Enhance sorting of installable files to prioritize shallower paths in getProjectInstallable function

Author: eleanorjboyd

src/managers/builtin/pipUtils.ts

@@ -295,7 +295,16 @@ export async function getProjectInstallable(
                     const p = api.getPythonProject(uri)?.uri.fsPath;
                     return p && fsPaths.includes(p);
                 })
-                .sort();
+                .sort((a, b) => {
+                    // Sort by path depth (shallowest first) so top-level files like
+                    // requirements.txt appear before deeply nested ones.
+                    const depthA = a.fsPath.split(path.sep).length;
+                    const depthB = b.fsPath.split(path.sep).length;
+                    if (depthA !== depthB) {
+                        return depthA - depthB;
+                    }
+                    return a.fsPath.localeCompare(b.fsPath);
+                });
 
             await Promise.all(
                 filtered.map(async (uri) => {

src/test/managers/builtin/pipUtils.unit.test.ts

@@ -199,4 +199,36 @@ suite('Pip Utils - getProjectInstallable', () => {
         assert.ok(firstResult.uri, 'Should have a URI');
         assert.ok(firstResult.uri.fsPath.startsWith(workspacePath), 'Should be in workspace directory');
     });
+
+    test('should sort shallower files before deeper ones', async () => {
+        // Arrange: Return files at different depths, with deeper ones discovered first
+        findFilesStub.callsFake((pattern: string) => {
+            const workspacePath = Uri.file('/test/path/root').fsPath;
+            if (pattern === '**/*requirements*.txt') {
+                return Promise.resolve([
+                    Uri.file(path.join(workspacePath, 'deep', 'nested', 'sub', 'requirements.txt')),
+                    Uri.file(path.join(workspacePath, 'subdir', 'dev-requirements.txt')),
+                ]);
+            } else if (pattern === '*requirements*.txt') {
+                return Promise.resolve([Uri.file(path.join(workspacePath, 'requirements.txt'))]);
+            } else if (pattern === '**/requirements/*.txt') {
+                return Promise.resolve([]);
+            } else if (pattern === '**/pyproject.toml') {
+                return Promise.resolve([]);
+            }
+            return Promise.resolve([]);
+        });
+
+        // Act
+        const workspacePath = Uri.file('/test/path/root').fsPath;
+        const projects = [{ name: 'workspace', uri: Uri.file(workspacePath) }];
+        const result = (await getProjectInstallable(mockApi as PythonEnvironmentApi, projects)).installables;
+
+        // Assert: root-level requirements.txt should come first
+        assert.strictEqual(result.length, 3);
+        const names = result.map((r) => r.name);
+        assert.strictEqual(names[0], 'requirements.txt', 'Root-level requirements.txt should be first');
+        assert.strictEqual(names[1], 'dev-requirements.txt', 'One-level-deep file should be second');
+        assert.strictEqual(names[2], 'requirements.txt', 'Deeply nested file should be last');
+    });
 });