Delete an EXIF tag.

2 files changed, 59 insertions, 2 deletions

diff --git a/unittest/exif.py b/unittest/exif.py
index 1ce1d3c..6b463fd 100644
--- a/unittest/exif.py
+++ b/unittest/exif.py
@@ -36,6 +36,12 @@ class ImageMetadataMock(object):
     def _set_exif_tag_value(self, key, value):
         self.tags[key] = value
 
+    def _delete_exif_tag(self, key):
+        try:
+            del self.tags[key]
+        except KeyError:
+            pass
+
 
 class TestExifTag(unittest.TestCase):
 
@@ -221,3 +227,21 @@ class TestExifTag(unittest.TestCase):
         tag.value = 2
         self.failIfEqual(tag.value, old_value)
         self.assertEqual(tag.metadata.tags[tag.key], '2')
+
+    def test_del_value_no_metadata(self):
+        tag = ExifTag('Exif.Thumbnail.Orientation', 'Orientation',
+                      'Orientation', 'The image orientation viewed in terms ' \
+                      'of rows and columns.', 'Short', '1', 'top, left')
+        del tag.value
+        self.failIf(hasattr(tag, 'value'))
+
+    def test_del_value_with_metadata(self):
+        tag = ExifTag('Exif.Thumbnail.Orientation', 'Orientation',
+                      'Orientation', 'The image orientation viewed in terms ' \
+                      'of rows and columns.', 'Short', '1', 'top, left')
+        tag.metadata = ImageMetadataMock()
+        tag.metadata._set_exif_tag_value(tag.key, tag.to_string())
+        self.assertEqual(tag.metadata.tags, {tag.key: '1'})
+        del tag.value
+        self.failIf(hasattr(tag, 'value'))
+        self.failIf(tag.metadata.tags.has_key(tag.key))
diff --git a/unittest/metadata.py b/unittest/metadata.py
index 1055c85..029774a 100644
--- a/unittest/metadata.py
+++ b/unittest/metadata.py
@@ -52,6 +52,12 @@ class ImageMock(object):
     def setExifTag(self, key, value):
         self.tags['exif'][key] = value
 
+    def deleteExifTag(self, key):
+        try:
+            del self.tags['exif'][key]
+        except KeyError:
+            pass
+
     def iptcKeys(self):
         return self.tags['iptc'].keys()
 
@@ -197,11 +203,11 @@ class TestImageMetadata(unittest.TestCase):
         self.assertEqual(self.metadata._image.tags['exif'][tag.key],
                          tag.raw_value)
 
-    def test_set_exif_tag_overwrite_already_gotten(self):
+    def test_set_exif_tag_overwrite_already_cached(self):
         self.metadata.read()
         self._set_exif_tags()
         self.assertEqual(self.metadata._tags['exif'], {})
-        # Overwrite an existing tag already gotten
+        # Overwrite an existing tag already cached
         key = 'Exif.Photo.ExifVersion'
         tag = self.metadata._get_exif_tag(key)
         self.assertEqual(self.metadata._tags['exif'][key], tag)
@@ -242,6 +248,33 @@ class TestImageMetadata(unittest.TestCase):
         self.metadata._set_exif_tag_value(key, value)
         self.assertEqual(self.metadata._image.tags['exif'][key], value)
 
+    def test_delete_exif_tag_inexistent(self):
+        self.metadata.read()
+        self._set_exif_tags()
+        key = 'Exif.Image.Artist'
+        self.failUnlessRaises(KeyError, self.metadata._delete_exif_tag, key)
+
+    def test_delete_exif_tag_not_cached(self):
+        self.metadata.read()
+        self._set_exif_tags()
+        key = 'Exif.Image.DateTime'
+        self.assertEqual(self.metadata._tags['exif'], {})
+        self.assert_(self.metadata._image.tags['exif'].has_key(key))
+        self.metadata._delete_exif_tag(key)
+        self.assertEqual(self.metadata._tags['exif'], {})
+        self.failIf(self.metadata._image.tags['exif'].has_key(key))
+
+    def test_delete_exif_tag_cached(self):
+        self.metadata.read()
+        self._set_exif_tags()
+        key = 'Exif.Image.DateTime'
+        self.assert_(self.metadata._image.tags['exif'].has_key(key))
+        tag = self.metadata._get_exif_tag(key)
+        self.assertEqual(self.metadata._tags['exif'][key], tag)
+        self.metadata._delete_exif_tag(key)
+        self.assertEqual(self.metadata._tags['exif'], {})
+        self.failIf(self.metadata._image.tags['exif'].has_key(key))
+
     def test_iptc_keys(self):
         self.metadata.read()
         self._set_iptc_tags()