config: convert ini type None to string earlier

Do it early so later code doesn't have to deal with `type=None`.

Author: bluetech

src/_pytest/config/__init__.py

@@ -1710,8 +1710,6 @@ def _getini(self, name: str):
                     f"Expected a float string for option {name} of type float, but got: {value!r}"
                 ) from None
             return float(value)
-        elif type is None:
-            return value
         else:
             return self._getini_unknown_type(name, type, value)
 

src/_pytest/config/argparsing.py

@@ -50,7 +50,7 @@ def __init__(
         self._groups: list[OptionGroup] = []
         self._processopt = processopt
         self._usage = usage
-        self._inidict: dict[str, tuple[str, str | None, Any]] = {}
+        self._inidict: dict[str, tuple[str, str, Any]] = {}
         self._ininames: list[str] = []
         # Maps alias -> canonical name.
         self._ini_aliases: dict[str, str] = {}
@@ -238,6 +238,8 @@ def addini(
             "int",
             "float",
         )
+        if type is None:
+            type = "string"
         if default is NOT_SET:
             default = get_ini_default_for_type(type)
 
@@ -255,16 +257,13 @@ def addini(
 def get_ini_default_for_type(
     type: Literal[
         "string", "paths", "pathlist", "args", "linelist", "bool", "int", "float"
-    ]
-    | None,
+    ],
 ) -> Any:
     """
     Used by addini to get the default value for a given ini-option type, when
     default is not supplied.
     """
-    if type is None:
-        return ""
-    elif type in ("paths", "pathlist", "args", "linelist"):
+    if type in ("paths", "pathlist", "args", "linelist"):
         return []
     elif type == "bool":
         return False

src/_pytest/helpconfig.py

@@ -186,8 +186,6 @@ def showhelp(config: Config) -> None:
     indent = " " * indent_len
     for name in config._parser._ininames:
         help, type, _default = config._parser._inidict[name]
-        if type is None:
-            type = "string"
         if help is None:
             raise TypeError(f"help argument cannot be None for {name}")
         spec = f"{name} ({type}):"