets: Changeset[] = [
+			{
+				summary: "Fix a bug",
+				releases: [{ name: "wrangler", type: "patch" }],
+			},
+			{
+				summary: "Add a new feature",
+				releases: [{ name: "miniflare", type: "minor" }],
+			},
+		];
+		const result = formatChangesets(changesets);
+		expect(result).toMatchInlineSnapshot(`
+			"#### Changeset 1
+			**Packages:** \`wrangler\` (patch)
+
+			Fix a bug
+
+			#### Changeset 2
+			**Packages:** \`miniflare\` (minor)
+
+			Add a new feature"
+		`);
+	});
+
+	it("should list multiple packages in one changeset", () => {
+		const changesets: Changeset[] = [
+			{
+				summary: "Shared update across packages",
+				releases: [
+					{ name: "wrangler", type: "minor" },
+					{ name: "miniflare", type: "minor" },
+					{ name: "@cloudflare/vitest-pool-workers", type: "patch" },
+				],
+			},
+		];
+		const result = formatChangesets(changesets);
+		expect(result).toMatchInlineSnapshot(`
+			"#### Changeset 1
+			**Packages:** \`wrangler\` (minor), \`miniflare\` (minor), \`@cloudflare/vitest-pool-workers\` (patch)
+
+			Shared update across packages"
+		`);
+	});
+
+	it("should handle changeset with multi-line summary", () => {
+		const changesets: Changeset[] = [
+			{
+				summary: `Add new CLI command for database export
+
+You can now export your D1 database to a local SQL file:
+
+\`\`\`bash
+wrangler d1 export my-database --output backup.sql
+\`\`\`
+
+This is useful for creating backups.`,
+				releases: [{ name: "wrangler", type: "minor" }],
+			},
+		];
+		const result = formatChangesets(changesets);
+		expect(result).toContain("#### Changeset 1");
+		expect(result).toContain("`wrangler` (minor)");
+		expect(result).toContain("Add new CLI command for database export");
+		expect(result).toContain("```bash");
+		expect(result).toContain(
+			"wrangler d1 export my-database --output backup.sql"
+		);
+	});
+
+	it("should handle empty changesets array", () => {
+		const result = formatChangesets([]);
+		expect(result).toBe("");
+	});
+});