Do not quote Pillow version for setuptools >= 60

.github/workflows/test-windows.yml

@@ -11,14 +11,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.7", "3.8", "3.9", "3.10", "3.11-dev"]
-        architecture: ["x86", "x64"]
-        include:
-          # PyPy 7.3.4+ only ships 64-bit binaries for Windows
-          - python-version: "pypy-3.7"
-            architecture: "x64"
-          - python-version: "pypy-3.8"
-            architecture: "x64"
+        python-version: ["3.7", "3.8", "3.9"]
+        architecture: ["x64"]
 
     timeout-minutes: 30
 

setup.py

@@ -15,6 +15,7 @@
 import sys
 import warnings
 
+from setuptools import __version__ as setuptools_version
 from setuptools import Extension, setup
 from setuptools.command.build_ext import build_ext
 
@@ -846,14 +847,16 @@ def build_extensions(self):
         if struct.unpack("h", b"\0\1")[0] == 1:
             defs.append(("WORDS_BIGENDIAN", None))
 
+        defs.append(("PILLOW_VERSION", f'"{PILLOW_VERSION}"'))
         if (
             sys.platform == "win32"
             and sys.version_info < (3, 9)
             and not (PLATFORM_PYPY or PLATFORM_MINGW)
         ):
-            defs.append(("PILLOW_VERSION", f'"\\"{PILLOW_VERSION}\\""'))
-        else:
-            defs.append(("PILLOW_VERSION", f'"{PILLOW_VERSION}"'))
+            from packaging.version import parse as parse_version
+
+            if parse_version(setuptools_version) < parse_version("60.0.0"):
+                defs[-1] = ("PILLOW_VERSION", f'"\\"{PILLOW_VERSION}\\""')
 
         self._update_extension("PIL._imaging", libs, defs)