Merge master into features

Conflicts:
	src/_pytest/_code/code.py
	src/_pytest/main.py

src/_pytest/_code/source.py

@@ -277,7 +277,7 @@ def compile_(  # noqa: F811
     return s.compile(filename, mode, flags, _genframe=_genframe)
 
 
-def getfslineno(obj) -> Tuple[Union[str, py.path.local], int]:
+def getfslineno(obj) -> Tuple[Optional[Union["Literal['']", py.path.local]], int]:
     """ Return source location (path, lineno) for the given object.
     If the source cannot be determined return ("", -1).