Add support for Projects in Testing #25780

eleanorjboyd · 2026-02-09T21:04:38Z

fixes microsoft/vscode-python-environments#987

## Summary This PR implements **project-based test discovery** for pytest, enabling multi-project workspace support. When the Python Environments API is available, the extension now discovers Python projects within workspaces and creates separate test tree roots for each project with its own Python environment. ## What's New ### Project-Based Testing Architecture - **TestProjectRegistry**: Manages the lifecycle of Python test projects, including: - Discovering projects via Python Environments API - Creating ProjectAdapter instances per workspace - Computing nested project relationships for ignore lists - Fallback to "legacy" single-adapter mode when API unavailable - **ProjectAdapter**: Interface representing a single Python project with test infrastructure: - Project identity (ID, name, URI) - Python environment from the environments API - Test framework adapters (discovery/execution) - Nested project ignore paths ### Key Features - ✅ **Multi-project workspaces**: Each Python project gets its own test tree root - ✅ **Nested project handling**: Parent projects automatically ignore nested child projects via `--ignore` flags - ✅ **Graceful fallback**: Falls back to legacy single-adapter mode if Python Environments API is unavailable - ✅ **Project root path**: Python-side `get_test_root_path()` function returns appropriate root for test tree ### Code Improvements - Standardized logging prefixes to `[test-by-project]` across all files - Centralized adapter creation via `createTestAdapters()` helper method - Extracted reusable methods for discovery, execution, and file watching ## Scope & Limitations > **⚠️ Important: unittest is NOT supported in this PR** > > This PR focuses exclusively on **pytest**. unittest support for project-based testing will be implemented in a future PR. ## Testing - Added unit tests for `TestProjectRegistry` class - Added unit tests for Python-side `get_test_root_path()` function - Manual testing with multi-project workspaces ## Related Issues first step in: microsoft/vscode-python-environments#987 --------- Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

This adds a place within the github workspace that developers can store any AI related artifacts they create that could be useful but they don't want to commit. Things like issue summarization, plans for features, code analysis etc

Copilot

Pull request overview

This PR adds project-based (multi-project) testing support to the VS Code Python extension’s Test Explorer integration, leveraging the Python Environments API so each project can be discovered/run/debugged with its own environment (fixes microsoft/vscode-python-environments#987).

Changes:

Introduces a project registry + project adapter model to discover/register multiple Python projects per workspace and run discovery/execution per project.
Scopes VS Code test IDs by project (via a project ID separator) and threads project context through discovery/execution adapters (including PROJECT_ROOT_PATH support in Python runner scripts).
Adds extensive unit tests (TS + Python) covering project-based discovery/execution, nested project behavior, and debug session handling.

Reviewed changes

Copilot reviewed 36 out of 36 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/client/testing/testController/controller.ts	Adds project-based activation/discovery/execution flow and project-change handling.
src/client/testing/testController/common/testProjectRegistry.ts	New registry for discovering projects, creating project-specific adapters/resolvers, and nested ignore computation.
src/client/testing/testController/common/projectAdapter.ts	Defines per-project adapter shape (env + adapters + resolver + lifecycle).
src/client/testing/testController/common/projectUtils.ts	Adds project ID scoping utilities + shared adapter creation helper.
src/client/testing/testController/common/projectTestExecution.ts	Executes selected tests grouped by owning project with project-specific environment/debug/coverage behavior.
src/client/testing/testController/common/utils.ts	Adds project-scoped IDs in `populateTestTree()` and project-aware error labels.
src/client/testing/testController/common/testDiscoveryHandler.ts	Routes discovery into project-scoped IDs and project-scoped error nodes.
src/client/testing/testController/pytest/pytestDiscoveryAdapter.ts	Threads `ProjectAdapter` through discovery; adds nested `--ignore` support; sets `PROJECT_ROOT_PATH`.
src/client/testing/testController/pytest/pytestExecutionAdapter.ts	Threads `ProjectAdapter` through execution; uses project env when available; sets `PROJECT_ROOT_PATH`.
src/client/testing/testController/unittest/testDiscoveryAdapter.ts	Threads `ProjectAdapter` through discovery; uses project env when available; sets `PROJECT_ROOT_PATH`.
src/client/testing/testController/unittest/testExecutionAdapter.ts	Threads `ProjectAdapter` through execution/debug; uses project env when available; sets `PROJECT_ROOT_PATH`.
src/client/testing/testController/workspaceTestAdapter.ts	Allows passing a `ProjectAdapter` to execution for project-scoped runs.
src/client/testing/common/debugLauncher.ts	Adds multi-session tracking via markers; supports project-based debug naming + Python path resolution.
python_files/vscode_pytest/init.py	Uses `PROJECT_ROOT_PATH` to root discovery/execution payload cwd/test-tree root for project mode.
python_files/unittestadapter/discovery.py	Supports `PROJECT_ROOT_PATH` to override cwd/top-level behavior for project-rooted discovery.
python_files/unittestadapter/execution.py	Supports `PROJECT_ROOT_PATH` to override cwd in execution payloads.
src/test/vscode-mock.ts	Adds `vscode.tests.createTestController()` mock for unit tests.
src/test/testing/testController/**	Adds unit tests for project registry, project execution grouping, controller behavior, adapters, and utilities.
python_files/tests/**	Adds Python-side tests for `PROJECT_ROOT_PATH` behavior for both unittest + pytest.
.github/instructions/testing_feature_area.instructions.md	Documents the new project-based testing architecture and key files/tests.

src/client/testing/common/debugLauncher.ts

src/client/testing/testController/common/testProjectRegistry.ts

src/client/testing/testController/controller.ts

Copilot

Pull request overview

Copilot reviewed 36 out of 36 changed files in this pull request and generated 3 comments.

Copilot · 2026-02-10T03:48:23Z

src/client/testing/testController/common/utils.ts

                let node = testController.items.get(child.path);

                if (!node) {
-                    node = testController.createTestItem(child.id_, child.name, Uri.file(child.path));
+                    // Create project-scoped ID for non-test nodes
+                    const nodeId = projectId ? `${projectId}${PROJECT_ID_SEPARATOR}${child.id_}` : child.id_;
+                    node = testController.createTestItem(nodeId, child.name, Uri.file(child.path));


In project-scoped mode, folder/non-test nodes are looked up via testController.items.get(child.path), but they are created with an ID that includes the project scope (${projectId}${PROJECT_ID_SEPARATOR}...). This lookup will never find existing nodes (and can also accidentally pick up an unrelated root item whose ID happens to equal child.path in multi-root/nested workspaces). Prefer looking up by the same scoped ID you create (and ideally against testRoot.children, not the global testController.items) before deciding to create a new node.

See below for a potential fix:

// Use project-scoped ID for non-test nodes and look up within the current root const nodeId = projectId ? `${projectId}${PROJECT_ID_SEPARATOR}${child.id_}` : child.id_; let node = testRoot!.children.get(nodeId); if (!node) {

Copilot · 2026-02-10T03:48:24Z

src/client/testing/testController/common/testProjectRegistry.ts

+            testProvider,
+            workspaceUri,
+            projectId,
+            pythonProject.name, // Use simple project name for test tree label (without version)


ProjectAdapter.projectName is computed as a display name including the Python version (createProjectDisplayName(...)), but PythonResultResolver is initialized with pythonProject.name (without version). This makes the Test Explorer root label / discovery error labels / debug session naming (via project.pythonProject) inconsistent with the adapter’s display name and can make it hard to distinguish projects that share a name but differ by interpreter. Consider passing the computed projectDisplayName into PythonResultResolver (and/or using it when building the LaunchOptions.project object) so UI labels are consistent and disambiguated.

Suggested change

pythonProject.name, // Use simple project name for test tree label (without version)

projectDisplayName, // Use display name (including version) for test tree label

Copilot · 2026-02-10T03:48:24Z

src/client/testing/testController/controller.ts

+            // Track completion for progress logging
+            const projectsCompleted = new Set<string>();
+
+            // Run discovery for all projects in parallel
+            await Promise.all(projects.map((project) => this.discoverTestsForProject(project, projectsCompleted)));
+
+            traceInfo(
+                `[test-by-project] Discovery complete: ${projectsCompleted.size}/${projects.length} projects succeeded`,
+            );


projectsCompleted is incremented for both successful and failed project discoveries (see catch block in discoverTestsForProject()), but the summary log says "projects succeeded". This makes the completion log inaccurate; either track successes separately or change the message to reflect "completed"/"attempted" rather than "succeeded".

eleanorjboyd and others added 6 commits February 5, 2026 21:37

Thick-puffin (#25768)

2d53b1f

Unittest discovery with py-env Projects Support (#25767)

5104ff6

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

fix bug with double error nodes

42fb7b7

Add python-environment's project support for pytest execution (#25772)

3b87651

eleanorjboyd added the feature-request Request for new features or functionality label Feb 9, 2026

eleanorjboyd self-assigned this Feb 9, 2026

eleanorjboyd added 2 commits February 9, 2026 13:48

Python Environments Project Support for Unittest Execution (#25779)

f048ef4

Merge branch 'main' into test-project-support

0cfd96d

eleanorjboyd requested a review from Copilot February 9, 2026 21:54

eleanorjboyd marked this pull request as ready for review February 9, 2026 21:54

eleanorjboyd requested review from anthonykim1 and karthiknadig February 9, 2026 21:54

Copilot started reviewing on behalf of eleanorjboyd February 9, 2026 21:55 View session

vs-code-engineering bot added this to the February 2026 milestone Feb 9, 2026

Copilot AI reviewed Feb 9, 2026

View reviewed changes

src/client/testing/common/debugLauncher.ts Outdated Show resolved Hide resolved

src/client/testing/testController/common/testProjectRegistry.ts Outdated Show resolved Hide resolved

src/client/testing/testController/controller.ts Outdated Show resolved Hide resolved

eleanorjboyd added 2 commits February 9, 2026 18:54

based on copilot comments

c1f7fb1

test fix

bd2aadb

eleanorjboyd requested a review from Copilot February 10, 2026 03:43

Copilot started reviewing on behalf of eleanorjboyd February 10, 2026 03:43 View session

Copilot AI reviewed Feb 10, 2026

View reviewed changes

updates

275fbb6

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Add support for Projects in Testing #25780

Add support for Projects in Testing #25780

Uh oh!

eleanorjboyd commented Feb 9, 2026 •

edited

Loading

Uh oh!

Copilot AI left a comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Copilot AI left a comment

Uh oh!

Copilot AI Feb 10, 2026

Uh oh!

Copilot AI Feb 10, 2026

Uh oh!

Copilot AI Feb 10, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

1 participant

	pythonProject.name, // Use simple project name for test tree label (without version)
	projectDisplayName, // Use display name (including version) for test tree label

Add support for Projects in Testing #25780

Are you sure you want to change the base?

Add support for Projects in Testing #25780

Uh oh!

Conversation

eleanorjboyd commented Feb 9, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Reviewed changes

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Uh oh!

Copilot AI Feb 10, 2026

Choose a reason for hiding this comment

Uh oh!

Copilot AI Feb 10, 2026

Choose a reason for hiding this comment

Uh oh!

Copilot AI Feb 10, 2026

Choose a reason for hiding this comment

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

1 participant

eleanorjboyd commented Feb 9, 2026 •

edited

Loading