cli-node: refactor git into GitUtils

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

packages/cli-node/src/git/GitUtils.test.ts

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-import { runGit, listChangedFiles } from './git';
+import { runGit, GitUtils } from './GitUtils';
 
 describe('runGit', () => {
   it('runs a git command', async () => {
@@ -43,10 +43,14 @@ describe('runGit', () => {
 
 describe('listChangedFiles', () => {
   it('requires a ref', async () => {
-    await expect(listChangedFiles('')).rejects.toThrow('ref is required');
+    await expect(GitUtils.listChangedFiles('')).rejects.toThrow(
+      'ref is required',
+    );
   });
 
   it('should return something', async () => {
-    await expect(listChangedFiles('HEAD')).resolves.toEqual(expect.any(Array));
+    await expect(GitUtils.listChangedFiles('HEAD')).resolves.toEqual(
+      expect.any(Array),
+    );
   });
 });

packages/cli-node/src/git/GitUtils.ts

@@ -15,11 +15,8 @@
  */
 
 import { assertError, ForwardedError } from '@backstage/errors';
-import { execFile as execFileCb } from 'child_process';
-import { promisify } from 'util';
 import { paths } from '../paths';
-
-const execFile = promisify(execFileCb);
+import { execFile } from '../run';
 
 /**
  * Run a git command, trimming the output splitting it into lines.
@@ -43,44 +40,55 @@ export async function runGit(...args: string[]) {
 }
 
 /**
- * Returns a sorted list of all files that have changed since the merge base
- * of the provided `ref` and HEAD, as well as all files that are not tracked by git.
+ * Utilities for working with git.
+ *
+ * @public
  */
-export async function listChangedFiles(ref: string) {
-  if (!ref) {
-    throw new Error('ref is required');
+export class GitUtils {
+  /**
+   * Returns a sorted list of all files that have changed since the merge base
+   * of the provided `ref` and HEAD, as well as all files that are not tracked by git.
+   */
+  static async listChangedFiles(ref: string) {
+    if (!ref) {
+      throw new Error('ref is required');
+    }
+
+    let diffRef = ref;
+    try {
+      const [base] = await runGit('merge-base', 'HEAD', ref);
+      diffRef = base;
+    } catch {
+      // silently fall back to using the ref directly if merge base is not available
+    }
+
+    const tracked = await runGit('diff', '--name-only', diffRef);
+    const untracked = await runGit(
+      'ls-files',
+      '--others',
+      '--exclude-standard',
+    );
+
+    return Array.from(new Set([...tracked, ...untracked]));
   }
 
-  let diffRef = ref;
-  try {
-    const [base] = await runGit('merge-base', 'HEAD', ref);
-    diffRef = base;
-  } catch {
-    // silently fall back to using the ref directly if merge base is not available
+  /**
+   * Returns the contents of a file at a specific ref.
+   */
+  static async readFileAtRef(path: string, ref: string) {
+    let showRef = ref;
+    try {
+      const [base] = await runGit('merge-base', 'HEAD', ref);
+      showRef = base;
+    } catch {
+      // silently fall back to using the ref directly if merge base is not available
+    }
+
+    const { stdout } = await execFile('git', ['show', `${showRef}:${path}`], {
+      shell: true,
+      cwd: paths.targetRoot,
+      maxBuffer: 1024 * 1024 * 50,
+    });
+    return stdout;
   }
-
-  const tracked = await runGit('diff', '--name-only', diffRef);
-  const untracked = await runGit('ls-files', '--others', '--exclude-standard');
-
-  return Array.from(new Set([...tracked, ...untracked]));
-}
-
-/**
- * Returns the contents of a file at a specific ref.
- */
-export async function readFileAtRef(path: string, ref: string) {
-  let showRef = ref;
-  try {
-    const [base] = await runGit('merge-base', 'HEAD', ref);
-    showRef = base;
-  } catch {
-    // silently fall back to using the ref directly if merge base is not available
-  }
-
-  const { stdout } = await execFile('git', ['show', `${showRef}:${path}`], {
-    shell: true,
-    cwd: paths.targetRoot,
-    maxBuffer: 1024 * 1024 * 50,
-  });
-  return stdout;
 }

packages/cli-node/src/git/index.ts

@@ -14,4 +14,4 @@
  * limitations under the License.
  */
 
-export { listChangedFiles, readFileAtRef } from './git';
+export { GitUtils } from './GitUtils';

packages/cli-node/src/index.ts

@@ -19,3 +19,5 @@
  *
  * @packageDocumentation
  */
+
+export * from './git';

packages/cli-node/src/monorepo/PackageGraph.test.ts

@@ -18,16 +18,10 @@ import { resolve as resolvePath } from 'path';
 import { getPackages } from '@manypkg/get-packages';
 import { PackageGraph } from './PackageGraph';
 import { Lockfile } from './Lockfile';
-import { listChangedFiles, readFileAtRef } from '../git';
+import { GitUtils } from '../git';
 
-jest.mock('../git');
-
-const mockListChangedFiles = listChangedFiles as jest.MockedFunction<
-  typeof listChangedFiles
->;
-const mockReadFileAtRef = readFileAtRef as jest.MockedFunction<
-  typeof readFileAtRef
->;
+const mockListChangedFiles = jest.spyOn(GitUtils, 'listChangedFiles');
+const mockReadFileAtRef = jest.spyOn(GitUtils, 'readFileAtRef');
 
 jest.mock('../paths', () => ({
   paths: {

packages/cli-node/src/monorepo/PackageGraph.ts

@@ -18,7 +18,7 @@ import path from 'path';
 import { getPackages, Package } from '@manypkg/get-packages';
 import { paths } from '../paths';
 import { PackageRole } from '../role';
-import { listChangedFiles, readFileAtRef } from '../git';
+import { GitUtils } from '../git';
 import { Lockfile } from './Lockfile';
 import { JsonValue } from '@backstage/types';
 
@@ -214,7 +214,7 @@ export class PackageGraph extends Map<string, PackageGraphNode> {
     ref: string;
     analyzeLockfile?: boolean;
   }) {
-    const changedFiles = await listChangedFiles(options.ref);
+    const changedFiles = await GitUtils.listChangedFiles(options.ref);
 
     const dirMap = new Map(
       Array.from(this.values()).map(pkg => [
@@ -265,7 +265,7 @@ export class PackageGraph extends Map<string, PackageGraphNode> {
           paths.resolveTargetRoot('yarn.lock'),
         );
         otherLockfile = Lockfile.parse(
-          await readFileAtRef('yarn.lock', options.ref),
+          await GitUtils.readFileAtRef('yarn.lock', options.ref),
         );
       } catch (error) {
         console.warn(