[turtle] Use Literal for string params (#14874)

stdlib/turtle.pyi

@@ -221,16 +221,20 @@ class Terminator(Exception): ...
 class TurtleGraphicsError(Exception): ...
 
 class Shape:
-    def __init__(self, type_: str, data: _PolygonCoords | PhotoImage | None = None) -> None: ...
+    def __init__(
+        self, type_: Literal["polygon", "image", "compound"], data: _PolygonCoords | PhotoImage | None = None
+    ) -> None: ...
     def addcomponent(self, poly: _PolygonCoords, fill: _Color, outline: _Color | None = None) -> None: ...
 
 class TurtleScreen(TurtleScreenBase):
-    def __init__(self, cv: Canvas, mode: str = "standard", colormode: float = 1.0, delay: int = 10) -> None: ...
+    def __init__(
+        self, cv: Canvas, mode: Literal["standard", "logo", "world"] = "standard", colormode: float = 1.0, delay: int = 10
+    ) -> None: ...
     def clear(self) -> None: ...
     @overload
     def mode(self, mode: None = None) -> str: ...
     @overload
-    def mode(self, mode: str) -> None: ...
+    def mode(self, mode: Literal["standard", "logo", "world"]) -> None: ...
     def setworldcoordinates(self, llx: float, lly: float, urx: float, ury: float) -> None: ...
     def register_shape(self, name: str, shape: _PolygonCoords | Shape | None = None) -> None: ...
     @overload
@@ -289,7 +293,7 @@ class TNavigator:
     DEFAULT_MODE: str
     DEFAULT_ANGLEOFFSET: int
     DEFAULT_ANGLEORIENT: int
-    def __init__(self, mode: str = "standard") -> None: ...
+    def __init__(self, mode: Literal["standard", "logo", "world"] = "standard") -> None: ...
     def reset(self) -> None: ...
     def degrees(self, fullcircle: float = 360.0) -> None: ...
     def radians(self) -> None: ...
@@ -333,11 +337,11 @@ class TNavigator:
     seth = setheading
 
 class TPen:
-    def __init__(self, resizemode: str = "noresize") -> None: ...
+    def __init__(self, resizemode: Literal["auto", "user", "noresize"] = "noresize") -> None: ...
     @overload
     def resizemode(self, rmode: None = None) -> str: ...
     @overload
-    def resizemode(self, rmode: str) -> None: ...
+    def resizemode(self, rmode: Literal["auto", "user", "noresize"]) -> None: ...
     @overload
     def pensize(self, width: None = None) -> int: ...
     @overload
@@ -389,7 +393,7 @@ class TPen:
         fillcolor: _Color = ...,
         pensize: int = ...,
         speed: int = ...,
-        resizemode: str = ...,
+        resizemode: Literal["auto", "user", "noresize"] = ...,
         stretchfactor: tuple[float, float] = ...,
         outline: int = ...,
         tilt: float = ...,
@@ -524,7 +528,7 @@ def clear() -> None: ...
 @overload
 def mode(mode: None = None) -> str: ...
 @overload
-def mode(mode: str) -> None: ...
+def mode(mode: Literal["standard", "logo", "world"]) -> None: ...
 def setworldcoordinates(llx: float, lly: float, urx: float, ury: float) -> None: ...
 def register_shape(name: str, shape: _PolygonCoords | Shape | None = None) -> None: ...
 @overload
@@ -634,7 +638,7 @@ seth = setheading
 @overload
 def resizemode(rmode: None = None) -> str: ...
 @overload
-def resizemode(rmode: str) -> None: ...
+def resizemode(rmode: Literal["auto", "user", "noresize"]) -> None: ...
 @overload
 def pensize(width: None = None) -> int: ...
 @overload
@@ -683,7 +687,7 @@ def pen(
     fillcolor: _Color = ...,
     pensize: int = ...,
     speed: int = ...,
-    resizemode: str = ...,
+    resizemode: Literal["auto", "user", "noresize"] = ...,
     stretchfactor: tuple[float, float] = ...,
     outline: int = ...,
     tilt: float = ...,