Add support for configuration in pyproject.toml

Fix pytest-dev#1556

Author: nicoddemus

setup.py

@@ -13,6 +13,7 @@
     "pluggy>=0.12,<1.0",
     'importlib-metadata>=0.12;python_version<"3.8"',
     "wcwidth",
+    "toml",
 ]
 
 

src/_pytest/config/__init__.py

@@ -1126,16 +1126,22 @@ def _getini(self, name: str) -> Any:
                 if type is None:
                     return ""
                 return []
+        # coerce the values based on types
+        # note: some coercions are only required if we are reading from .ini files, because
+        # the file format doesn't contain type information; toml files however support
+        # data types and complex types such as lists directly, so many conversions are not
+        # necessary
         if type == "pathlist":
             dp = py.path.local(self.inifile).dirpath()
-            values = []
-            for relpath in shlex.split(value):
-                values.append(dp.join(relpath, abs=True))
-            return values
+            input_values = shlex.split(value) if isinstance(value, str) else value
+            return [dp.join(x, abs=True) for x in input_values]
         elif type == "args":
-            return shlex.split(value)
+            return shlex.split(value) if isinstance(value, str) else value
         elif type == "linelist":
-            return [t for t in map(lambda x: x.strip(), value.split("\n")) if t]
+            if isinstance(value, str):
+                return [t for t in map(lambda x: x.strip(), value.split("\n")) if t]
+            else:
+                return value
         elif type == "bool":
             return bool(_strtobool(value.strip()))
         else:

src/_pytest/config/findpaths.py

@@ -79,6 +79,33 @@ def _get_ini_config_from_setup_cfg(path: py.path.local) -> Optional[Dict[str, An
     return None
 
 
+def _get_ini_config_from_pyproject_toml(
+    path: py.path.local,
+) -> Optional[Dict[str, Any]]:
+    """Parses and validates a 'setup.cfg' file for pytest configuration.
+
+    'setup.cfg' files are only considered for pytest configuration if they contain a "[tool:pytest]"
+    section.
+
+    If a setup.cfg contains a "[pytest]" section, we raise a failure to indicate users that
+    plain "[pytest]" sections in setup.cfg files is no longer supported (#3086).
+    """
+    import toml
+
+    config = toml.load(path)
+
+    result = config.get("tool", {}).get("pytest", {}).get("ini", None)
+    if result is not None:
+        # convert all scalar values to strings for compatibility with other ini formats
+        # conversion to actual useful values is made by Config._getini
+        def make_scalar(v):
+            return v if isinstance(v, (list, tuple)) else str(v)
+
+        return {k: make_scalar(v) for k, v in result.items()}
+    else:
+        return None
+
+
 def getcfg(args):
     """
     Search the list of arguments for a valid ini-file for pytest,
@@ -88,6 +115,7 @@ def getcfg(args):
         ("pytest.ini", _get_ini_config_from_pytest_ini),
         ("tox.ini", _get_ini_config_from_tox_ini),
         ("setup.cfg", _get_ini_config_from_setup_cfg),
+        ("pyproject.toml", _get_ini_config_from_pyproject_toml),
     ]
     args = [x for x in args if not str(x).startswith("-")]
     if not args:

src/_pytest/pytester.py

@@ -686,6 +686,13 @@ def getinicfg(self, source):
         p = self.makeini(source)
         return py.iniconfig.IniConfig(p)["pytest"]
 
+    def makepyprojecttoml(self, source):
+        """Write a pyproject.toml file with 'source' as contents.
+
+        .. versionadded:: 6.0
+        """
+        return self.makefile(".toml", pyproject=source)
+
     def makepyfile(self, *args, **kwargs):
         r"""Shortcut for .makefile() with a .py extension.
         Defaults to the test name with a '.py' extension, e.g test_foobar.py, overwriting

testing/test_config.py

@@ -109,6 +109,16 @@ def test_ini_names(self, testdir, name, section):
         config = testdir.parseconfig()
         assert config.getini("minversion") == "1.0"
 
+    def test_pyproject_toml(self, testdir):
+        testdir.makepyprojecttoml(
+            """
+            [tool.pytest.ini]
+            minversion = "1.0"
+        """
+        )
+        config = testdir.parseconfig()
+        assert config.getini("minversion") == "1.0"
+
     def test_toxini_before_lower_pytestini(self, testdir):
         sub = testdir.tmpdir.mkdir("sub")
         sub.join("tox.ini").write(
@@ -287,63 +297,110 @@ def pytest_addoption(parser):
         assert val == "hello"
         pytest.raises(ValueError, config.getini, "other")
 
-    def test_addini_pathlist(self, testdir):
+    def make_conftest_for_pathlist(self, testdir):
         testdir.makeconftest(
             """
             def pytest_addoption(parser):
                 parser.addini("paths", "my new ini value", type="pathlist")
                 parser.addini("abc", "abc value")
         """
         )
+
+    def test_addini_pathlist_ini_files(self, testdir):
+        self.make_conftest_for_pathlist(testdir)
         p = testdir.makeini(
             """
             [pytest]
             paths=hello world/sub.py
         """
         )
+        self.check_config_pathlist(testdir, p)
+
+    def test_addini_pathlist_pyproject_toml(self, testdir):
+        self.make_conftest_for_pathlist(testdir)
+        p = testdir.makepyprojecttoml(
+            """
+            [tool.pytest.ini]
+            paths=["hello", "world/sub.py"]
+        """
+        )
+        self.check_config_pathlist(testdir, p)
+
+    def check_config_pathlist(self, testdir, config_path):
         config = testdir.parseconfig()
         values = config.getini("paths")
         assert len(values) == 2
-        assert values[0] == p.dirpath("hello")
-        assert values[1] == p.dirpath("world/sub.py")
+        assert values[0] == config_path.dirpath("hello")
+        assert values[1] == config_path.dirpath("world/sub.py")
         pytest.raises(ValueError, config.getini, "other")
 
-    def test_addini_args(self, testdir):
+    def make_conftest_for_args(self, testdir):
         testdir.makeconftest(
             """
             def pytest_addoption(parser):
                 parser.addini("args", "new args", type="args")
                 parser.addini("a2", "", "args", default="1 2 3".split())
         """
         )
+
+    def test_addini_args_ini_files(self, testdir):
+        self.make_conftest_for_args(testdir)
         testdir.makeini(
             """
             [pytest]
             args=123 "123 hello" "this"
-        """
+            """
         )
+        self.check_config_args(testdir)
+
+    def test_addini_args_pyproject_toml(self, testdir):
+        self.make_conftest_for_args(testdir)
+        testdir.makepyprojecttoml(
+            """
+            [tool.pytest.ini]
+            args = ["123", "123 hello", "this"]
+            """
+        )
+        self.check_config_args(testdir)
+
+    def check_config_args(self, testdir):
         config = testdir.parseconfig()
         values = config.getini("args")
-        assert len(values) == 3
         assert values == ["123", "123 hello", "this"]
         values = config.getini("a2")
         assert values == list("123")
 
-    def test_addini_linelist(self, testdir):
+    def make_conftest_for_linelist(self, testdir):
         testdir.makeconftest(
             """
             def pytest_addoption(parser):
                 parser.addini("xy", "", type="linelist")
                 parser.addini("a2", "", "linelist")
         """
         )
+
+    def test_addini_linelist_ini_files(self, testdir):
+        self.make_conftest_for_linelist(testdir)
         testdir.makeini(
             """
             [pytest]
             xy= 123 345
                 second line
         """
         )
+        self.check_config_linelist(testdir)
+
+    def test_addini_linelist_pprojecttoml(self, testdir):
+        self.make_conftest_for_linelist(testdir)
+        testdir.makepyprojecttoml(
+            """
+            [tool.pytest.ini]
+            xy = ["123 345", "second line"]
+        """
+        )
+        self.check_config_linelist(testdir)
+
+    def check_config_linelist(self, testdir):
         config = testdir.parseconfig()
         values = config.getini("xy")
         assert len(values) == 2