Merge pull request #3616 from wbadart/master

_util.isPath returns True for pathlib.Path objects

Tests/test_util.py

@@ -35,6 +35,18 @@ class TestUtil(PillowTestCase):
         # Assert
         self.assertTrue(it_is)
 
+    @unittest.skipIf(not _util.py36, 'os.path support for Paths added in 3.6')
+    def test_path_obj_is_path(self):
+        # Arrange
+        from pathlib import Path
+        test_path = Path('filename.ext')
+
+        # Act
+        it_is = _util.isPath(test_path)
+
+        # Assert
+        self.assertTrue(it_is)
+
     def test_is_not_path(self):
         # Arrange
         filename = self.tempfile("temp.ext")

src/PIL/_util.py

@@ -2,13 +2,20 @@ import os
 import sys
 
 py3 = sys.version_info.major >= 3
+py36 = sys.version_info[0:2] >= (3, 6)
 
 if py3:
     def isStringType(t):
         return isinstance(t, str)
 
-    def isPath(f):
-        return isinstance(f, (bytes, str))
+    if py36:
+        from pathlib import Path
+
+        def isPath(f):
+            return isinstance(f, (bytes, str, Path))
+    else:
+        def isPath(f):
+            return isinstance(f, (bytes, str))
 else:
     def isStringType(t):
         return isinstance(t, basestring)  # noqa: F821