img: add Image.ext

Steve Canny · Steve Canny · commit 374b50514319 · 2014-03-01T01:35:31.000-08:00
Also refactored other ext usage to leave off the leading dot.
diff --git a/docx/image/__init__.py b/docx/image/__init__.py
@@ -77,7 +77,7 @@ def ext(self):
         a load filename it is used. Otherwise a canonical extension is
         assigned based on the content type.
         """
-        return os.path.splitext(self._filename)[1]
+        return os.path.splitext(self._filename)[1][1:]
 
     @property
     def filename(self):
diff --git a/docx/image/image.py b/docx/image/image.py
@@ -53,6 +53,16 @@ def content_type(self):
         """
         return self._image_header.content_type
 
+    @lazyproperty
+    def ext(self):
+        """
+        The file extension for the image. If an actual one is available from
+        a load filename it is used. Otherwise a canonical extension is
+        assigned based on the content type. Does not contain the leading
+        period, e.g. 'jpg', not '.jpg'.
+        """
+        return os.path.splitext(self._filename)[1][1:]
+
     @property
     def px_width(self):
         """
diff --git a/docx/package.py b/docx/package.py
@@ -101,12 +101,12 @@ def _get_by_sha1(self, sha1):
     def _next_image_partname(self, ext):
         """
         The next available image partname, starting from
-        ``/word/media/image1{ext}`` where unused numbers are reused. The
+        ``/word/media/image1.{ext}`` where unused numbers are reused. The
         partname is unique by number, without regard to the extension. *ext*
-        must include the leading period.
+        does not include the leading period.
         """
         def image_partname(n):
-            return PackURI('/word/media/image%d%s' % (n, ext))
+            return PackURI('/word/media/image%d.%s' % (n, ext))
         used_numbers = [image_part.partname.idx for image_part in self]
         for n in range(1, len(self)+1):
             if not n in used_numbers:
diff --git a/tests/image/test_image.py b/tests/image/test_image.py
@@ -64,6 +64,10 @@ def it_knows_the_image_dimensions(self, dimensions_fixture):
         assert image.px_width == px_width
         assert image.px_height == px_height
 
+    def it_knows_the_image_filename_extension(self):
+        image = Image(None, 'foobar.png', None)
+        assert image.ext == 'png'
+
     def it_knows_the_horz_and_vert_dpi_of_the_image(self, dpi_fixture):
         image_header_, horz_dpi, vert_dpi = dpi_fixture
         image = Image(None, None, image_header_)
@@ -240,13 +244,13 @@ def it_can_construct_from_an_image_stream(self):
     def it_knows_the_extension_of_a_file_based_image(self):
         image_file_path = test_file('monty-truth.png')
         image = Image_OLD.from_file(image_file_path)
-        assert image.ext == '.png'
+        assert image.ext == 'png'
 
     def it_knows_the_extension_of_a_stream_based_image(self):
         image_file_path = test_file('monty-truth.png')
         with open(image_file_path, 'rb') as image_file_stream:
             image = Image_OLD.from_file(image_file_stream)
-        assert image.ext == '.png'
+        assert image.ext == 'png'
 
     def it_correctly_characterizes_a_few_known_images(
             self, known_image_fixture):
@@ -268,16 +272,16 @@ def it_correctly_characterizes_a_few_known_images(
     @pytest.fixture(params=[0, 1, 2, 3, 4, 5, 6, 7, 8, 9])
     def known_image_fixture(self, request):
         cases = (
-            ('python.bmp',       ('.bmp',  CT.BMP,   211,   71,  72,  72)),
-            ('sonic.gif',        ('.gif',  CT.GIF,   290,  360,  72,  72)),
-            ('python-icon.jpeg', ('.jpg',  CT.JPEG,  204,  204,  72,  72)),
-            ('300-dpi.jpg',      ('.jpg',  CT.JPEG, 1504, 1936, 300, 300)),
-            ('monty-truth.png',  ('.png',  CT.PNG,   150,  214,  72,  72)),
-            ('150-dpi.png',      ('.png',  CT.PNG,   901, 1350, 150, 150)),
-            ('300-dpi.png',      ('.png',  CT.PNG,   860,  579, 300, 300)),
-            ('72-dpi.tiff',      ('.tiff', CT.TIFF,   48,   48,  72,  72)),
-            ('300-dpi.TIF',      ('.tiff', CT.TIFF, 2464, 3248, 300, 300)),
-            ('CVS_LOGO.WMF',     ('.wmf',  CT.X_WMF, 149,   59,  72,  72)),
+            ('python.bmp',       ('bmp',  CT.BMP,   211,   71,  72,  72)),
+            ('sonic.gif',        ('gif',  CT.GIF,   290,  360,  72,  72)),
+            ('python-icon.jpeg', ('jpg',  CT.JPEG,  204,  204,  72,  72)),
+            ('300-dpi.jpg',      ('jpg',  CT.JPEG, 1504, 1936, 300, 300)),
+            ('monty-truth.png',  ('png',  CT.PNG,   150,  214,  72,  72)),
+            ('150-dpi.png',      ('png',  CT.PNG,   901, 1350, 150, 150)),
+            ('300-dpi.png',      ('png',  CT.PNG,   860,  579, 300, 300)),
+            ('72-dpi.tiff',      ('tiff', CT.TIFF,   48,   48,  72,  72)),
+            ('300-dpi.TIF',      ('tiff', CT.TIFF, 2464, 3248, 300, 300)),
+            ('CVS_LOGO.WMF',     ('wmf',  CT.X_WMF, 149,   59,  72,  72)),
         )
         image_filename, characteristics = cases[request.param]
         return image_filename, characteristics
diff --git a/tests/test_package.py b/tests/test_package.py
@@ -129,7 +129,7 @@ def next_partname_fixture(self, request):
         for n in existing_partname_numbers:
             image_part_ = self._image_part_with_partname_(request, n)
             image_parts.append(image_part_)
-        ext = '.png'
+        ext = 'png'
         expected_image_partname = self._image_partname(
             expected_partname_number
         )

Original file line number	Diff line number	Diff line change
`@@ -129,7 +129,7 @@ def next_partname_fixture(self, request):`
`129`	`129`	`for n in existing_partname_numbers:`
`130`	`130`	`image_part_ = self._image_part_with_partname_(request, n)`
`131`	`131`	`image_parts.append(image_part_)`
`132`		`- ext = '.png'`
	`132`	`+ ext = 'png'`
`133`	`133`	`expected_image_partname = self._image_partname(`
`134`	`134`	`expected_partname_number`
`135`	`135`	`)`