MNT: eliminate a private Enum subclass

tacaswell · tacaswell · commit e702b0666aa9 · 2024-12-20T16:09:18.000-05:00
We used this to save duplicating two functions in string Enums, however the
base class is failing mypy validation as an empty Enum class.

There may be a better way to do this by silencing the checker, but if it is
mypy specific we might have to play whack-a-mole with every type checker.  I
tried a couple permutations of moving the `Enum` inheritance around, but for
meta-class reasons it appears that the enum-related special methods must be
directly in the class the sub-classes Enum.
diff --git a/lib/matplotlib/_enums.py b/lib/matplotlib/_enums.py
@@ -14,17 +14,7 @@
 from matplotlib import _docstring
 
 
-class _AutoStringNameEnum(Enum):
-    """Automate the ``name = 'name'`` part of making a (str, Enum)."""
-
-    def _generate_next_value_(name, start, count, last_values):
-        return name
-
-    def __hash__(self):
-        return str(self).__hash__()
-
-
-class JoinStyle(str, _AutoStringNameEnum):
+class JoinStyle(str, Enum):
     """
     Define how the connection between two line segments is drawn.
 
@@ -79,6 +69,12 @@ class JoinStyle(str, _AutoStringNameEnum):
 
     """
 
+    def _generate_next_value_(name, start, count, last_values):
+        return name
+
+    def __hash__(self):
+        return str(self).__hash__()
+
     miter = auto()
     round = auto()
     bevel = auto()
@@ -116,7 +112,7 @@ def plot_angle(ax, x, y, angle, style):
         + "}"
 
 
-class CapStyle(str, _AutoStringNameEnum):
+class CapStyle(str, Enum):
     r"""
     Define how the two endpoints (caps) of an unclosed line are drawn.
 
@@ -151,6 +147,13 @@ class CapStyle(str, _AutoStringNameEnum):
         CapStyle.demo()
 
     """
+
+    def _generate_next_value_(name, start, count, last_values):
+        return name
+
+    def __hash__(self):
+        return str(self).__hash__()
+
     butt = auto()
     projecting = auto()
     round = auto()
diff --git a/lib/matplotlib/_enums.pyi b/lib/matplotlib/_enums.pyi
@@ -1,17 +1,14 @@
 from typing import cast
 from enum import Enum
 
-class _AutoStringNameEnum(Enum):
-    def __hash__(self) -> int: ...
-
-class JoinStyle(str, _AutoStringNameEnum):
+class JoinStyle(str, Enum):
     miter = cast(str, ...)
     round = cast(str, ...)
     bevel = cast(str, ...)
     @staticmethod
     def demo() -> None: ...
 
-class CapStyle(str, _AutoStringNameEnum):
+class CapStyle(str, Enum):
     butt = cast(str, ...)
     projecting = cast(str, ...)
     round = cast(str, ...)
