ci: parallelize the test suite and cut install/coverage overhead (#580)

Run pytest with -n auto (pytest-xdist) and COVERAGE_CORE=sysmon, enable the uv cache, and switch test output to -q. Cuts the test job from ~40min to ~4min without changing what's tested or the 60% coverage gate.

.github/workflows/ci.yml

@@ -23,6 +23,8 @@ jobs:
 
       - name: Install uv
         uses: astral-sh/setup-uv@v8.0.0
+        with:
+          enable-cache: true
 
       - name: Install dependencies
         run: uv sync --extra dev --extra framework-comparison --extra server
@@ -55,6 +57,8 @@ jobs:
 
       - name: Install uv
         uses: astral-sh/setup-uv@v8.0.0
+        with:
+          enable-cache: true
 
       - name: Install dependencies
         run: uv sync --extra dev --extra framework-comparison --extra server
@@ -63,8 +67,13 @@ jobs:
         run: uv run maturin develop --manifest-path rust/crates/openjarvis-python/Cargo.toml
 
       - name: Run tests
+        # COVERAGE_CORE=sysmon uses CPython 3.12's sys.monitoring backend,
+        # which is dramatically cheaper than the default C trace function.
+        # -n auto fans the suite out across all runner cores via pytest-xdist.
+        env:
+          COVERAGE_CORE: sysmon
         run: |
-          uv run pytest tests/ -v --tb=short -m "not live and not cloud and not hub" \
+          uv run pytest tests/ -n auto -q --tb=short -m "not live and not cloud and not hub" \
             --cov=openjarvis \
             --cov-report=term-missing \
             --cov-report=xml \
@@ -107,6 +116,8 @@ jobs:
 
       - name: Install uv
         uses: astral-sh/setup-uv@v8.0.0
+        with:
+          enable-cache: true
 
       - name: Install dependencies
         run: uv sync --extra dev --extra server

pyproject.toml

@@ -48,6 +48,7 @@ dev = [
     "pytest>=8",
     "pytest-asyncio>=0.24",
     "pytest-cov>=5",
+    "pytest-xdist>=3",
     "respx>=0.22",
     "ruff>=0.4",
     "pre-commit>=3.0",