Make coverage opt-in instead of running on every pytest

.github/workflows/libero-e2e.yaml

@@ -41,7 +41,7 @@ jobs:
       - name: Replay a LIBERO demo through the env server (software rendering)
         env:
           MUJOCO_GL: osmesa
-        run: uv run pytest positronic/simulator/libero/tests/test_e2e.py --no-cov -rs
+        run: uv run pytest positronic/simulator/libero/tests/test_e2e.py -rs
 
       # Reuses the LIBERO checkout the replay above cloned (``~/.cache/positronic/libero/src``). Validates the
       # command transform (FK/IK + each controller's set_goal inverse) and the gripper normalization against

.github/workflows/unit-test.yaml

@@ -31,21 +31,10 @@ jobs:
       - name: Install dependencies
         run: uv sync --locked
 
-      - name: "Run tests (coverage: term, html)"
+      - name: Run tests
         env:
           PYTHONPATH: ${{ env.PYTHONPATH }}:$PWD
-        run: uv run pytest --cov-report=html
-
-      - name: Coverage summary (job summary)
-        if: always()
-        run: uv run coverage report -m >> $GITHUB_STEP_SUMMARY
-
-      - name: Upload coverage HTML artifact
-        if: always()
-        uses: actions/upload-artifact@v4
-        with:
-          name: coverage-html-core-${{ matrix.os }}-${{ matrix.python }}
-          path: htmlcov
+        run: uv run pytest
 
   packaging:
     runs-on: ubuntu-latest
@@ -81,7 +70,7 @@ jobs:
       - name: Run lerobot vendor tests
         env:
           PYTHONPATH: ${{ env.PYTHONPATH }}:$PWD
-        run: uv run pytest positronic/vendors/lerobot_0_3_3/tests --no-cov
+        run: uv run pytest positronic/vendors/lerobot_0_3_3/tests
 
   lerobot-latest:
     runs-on: ubuntu-latest
@@ -101,7 +90,7 @@ jobs:
       - name: Run lerobot vendor tests
         env:
           PYTHONPATH: ${{ env.PYTHONPATH }}:$PWD
-        run: uv run pytest positronic/vendors/lerobot/tests --no-cov
+        run: uv run pytest positronic/vendors/lerobot/tests
 
   lockfile-portability:
     strategy:

CLAUDE.md

@@ -15,8 +15,8 @@
 
 # Commands
 - Every Python execution goes through `uv run --locked` — bare `python`/`pytest` bypasses the locked venv
-- Run tests: `uv run --locked pytest --no-cov`
-- Run single test file: `uv run --locked pytest path/to/test_file.py --no-cov`
+- Run tests: `uv run --locked pytest`
+- Run single test file: `uv run --locked pytest path/to/test_file.py`
 - Lint: `uv run --locked ruff check --fix .`
 - Format: `uv run --locked ruff format .`
 - Run any Python: `uv run --locked python script.py`

README.md

@@ -321,7 +321,7 @@ repoints it at the tool.
 Run tests and linters from the root directory:
 
 ```bash
-uv run --locked pytest --no-cov
+uv run --locked pytest
 uv run --locked ruff check .
 uv run --locked ruff format .
 ```

docs/CONTRIBUTING.md

@@ -151,7 +151,7 @@ uv run pytest
 With coverage report:
 
 ```bash
-uv run pytest --cov=positronic --cov=pimm --cov-report=term-missing
+uv run pytest --cov --cov-report=term-missing
 ```
 
 ## Pull Request Guidelines

pimm/tests/test_world.py

@@ -228,6 +228,20 @@ def test_world_defaults_to_system_clock(self):
             assert isinstance(world.clock, SystemClock)
 
 
+# Module scope: `start_in_subprocess` pickles the loop to reach a spawned child, and a class defined
+# inside the test would not pickle.
+class HeartbeatLoop:
+    """Control loop announcing every iteration of its body."""
+
+    def __init__(self, emitter: SignalEmitter):
+        self.emitter = emitter
+
+    def run(self, stop_reader, clock):
+        while not stop_reader.read().data:
+            self.emitter.emit('beat')
+            yield Sleep(0.01)
+
+
 class TestWorld:
     """Test the World class."""
 
@@ -244,17 +258,22 @@ def test_background_process(self):
         """Test that background processes will run simple control loop."""
         world = World()
         with world:
-            world.start_in_subprocess(dummy_process)
+            emitter, receiver = world.mp_pipes()
+            assert isinstance(receiver, SignalReceiver)
+            world.start_in_subprocess(HeartbeatLoop(emitter).run)
 
-            time.sleep(0.2)  # Some time to let the process run
             assert len(world.background_processes) == 1
 
+            # Stopping before the child reaches its loop body would leave the loop untested: the generator
+            # sees a set event on its first condition and returns without ever running the body.
+            deadline = time.monotonic() + 30
+            while receiver.read() is None:
+                assert time.monotonic() < deadline, 'background process never entered its control loop'
+                time.sleep(0.01)
+
             # We have to set the private event manually, because out of the scope of the context manager
             # we can't access exit code of the process
             world._stop_event.set()
-            # The child is spawned, so it boots a fresh interpreter and imports this module before it can
-            # observe the stop event — on a slow runner that outlasts any tight deadline. `join` returns the
-            # moment it exits, so a generous ceiling costs a passing run nothing.
             world.background_processes[0].join(timeout=30)
             assert not world.background_processes[0].is_alive()
             assert world.background_processes[0].exitcode == 0

positronic/simulator/libero/tests/test_e2e.py

@@ -13,7 +13,7 @@
 
 then run by explicit path (macOS renders via GLFW, no env var; Linux needs ``MUJOCO_GL=osmesa``)::
 
-    uv run --locked pytest positronic/simulator/libero/tests/test_e2e.py --no-cov
+    uv run --locked pytest positronic/simulator/libero/tests/test_e2e.py
 """
 
 import os

pyproject.toml

@@ -203,10 +203,6 @@ addopts = [
     # The suite waits on spawned processes and sockets about as much as it computes, so it scales with cores.
     # `-n0` puts it back in one process, which live logs and `--pdb` need.
     "-n", "auto",
-    "--cov=pimm",
-    "--cov=platform_client",
-    "--cov=positronic",
-    "--cov-report=term-missing",
     # Needs the `libero` extra and OSMesa; `libero-e2e.yaml` runs it by path, which `--ignore` allows.
     "--ignore=positronic/simulator/libero/tests/test_e2e.py",
 ]