PICARD-1412: Consider deleted tags as changed

picard/file.py

@@ -501,7 +501,7 @@ class File(QtCore.QObject, Item):
         for name in names:
             if not name.startswith('~') and self.supports_tag(name):
                 new_values = new_metadata.getall(name)
-                if not (new_values or clear_existing_tags):
+                if not (new_values or clear_existing_tags or new_metadata.deleted_tags):
                     continue
                 orig_values = self.orig_metadata.getall(name)
                 if orig_values != new_values:

picard/metadata.py

@@ -126,7 +126,9 @@ class Metadata(dict):
                 else:
                     score = similarity2(a, b)
                 parts.append((score, weight))
-
+            elif (a and name in other.deleted_tags
+                  or b and name in self.deleted_tags):
+                parts.append((0, weight))
         return linear_combination_of_weights(parts)
 
     def compare_to_release(self, release, weights):

test/test_metadata.py

@@ -152,3 +152,38 @@ class MetadataTest(PicardTestCase):
             actual = Metadata.length_score(a, b)
             self.assertAlmostEqual(expected, actual,
                                    msg="a={a}, b={b}".format(a=a, b=b))
+
+    def test_compare_is_equal(self):
+        m1 = Metadata()
+        m1["title"] = "title1"
+        m1["tracknumber"] = "2"
+        m1.length = 360
+        m2 = Metadata()
+        m2["title"] = "title1"
+        m2["tracknumber"] = "2"
+        m2.length = 360
+        self.assertEqual(m1.compare(m2), m2.compare(m1))
+        self.assertEqual(m1.compare(m2), 1)
+
+    def test_compare_lengths(self):
+        m1 = Metadata()
+        m1.length = 360
+        m2 = Metadata()
+        m2.length = 300
+        self.assertAlmostEqual(m1.compare(m2), 0.998)
+
+    def test_compare_tracknumber_difference(self):
+        m1 = Metadata()
+        m1["tracknumber"] = "1"
+        m2 = Metadata()
+        m2["tracknumber"] = "2"
+        self.assertEqual(m1.compare(m2), 0)
+
+    def test_compare_deleted(self):
+        m1 = Metadata()
+        m1["artist"] = "TheArtist"
+        m1["title"] = "title1"
+        m2 = Metadata()
+        m2["artist"] = "TheArtist"
+        m2.delete("title")
+        self.assertTrue(m1.compare(m2) < 1)