Use relative paths in Coverage.py configuration

nathanjmcdougall · nathanjmcdougall · commit 4fc975829d78 · 2025-12-29T10:26:36.000+13:00
diff --git a/pyproject.toml b/pyproject.toml
@@ -169,6 +169,7 @@ log_cli_level = "INFO"
 minversion = "7"
 
 [tool.coverage.run]
+relative_files = true
 source = [ "src" ]
 omit = [ "*/pytest-of-*/*", "*/_temp/*" ]
 
diff --git a/src/usethis/_tool/impl/coverage_py.py b/src/usethis/_tool/impl/coverage_py.py
@@ -147,6 +147,32 @@ def _get_source():
                         ),
                     },
                 ),
+                ConfigItem(
+                    # https://github.com/usethis-python/usethis-python/issues/930
+                    # This config helps ensure reports generated in CI environments
+                    # have consistent paths between jobs, by forcing them to be relative
+                    description="Relative Files Configuration",
+                    root={
+                        Path(".coveragerc"): ConfigEntry(
+                            keys=["run", "relative_files"], get_value=lambda: "true"
+                        ),
+                        Path(".coveragerc.toml"): ConfigEntry(
+                            keys=["run", "relative_files"], get_value=lambda: True
+                        ),
+                        Path("setup.cfg"): ConfigEntry(
+                            keys=["coverage:run", "relative_files"],
+                            get_value=lambda: "true",
+                        ),
+                        Path("tox.ini"): ConfigEntry(
+                            keys=["coverage:run", "relative_files"],
+                            get_value=lambda: "true",
+                        ),
+                        Path("pyproject.toml"): ConfigEntry(
+                            keys=["tool", "coverage", "run", "relative_files"],
+                            get_value=lambda: True,
+                        ),
+                    },
+                ),
                 ConfigItem(
                     description="Report Configuration",
                     root={
diff --git a/tests/usethis/_core/test_core_tool.py b/tests/usethis/_core/test_core_tool.py
@@ -436,6 +436,7 @@ def test_coverage_rc_file(self, uv_init_dir: Path):
 [run]
 source =
     src
+relative_files = true
 
 [report]
 exclude_also =
@@ -464,6 +465,7 @@ def test_tox_ini_file(self, uv_init_dir: Path):
 [coverage:run]
 source =
     src
+relative_files = true
 
 [coverage:report]
 exclude_also =
diff --git a/tests/usethis/_tool/impl/test_coverage_py.py b/tests/usethis/_tool/impl/test_coverage_py.py
@@ -107,3 +107,19 @@ def test_coveragerc_preferred_over_coveragerc_toml(self, tmp_path: Path):
             assert (tmp_path / ".coveragerc.toml").read_text() == (
                 '[run]\nsource = ["existing"]\n'
             )
+
+        def test_relative_files_set_to_true(self, tmp_path: Path):
+            # Arrange
+            (tmp_path / "pyproject.toml").write_text("""\
+[project]
+name = "example"
+version = "0.1.0"
+""")
+
+            # Act
+            with change_cwd(tmp_path), files_manager():
+                CoveragePyTool().add_configs()
+
+            # Assert
+            content = (tmp_path / "pyproject.toml").read_text()
+            assert "relative_files = true" in content
