Fix custom TOML config files passed with -c

AUTHORS

@@ -135,6 +135,7 @@ David Peled
 David Szotten
 David Vierra
 Daw-Ran Liou
+Debaditya Hait
 Debi Mishra
 Denis Cherednichenko
 Denis Kirisov

changelog/14705.bugfix.rst

@@ -0,0 +1,2 @@
+Custom TOML configuration files selected with :option:`-c` now read options from
+the ``[pytest]`` table instead of ``[tool.pytest]``.

doc/en/reference/customize.rst

@@ -32,6 +32,9 @@ pytest.toml
 
 Alternatively, the hidden version ``.pytest.toml`` can be used.
 
+A TOML configuration file with a custom name can be loaded using :option:`-c`;
+like ``pytest.toml``, it uses the ``[pytest]`` table.
+
 .. tab:: toml
 
     .. code-block:: toml

src/_pytest/config/findpaths.py

@@ -92,7 +92,7 @@ def load_config_dict_from_file(
 
     # '.toml' files are considered if they contain a [tool.pytest] table (toml mode)
     # or [tool.pytest.ini_options] table (ini mode) for pyproject.toml,
-    # or [pytest] table (toml mode) for pytest.toml/.pytest.toml.
+    # or [pytest] table (toml mode) for other TOML configuration files.
     elif filepath.suffix == ".toml":
         if sys.version_info >= (3, 11):
             import tomllib
@@ -105,8 +105,8 @@ def load_config_dict_from_file(
         except tomllib.TOMLDecodeError as exc:
             raise UsageError(f"{filepath}: {exc}") from exc
 
-        # pytest.toml and .pytest.toml use [pytest] table directly.
-        if filepath.name in ("pytest.toml", ".pytest.toml"):
+        # TOML configuration files other than pyproject.toml use [pytest] directly.
+        if filepath.name != "pyproject.toml":
             if "pytest" in config:
                 # TOML mode - preserve native TOML types.
                 return {
@@ -122,7 +122,7 @@ def load_config_dict_from_file(
                     f"[pytest] table (found top-level options: "
                     f"{', '.join(top_level_options)})"
                 )
-            # "pytest.toml" files are always the source of configuration, even if empty.
+            # These files are always the source of configuration, even if empty.
             return {}
 
         # pyproject.toml uses [tool.pytest] or [tool.pytest.ini_options].

testing/test_config.py

@@ -766,8 +766,8 @@ def pytest_addoption(parser):
         pytester.makefile(
             ".toml",
             custom="""
-                [tool.pytest.ini_options]
-                custom = 1
+                [pytest]
+                custom = "1"
                 value = [
                 ]  # this is here on purpose, as it makes this an invalid '.ini' file
             """,
@@ -777,6 +777,29 @@ def pytest_addoption(parser):
         config = pytester.parseconfig("--config-file", "custom.toml")
         assert config.getini("custom") == "1"
 
+    def test_custom_toml_config_file_is_loaded(self, pytester: Pytester) -> None:
+        pytester.makepyfile(
+            bench_example="""
+            def bench_example():
+                pass
+            """
+        )
+        pytester.makefile(
+            ".toml",
+            pytest_benchmark="""
+            [pytest]
+            python_files = ["bench_*.py"]
+            python_functions = ["bench_*"]
+            """,
+        )
+
+        result = pytester.runpytest(
+            "-c", "pytest_benchmark.toml", "--collect-only", "-q"
+        )
+
+        assert result.ret == ExitCode.OK
+        result.stdout.fnmatch_lines(["bench_example.py::bench_example"])
+
     def test_absolute_win32_path(self, pytester: Pytester) -> None:
         temp_ini_file = pytester.makeini("[pytest]")
         from os.path import normpath

testing/test_findpaths.py

@@ -73,7 +73,7 @@ def test_invalid_toml_file(self, tmp_path: Path) -> None:
             load_config_dict_from_file(fn)
 
     def test_custom_toml_file(self, tmp_path: Path) -> None:
-        """.toml files without [tool.pytest] are not considered for configuration."""
+        """Custom .toml files without [pytest] have no configuration values."""
         fn = tmp_path / "myconfig.toml"
         fn.write_text(
             dedent(
@@ -84,12 +84,11 @@ def test_custom_toml_file(self, tmp_path: Path) -> None:
             ),
             encoding="utf-8",
         )
-        assert load_config_dict_from_file(fn) is None
+        assert load_config_dict_from_file(fn) == {}
 
-    def test_valid_toml_file(self, tmp_path: Path) -> None:
-        """.toml files with [tool.pytest.ini_options] are read correctly, including changing
-        data types to str/list for compatibility with other configuration options."""
-        fn = tmp_path / "myconfig.toml"
+    def test_pyproject_toml_ini_options(self, tmp_path: Path) -> None:
+        """[tool.pytest.ini_options] values are converted for INI compatibility."""
+        fn = tmp_path / "pyproject.toml"
         fn.write_text(
             dedent(
                 """
@@ -111,7 +110,35 @@ def test_valid_toml_file(self, tmp_path: Path) -> None:
             "heterogeneous_array": ConfigValue([1, "str"], origin="file", mode="ini"),
         }
 
-    def test_native_toml_config(self, tmp_path: Path) -> None:
+    def test_custom_toml_native_config(self, tmp_path: Path) -> None:
+        """Custom .toml files read native configuration from [pytest]."""
+        fn = tmp_path / "myconfig.toml"
+        fn.write_text(
+            dedent(
+                """
+                [pytest]
+                xfail_strict = true
+                testpaths = ["tests", "integration"]
+                """
+            ),
+            encoding="utf-8",
+        )
+
+        assert load_config_dict_from_file(fn) == {
+            "xfail_strict": ConfigValue(True, origin="file", mode="toml"),
+            "testpaths": ConfigValue(
+                ["tests", "integration"], origin="file", mode="toml"
+            ),
+        }
+
+    def test_custom_toml_ignores_pyproject_table(self, tmp_path: Path) -> None:
+        """Custom .toml files do not read configuration from [tool.pytest]."""
+        fn = tmp_path / "myconfig.toml"
+        fn.write_text("[tool.pytest]\nxfail_strict = true", encoding="utf-8")
+
+        assert load_config_dict_from_file(fn) == {}
+
+    def test_pyproject_native_toml_config(self, tmp_path: Path) -> None:
         """[tool.pytest] sections with native types are parsed correctly without coercion."""
         fn = tmp_path / "pyproject.toml"
         fn.write_text(