chore: support pytest-cov and local reporting

Support pytest-cov by disabling include-ignored, allowing pytest-cov to
be run, which has built in support for coverage reporting is VS Code
making it super useful for checking coverage while writing tests.

Related issues:
- pytest-dev/pytest-cov#532
- pytest-dev/pytest-cov#369

Without this the coverage run will fail with an error about conflicting
coverage options.

Configure coverage paths so its easy to run coverage from the command
line with the data downloaded from the CI run, enabling easy analysis
of the coverage data.

Author: stevenh

pyproject.toml

@@ -224,6 +224,20 @@ omit = [
     "pydantic_ai_slim/pydantic_ai/ext/aci.py", # aci-sdk requires Python 3.10+ so cannot be added as an (optional) dependency
 ]
 branch = true
+# Disable include-ignored warnings as --source is enabled automatically causing a self conflict as per:
+# https://github.com/pytest-dev/pytest-cov/issues/532
+# https://github.com/pytest-dev/pytest-cov/issues/369
+# This prevents coverage being generated by pytest-cov which has direct editor support in VS Code,
+# making it super useful to check coverage while writing tests.
+disable_warnings = ["include-ignored"]
+
+[tool.coverage.paths]
+# Allow CI run assets to be downloaded an replicated locally.
+source = [
+    ".",
+    "/home/runner/work/pydantic-ai/pydantic-ai",
+    "/System/Volumes/Data/home/runner/work/pydantic-ai/pydantic-ai"
+]
 
 # https://coverage.readthedocs.io/en/latest/config.html#report
 [tool.coverage.report]