[ruff] Add ruff's check and autofix existing issues

Author: Pierre-Sassoulas

pyproject.toml

@@ -133,6 +133,7 @@ select = [
     "F",  # pyflakes
     "I",  # isort
     "UP", # pyupgrade
+    "RUF", # ruff
     "W",  # pycodestyle
 ]
 ignore = [
@@ -156,6 +157,12 @@ ignore = [
     "D402", # First line should not be the function's signature
     "D404", # First word of the docstring should not be "This"
     "D415", # First line should end with a period, question mark, or exclamation point
+    # ruff ignore
+    "RUF001", # String contains ambiguous character
+    "RUF003", # Comment contains ambiguous character
+    "RUF005", # Consider `(x, *y)` instead of concatenation
+    "RUF012", # Mutable class attributes should be annotated with `typing.ClassVar`
+    "RUF015", # Prefer `next(iter(x))` over single element slice
 ]
 
 [tool.ruff.format]

src/_pytest/_code/code.py

@@ -1018,7 +1018,7 @@ def _truncate_recursive_traceback(
             extraline: Optional[str] = (
                 "!!! Recursion error detected, but an error occurred locating the origin of recursion.\n"
                 "  The following exception happened when comparing locals in the stack frame:\n"
-                f"    {type(e).__name__}: {str(e)}\n"
+                f"    {type(e).__name__}: {e!s}\n"
                 f"  Displaying first and last {max_frames} stack frames out of {len(traceback)}."
             )
             # Type ignored because adding two instances of a List subtype

src/_pytest/_py/path.py

@@ -1105,9 +1105,7 @@ def pyimport(self, modname=None, ensuresyspath=True):
                 modname = self.purebasename
             spec = importlib.util.spec_from_file_location(modname, str(self))
             if spec is None or spec.loader is None:
-                raise ImportError(
-                    f"Can't find module {modname} at location {str(self)}"
-                )
+                raise ImportError(f"Can't find module {modname} at location {self!s}")
             mod = importlib.util.module_from_spec(spec)
             spec.loader.exec_module(mod)
             return mod

src/_pytest/compat.py

@@ -27,7 +27,7 @@
 # https://www.python.org/dev/peps/pep-0484/#support-for-singleton-types-in-unions
 class NotSetType(enum.Enum):
     token = 0
-NOTSET: Final = NotSetType.token  # noqa: E305
+NOTSET: Final = NotSetType.token
 # fmt: on
 
 

src/_pytest/config/__init__.py

@@ -671,7 +671,7 @@ def _importconftest(
                 if dirpath in path.parents or path == dirpath:
                     if mod in mods:
                         raise AssertionError(
-                            f"While trying to load conftest path {str(conftestpath)}, "
+                            f"While trying to load conftest path {conftestpath!s}, "
                             f"found that the module {mod} is already loaded with path {mod.__file__}. "
                             "This is not supposed to happen. Please report this issue to pytest."
                         )

src/_pytest/fixtures.py

@@ -1225,7 +1225,7 @@ def fixture(
 
 
 @overload
-def fixture(  # noqa: F811
+def fixture(
     fixture_function: None = ...,
     *,
     scope: "Union[_ScopeName, Callable[[str, Config], _ScopeName]]" = ...,
@@ -1239,7 +1239,7 @@ def fixture(  # noqa: F811
     ...
 
 
-def fixture(  # noqa: F811
+def fixture(
     fixture_function: Optional[FixtureFunction] = None,
     *,
     scope: "Union[_ScopeName, Callable[[str, Config], _ScopeName]]" = "function",
@@ -1673,7 +1673,7 @@ def parsefactories(
         raise NotImplementedError()
 
     @overload
-    def parsefactories(  # noqa: F811
+    def parsefactories(
         self,
         node_or_obj: object,
         nodeid: Optional[str],
@@ -1682,7 +1682,7 @@ def parsefactories(  # noqa: F811
     ) -> None:
         raise NotImplementedError()
 
-    def parsefactories(  # noqa: F811
+    def parsefactories(
         self,
         node_or_obj: Union[nodes.Node, object],
         nodeid: Union[str, NotSetType, None] = NOTSET,

src/_pytest/junitxml.py

@@ -375,7 +375,7 @@ def record_func(name: str, value: object) -> None:
 
     xml = request.config.stash.get(xml_key, None)
     if xml is not None:
-        record_func = xml.add_global_property  # noqa
+        record_func = xml.add_global_property
     return record_func
 
 

src/_pytest/main.py

@@ -726,12 +726,12 @@ def perform_collect(
         ...
 
     @overload
-    def perform_collect(  # noqa: F811
+    def perform_collect(
         self, args: Optional[Sequence[str]] = ..., genitems: bool = ...
     ) -> Sequence[Union[nodes.Item, nodes.Collector]]:
         ...
 
-    def perform_collect(  # noqa: F811
+    def perform_collect(
         self, args: Optional[Sequence[str]] = None, genitems: bool = True
     ) -> Sequence[Union[nodes.Item, nodes.Collector]]:
         """Perform the collection phase for this session.

src/_pytest/mark/structures.py

@@ -406,7 +406,7 @@ def normalize_mark_list(
     for mark in mark_list:
         mark_obj = getattr(mark, "mark", mark)
         if not isinstance(mark_obj, Mark):
-            raise TypeError(f"got {repr(mark_obj)} instead of Mark")
+            raise TypeError(f"got {mark_obj!r} instead of Mark")
         yield mark_obj
 
 

src/_pytest/python.py

@@ -358,7 +358,7 @@ def reportinfo(self) -> Tuple[Union["os.PathLike[str]", str], Optional[int], str
 # hook is not called for them.
 # fmt: off
 class _EmptyClass: pass  # noqa: E701
-IGNORED_ATTRIBUTES = frozenset.union(  # noqa: E305
+IGNORED_ATTRIBUTES = frozenset.union(
     frozenset(),
     # Module.
     dir(types.ModuleType("empty_module")),