🧪 Add unit tests for dep-versions utility

🎯 What: Add unit tests to cover the functionality of the `depVersions` module which dynamically computes and resolves the version of dependencies based on the `package.json` file in the current working directory.
📊 Coverage: Added scenarios for handling a missing `package.json`, a `package.json` with no dependencies, successful versions resolutions with alphabetical sorting, skipping of non-resolvable modules without crashing, and deduplication of packages appearing in both `dependencies` and `devDependencies`.
✨ Result: `src/utils/dep-versions.ts` is now covered effectively by using temporary isolated filesystem setups and bypassing module caching, improving overall reliability.

Co-authored-by: sunnylqm <615282+sunnylqm@users.noreply.github.com>

Author: google-labs-jules[bot]

tests/dep-versions.test.ts

@@ -0,0 +1,140 @@
+import { afterEach, beforeEach, describe, expect, test } from 'bun:test';
+import * as fs from 'fs';
+import * as os from 'os';
+import * as path from 'path';
+
+describe('depVersions utility', () => {
+  const originalCwd = process.cwd();
+  let testDir: string;
+  let testCount = 0;
+
+  beforeEach(() => {
+    testCount++;
+    testDir = path.join(os.tmpdir(), `temp-test-dep-versions-${Date.now()}-${testCount}`);
+    fs.mkdirSync(testDir, { recursive: true });
+    process.chdir(testDir);
+  });
+
+  afterEach(() => {
+    process.chdir(originalCwd);
+    fs.rmSync(testDir, { recursive: true, force: true });
+  });
+
+  const loadDepVersions = async () => {
+    // Bust the module cache by appending a query string
+    // Since the process.cwd() has changed, we need the absolute path to the module
+    const modulePath = path.join(originalCwd, 'src', 'utils', 'dep-versions.ts');
+    const module = await import(`${modulePath}?t=${Date.now()}_${testCount}`);
+    return module.depVersions;
+  };
+
+  test('should return an empty object if no package.json is found', async () => {
+    // testDir has no package.json
+    const deps = await loadDepVersions();
+    expect(deps).toEqual({});
+  });
+
+  test('should return an empty object if package.json has no dependencies or devDependencies', async () => {
+    fs.writeFileSync(
+      path.join(testDir, 'package.json'),
+      JSON.stringify({ name: 'test-app' }),
+    );
+
+    const deps = await loadDepVersions();
+    expect(deps).toEqual({});
+  });
+
+  test('should resolve versions for dependencies and devDependencies and sort keys', async () => {
+    fs.writeFileSync(
+      path.join(testDir, 'package.json'),
+      JSON.stringify({
+        dependencies: {
+          zeta: '^1.0.0',
+          alpha: '^2.0.0',
+        },
+        devDependencies: {
+          beta: '^3.0.0',
+        },
+      }),
+    );
+
+    const depsToCreate = [
+      { name: 'zeta', version: '1.0.5' },
+      { name: 'alpha', version: '2.1.0' },
+      { name: 'beta', version: '3.0.1' },
+    ];
+
+    for (const dep of depsToCreate) {
+      const depDir = path.join(testDir, 'node_modules', dep.name);
+      fs.mkdirSync(depDir, { recursive: true });
+      fs.writeFileSync(
+        path.join(depDir, 'package.json'),
+        JSON.stringify({ version: dep.version }),
+      );
+    }
+
+    const deps = await loadDepVersions();
+
+    // Check that versions are resolved
+    expect(deps).toEqual({
+      alpha: '2.1.0',
+      beta: '3.0.1',
+      zeta: '1.0.5',
+    });
+
+    // Check that keys are sorted alphabetically
+    const keys = Object.keys(deps);
+    expect(keys).toEqual(['alpha', 'beta', 'zeta']);
+  });
+
+  test('should skip dependencies that cannot be resolved without throwing an error', async () => {
+    fs.writeFileSync(
+      path.join(testDir, 'package.json'),
+      JSON.stringify({
+        dependencies: {
+          exists: '^1.0.0',
+          missing: '^2.0.0',
+        },
+      }),
+    );
+
+    // Only create 'exists'
+    const existsDir = path.join(testDir, 'node_modules', 'exists');
+    fs.mkdirSync(existsDir, { recursive: true });
+    fs.writeFileSync(
+      path.join(existsDir, 'package.json'),
+      JSON.stringify({ version: '1.0.0' }),
+    );
+
+    const deps = await loadDepVersions();
+    expect(deps).toEqual({
+      exists: '1.0.0',
+    });
+  });
+
+  test('should deduplicate dependencies appearing in both dependencies and devDependencies', async () => {
+    fs.writeFileSync(
+      path.join(testDir, 'package.json'),
+      JSON.stringify({
+        dependencies: {
+          shared: '^1.0.0',
+        },
+        devDependencies: {
+          shared: '^1.0.0',
+        },
+      }),
+    );
+
+    const sharedDir = path.join(testDir, 'node_modules', 'shared');
+    fs.mkdirSync(sharedDir, { recursive: true });
+    fs.writeFileSync(
+      path.join(sharedDir, 'package.json'),
+      JSON.stringify({ version: '1.0.2' }),
+    );
+
+    const deps = await loadDepVersions();
+    expect(deps).toEqual({
+      shared: '1.0.2',
+    });
+  });
+});