Merge pull request #4181 from pwohlhart/patch-1

Better error messaging in PIL.Image.fromarray
python-pillow · Nov 30, 2019 · 08cad40 · 08cad40
2 parents a776255 + 19a8a39
commit 08cad40
Show file tree

Hide file tree

Showing 2 changed files with 9 additions and 1 deletion.
diff --git a/Tests/test_image_array.py b/Tests/test_image_array.py
@@ -52,3 +52,8 @@ def test(mode):
         self.assertEqual(test("RGB"), ("RGB", (128, 100), True))
         self.assertEqual(test("RGBA"), ("RGBA", (128, 100), True))
         self.assertEqual(test("RGBX"), ("RGBA", (128, 100), True))
+
+        # Test mode is None with no "typestr" in the array interface
+        with self.assertRaises(TypeError):
+            wrapped = Wrapper(test("L"), {"shape": (100, 128)})
+            Image.fromarray(wrapped)
diff --git a/src/PIL/Image.py b/src/PIL/Image.py
@@ -2570,9 +2570,12 @@ def fromarray(obj, mode=None):
     if mode is None:
         try:
             typekey = (1, 1) + shape[2:], arr["typestr"]
-            mode, rawmode = _fromarray_typemap[typekey]
         except KeyError:
             raise TypeError("Cannot handle this data type")
+        try:
+            mode, rawmode = _fromarray_typemap[typekey]
+        except KeyError:
+            raise TypeError("Cannot handle this data type: %s, %s" % typekey)
     else:
         rawmode = mode
     if mode in ["1", "L", "I", "P", "F"]: