Updated deprecation timeline

Author: radarhere

Tests/test_deprecate.py

@@ -9,9 +9,9 @@
     "version, expected",
     [
         (
-            12,
-            "Old thing is deprecated and will be removed in Pillow 12 "
-            r"\(2025-10-15\)\. Use new thing instead\.",
+            13,
+            "Old thing is deprecated and will be removed in Pillow 13 "
+            r"\(2026-10-15\)\. Use new thing instead\.",
         ),
         (
             None,
@@ -53,18 +53,18 @@ def test_old_version(deprecated: str, plural: bool, expected: str) -> None:
 
 def test_plural() -> None:
     expected = (
-        r"Old things are deprecated and will be removed in Pillow 12 \(2025-10-15\)\. "
+        r"Old things are deprecated and will be removed in Pillow 13 \(2026-10-15\)\. "
         r"Use new thing instead\."
     )
     with pytest.warns(DeprecationWarning, match=expected):
-        _deprecate.deprecate("Old things", 12, "new thing", plural=True)
+        _deprecate.deprecate("Old things", 13, "new thing", plural=True)
 
 
 def test_replacement_and_action() -> None:
     expected = "Use only one of 'replacement' and 'action'"
     with pytest.raises(ValueError, match=expected):
         _deprecate.deprecate(
-            "Old thing", 12, replacement="new thing", action="Upgrade to new thing"
+            "Old thing", 13, replacement="new thing", action="Upgrade to new thing"
         )
 
 
@@ -77,16 +77,16 @@ def test_replacement_and_action() -> None:
 )
 def test_action(action: str) -> None:
     expected = (
-        r"Old thing is deprecated and will be removed in Pillow 12 \(2025-10-15\)\. "
+        r"Old thing is deprecated and will be removed in Pillow 13 \(2026-10-15\)\. "
         r"Upgrade to new thing\."
     )
     with pytest.warns(DeprecationWarning, match=expected):
-        _deprecate.deprecate("Old thing", 12, action=action)
+        _deprecate.deprecate("Old thing", 13, action=action)
 
 
 def test_no_replacement_or_action() -> None:
     expected = (
-        r"Old thing is deprecated and will be removed in Pillow 12 \(2025-10-15\)"
+        r"Old thing is deprecated and will be removed in Pillow 13 \(2026-10-15\)"
     )
     with pytest.warns(DeprecationWarning, match=expected):
-        _deprecate.deprecate("Old thing", 12)
+        _deprecate.deprecate("Old thing", 13)

src/PIL/_deprecate.py

@@ -46,8 +46,6 @@ def deprecate(
     elif when <= int(__version__.split(".")[0]):
         msg = f"{deprecated} {is_} deprecated and should be removed."
         raise RuntimeError(msg)
-    elif when == 12:
-        removed = "Pillow 12 (2025-10-15)"
     elif when == 13:
         removed = "Pillow 13 (2026-10-15)"
     else: