From aeef68fc3690c1958466fdbfe5dbef33b93e866e Mon Sep 17 00:00:00 2001
From: "Michael B. Gale" <mbg@github.com>
Date: Fri, 24 Jul 2026 15:23:11 +0100
Subject: [PATCH] Add `bundle-changelog.ts` with tests

---
 pr-checks/bundle-changelog.test.ts | 142 +++++++++++++++++++++++++++++
 pr-checks/bundle-changelog.ts      | 124 +++++++++++++++++++++++++
 pr-checks/config.ts                |   4 +
 3 files changed, 270 insertions(+)
 create mode 100644 pr-checks/bundle-changelog.test.ts
 create mode 100755 pr-checks/bundle-changelog.ts

diff --git a/pr-checks/bundle-changelog.test.ts b/pr-checks/bundle-changelog.test.ts
new file mode 100644
index 000000000..6cc4d096b
--- /dev/null
+++ b/pr-checks/bundle-changelog.test.ts
@@ -0,0 +1,142 @@
+/**
+ * Tests for `bundle-changelog.ts`.
+ */
+
+import * as assert from "node:assert/strict";
+import * as fs from "node:fs";
+import * as os from "node:os";
+import * as path from "node:path";
+import { afterEach, beforeEach, describe, it } from "node:test";
+
+import {
+  CLI_VERSION_ENV_VAR,
+  getCLIVersion,
+  getPRNumber,
+  getPRUrl,
+  PR_URL_ENV_VAR,
+  updateChangelog,
+} from "./bundle-changelog";
+import {
+  EMPTY_CHANGELOG,
+  NO_CHANGES_STR,
+  UNRELEASED_PLACEHOLDER,
+} from "./changelog";
+
+let testDir: string;
+
+beforeEach(() => {
+  // Set up a temporary directory for testing
+  testDir = fs.mkdtempSync(path.join(os.tmpdir(), "bundle-changelog-test-"));
+});
+
+afterEach(() => {
+  /** Clean up temporary directories. */
+  fs.rmSync(testDir, { recursive: true, force: true });
+});
+
+describe("getCLIVersion", async () => {
+  await it("throws if the environment variable is not set", async () => {
+    delete process.env[CLI_VERSION_ENV_VAR];
+    assert.throws(() => getCLIVersion());
+  });
+
+  await it("throws if the environment variable is empty", async () => {
+    process.env[CLI_VERSION_ENV_VAR] = "    ";
+    assert.throws(() => getCLIVersion());
+  });
+
+  await it("returns value of the environment variable if set", async () => {
+    const testValue = "1.2.3";
+    process.env[CLI_VERSION_ENV_VAR] = testValue;
+    assert.deepEqual(getCLIVersion(), testValue);
+  });
+});
+
+const testPrUrl = "https://github.com/github/codeql-action/pulls/42";
+
+describe("getPRUrl", async () => {
+  await it("throws if the environment variable is not set", async () => {
+    delete process.env[PR_URL_ENV_VAR];
+    assert.throws(() => getPRUrl());
+  });
+
+  await it("throws if the environment variable is empty", async () => {
+    process.env[PR_URL_ENV_VAR] = "    ";
+    assert.throws(() => getPRUrl());
+  });
+
+  await it("returns value of the environment variable if set", async () => {
+    process.env[PR_URL_ENV_VAR] = testPrUrl;
+    assert.deepEqual(getPRUrl(), testPrUrl);
+  });
+});
+
+describe("getPRNumber", async () => {
+  await it("throws if the last part of the input is not a number", async () => {
+    assert.throws(() => getPRNumber(`${testPrUrl}/foo`));
+  });
+
+  await it("throws if the last part of the input is not a positive number", async () => {
+    assert.throws(() => getPRNumber(`${testPrUrl}/-100`));
+  });
+
+  await it("returns the PR number from an URL", async () => {
+    assert.equal(getPRNumber(testPrUrl), 42);
+  });
+});
+
+const testChangelog = `${EMPTY_CHANGELOG.trimEnd()}
+
+## 4.23.7
+
+- Other change
+
+## 4.23.6
+
+${NO_CHANGES_STR}`;
+
+const expectedChangelog = `# CodeQL Action Changelog
+
+## ${UNRELEASED_PLACEHOLDER}
+
+- Update default CodeQL bundle version to
+
+## 4.23.7
+
+- Other change
+
+## 4.23.6
+
+${NO_CHANGES_STR}`;
+
+describe("updateChangelog", async () => {
+  await it("removes `NO_CHANGES_STR` if present in [UNRELEASED] section", async () => {
+    const result = updateChangelog(EMPTY_CHANGELOG, "");
+    assert.ok(!result.includes(NO_CHANGES_STR.trim()));
+  });
+
+  await it("doesn't remove `NO_CHANGES_STR` if present in versioned section", async () => {
+    const result = updateChangelog(
+      EMPTY_CHANGELOG.replace(UNRELEASED_PLACEHOLDER, "1.2.3"),
+      "",
+    );
+    assert.ok(result.includes(NO_CHANGES_STR.trim()));
+  });
+
+  await it("throws if there are no sections", async () => {
+    assert.throws(() => {
+      updateChangelog(
+        "# CodeQL Action Changelog",
+        "- Update default CodeQL bundle version to",
+      );
+    });
+  });
+
+  await it("adds note at the end of the first section", async () => {
+    const result = updateChangelog(
+      testChangelog,
+      "- Update default CodeQL bundle version to",
+    );
+    assert.deepEqual(result, expectedChangelog);
+  });
+});
diff --git a/pr-checks/bundle-changelog.ts b/pr-checks/bundle-changelog.ts
new file mode 100755
index 000000000..ffe360be6
--- /dev/null
+++ b/pr-checks/bundle-changelog.ts
@@ -0,0 +1,124 @@
+#!/usr/bin/env npx tsx
+
+/**
+ * Updates the changelog with a change note for an updated CodeQL CLI bundle.
+ */
+
+import * as fs from "node:fs";
+
+import { getErrorMessage } from "../src/util";
+
+import { CHANGELOG_FILE, CLI_BUNDLE_RELEASE_URL_PREFIX } from "./config";
+import { NO_CHANGES_STR, parseChangelog, renderChangelog, UNRELEASED_PLACEHOLDER } from "./changelog";
+
+export const CLI_VERSION_ENV_VAR = "CLI_VERSION";
+export const PR_URL_ENV_VAR = "PR_URL";
+
+/** Gets the CLI version from the environment. */
+export function getCLIVersion() {
+  const cliVersion = process.env[CLI_VERSION_ENV_VAR];
+
+  if (cliVersion === undefined || cliVersion.trim() === "") {
+    throw new Error(`No CLI version was set in '${CLI_VERSION_ENV_VAR}'.`);
+  }
+
+  return cliVersion;
+}
+
+/** Gets the PR URL from the environment. */
+export function getPRUrl() {
+  const prUrl = process.env[PR_URL_ENV_VAR];
+
+  if (prUrl === undefined || prUrl.trim() === "") {
+    throw new Error(`No PR URL was set in '${PR_URL_ENV_VAR}'.`);
+  }
+
+  return prUrl;
+}
+
+/**
+ * Gets the PR number from something like a PR URL.
+ */
+export function getPRNumber(prUrl: string) {
+  const prUrlParts = prUrl.split("/");
+  const prNumberStr = prUrlParts[prUrlParts.length - 1];
+
+  const prNumber = Number.parseInt(prNumberStr, 10);
+
+  if (!Number.isInteger(prNumber) || prNumber <= 0) {
+    throw new Error(
+      `Invalid PR URL '${prUrl}': last part is not a positive number`,
+    );
+  }
+
+  return prNumber;
+}
+
+/**
+ * Updates `changelog` by adding `changelogNote` to the first section.
+ *
+ * @param contents The existing changelog contents.
+ * @param changelogNote The note to add to the first section.
+ */
+export function updateChangelog(contents: string, changelogNote: string) {
+  // If the "[UNRELEASED]" section starts with "no user facing changes", remove that line.
+  contents = contents.replace(
+    `## ${UNRELEASED_PLACEHOLDER}\n\nNo user facing changes.`,
+    `## ${UNRELEASED_PLACEHOLDER}\n`,
+  );
+
+  const changelog = parseChangelog(contents);
+
+  if (changelog.sections.length === 0) {
+    throw new Error("The changelog contains no existing sections.");
+  }
+
+  // Add the changelog note to the bottom of the first section.
+  const firstSection = changelog.sections[0];
+  const lastLine = firstSection.bodyLines.pop();
+
+  if (lastLine !== undefined && lastLine.trim() != "") {
+    // We expect the last line to be empty. If it isn't for some reason,
+    // add it back.
+    firstSection.bodyLines.push(lastLine);
+  }
+
+  firstSection.bodyLines.push(changelogNote);
+
+  // If the last line is empty as expected, then add it back in after the new note.
+  if (lastLine !== undefined && lastLine.trim() == "") {
+    firstSection.bodyLines.push(lastLine);
+  }
+
+  return renderChangelog(changelog);
+}
+
+function main() {
+  try {
+    const cliVersion = getCLIVersion();
+    const prUrl = getPRUrl();
+
+    // The GitHub Release for the new bundle version.
+    const bundleReleaseUrl = `${CLI_BUNDLE_RELEASE_URL_PREFIX}${cliVersion}`;
+
+    // Get the PR number from the PR URL.
+    const prNumber = getPRNumber(prUrl);
+    const changelogNote = `- Update default CodeQL bundle version to [${cliVersion}](${bundleReleaseUrl}). [#${prNumber}](${prUrl})`;
+
+    let changelog = fs.readFileSync(CHANGELOG_FILE, "utf-8");
+
+    changelog = updateChangelog(changelog, changelogNote);
+
+    fs.writeFileSync(CHANGELOG_FILE, changelog);
+
+    return 0;
+  } catch (err) {
+    console.error(`Failed to bundle changelog: ${getErrorMessage(err)}`);
+    return -1;
+  }
+}
+
+// Only call `main` if this script was run directly.
+if (require.main === module) {
+  process.exit(main());
+}
diff --git a/pr-checks/config.ts b/pr-checks/config.ts
index 94d34a931..356fe665f 100644
--- a/pr-checks/config.ts
+++ b/pr-checks/config.ts
@@ -37,6 +37,10 @@ export const API_COMPATIBILITY_FILE = path.join(
   "api-compatibility.json",
 );
 
+/** The prefix of CodeQL CLI bundle release URLs. */
+export const CLI_BUNDLE_RELEASE_URL_PREFIX =
+  "https://github.com/github/codeql-action/releases/tag/codeql-bundle-v";
+
 /** A common interface for operations that support dry runs. */
 export interface DryRunOption {
   /** A value indicating whether to perform operations with side effects. */