Merge pull request #30 from chireiden/bugfix/style-booleans

Fix parsing of boolean values in style lines

Author: FichteFoll

src/ass/data.py

@@ -98,6 +98,9 @@ def dump(v):
             return ""
 
         if isinstance(v, bool):
+            # Mimics behavior of booleans in styles,
+            # not that of field sections
+            # where "yes" and "no" would be more appropriate.
             return str(-int(v))
 
         if isinstance(v, timedelta):

src/ass/line.py

@@ -80,6 +80,18 @@ class Unknown(_Line):
     value = _Field("Value", str, default="")
 
 
+def _parse_bool_in_style(s: str) -> bool:
+    """Booleans in styles are parsed as integers and compared against 0.
+
+    This is unlike the normal "parse_bool" behavior.
+    It would probably be more sane to parse these as ints,
+    but that would be a breaking change to our API.
+
+    https://github.com/libass/libass/blob/534a5f8299c5ab3c2782856fcb843bfea47b7afc/libass/ass.c#L602-L605
+    """
+    return int(s) != 0
+
+
 class Style(_Line):
     """ A style line in ASS.
     """
@@ -92,10 +104,10 @@ class Style(_Line):
     secondary_color = _Field("SecondaryColour", Color, default=Color.RED)
     outline_color = _Field("OutlineColour", Color, default=Color.BLACK)
     back_color = _Field("BackColour", Color, default=Color.BLACK)
-    bold = _Field("Bold", bool, default=False)
-    italic = _Field("Italic", bool, default=False)
-    underline = _Field("Underline", bool, default=False)
-    strike_out = _Field("StrikeOut", bool, default=False)
+    bold = _Field("Bold", _parse_bool_in_style, default=False)
+    italic = _Field("Italic", _parse_bool_in_style, default=False)
+    underline = _Field("Underline", _parse_bool_in_style, default=False)
+    strike_out = _Field("StrikeOut", _parse_bool_in_style, default=False)
     scale_x = _Field("ScaleX", float, default=100)
     scale_y = _Field("ScaleY", float, default=100)
     spacing = _Field("Spacing", float, default=0)

tests/test.ass

@@ -2,6 +2,9 @@
 ScriptType: v4.00+
 PlayResX: 500
 PlayResY: 500
+WrapStyle: 0
+ScaledBorderAndShadow: yes
+YCbCr Matrix: None
 
 [Aegisub Project Garbage]
 Audio File: video.mkv
@@ -23,6 +26,7 @@ Another Line: 20
 [V4+ Styles]
 Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding
 Style: Default,Arial,20,&H00FFFFFF,&H000000FF,&H00000000,&H00000000,0,0,0,0,100,100,0,0,1,1,2,5,10,10,10,1
+Style: Alternative,Arial,20,&H00FFFFFF,&H000000FF,&H00000000,&H00000000,-1,-1,-1,-1,100,100,0,0,1,2,2,2,10,10,10,1
 
 [Events]
 Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text

tests/test_ass.py

@@ -9,43 +9,42 @@
 import ass
 
 folder = Path(__file__).parent
+test_ass_path = Path(folder, "test.ass")
 
 
-class TestDocument:
+@pytest.fixture
+def example_ass():
+    with test_ass_path.open("r", encoding='utf_8_sig') as f:
+        return f.read()
 
-    test_ass = Path(folder, "test.ass")
 
-    def test_parse_dump(self):
-        with self.test_ass.open("r", encoding='utf_8_sig') as f:
-            contents = f.read()
+@pytest.fixture
+def example_doc(example_ass):
+    return ass.parse(StringIO(example_ass))
 
-        doc = ass.parse(StringIO(contents))
-        out = StringIO()
-        doc.dump_file(out)
 
-        assert out.getvalue() == contents
+class TestDocument:
+
+    def test_parse_dump(self, example_doc, example_ass):
+        out = StringIO()
+        example_doc.dump_file(out)
+        assert out.getvalue() == example_ass
 
-    def test_parse_encoding(self):
-        with self.test_ass.open("r", encoding='utf_8') as f:
+    def test_parse_encoding_utf8(self):
+        with test_ass_path.open("r", encoding='utf_8') as f:
             with pytest.raises(ValueError):
                 ass.parse(f)
 
-        with self.test_ass.open("r", encoding='ascii') as f:
+    def test_parse_encoding_ascii(self):
+        with test_ass_path.open("r", encoding='ascii') as f:
             with pytest.raises(ValueError):
                 ass.parse(f)
 
-    def test_dump_encoding(self):
-        for encoding in ('utf_8_sig', 'utf-8-sig'):
-            with self.test_ass.open("r", encoding=encoding) as f:
-                doc = ass.parse(f)
-
-            with self.test_ass.open("r", encoding=encoding.upper()) as f:
-                doc = ass.parse(f)
-
+    def test_dump_encoding(self, example_doc):
         import tempfile
         with tempfile.TemporaryFile(mode='w', encoding='utf_8') as f:
             with pytest.warns(UserWarning):
-                doc.dump_file(f)
+                example_doc.dump_file(f)
 
 
 class TestSections:
@@ -80,9 +79,22 @@ def test_script_info(self):
         assert copy["Arbitrary Field"] == "hi"
         assert doc.play_res_x == 500
 
-    @pytest.mark.skip("Unimplemented")
-    def test_styles(self):
-        pass
+    def test_styles(self, example_doc):
+        assert len(example_doc.styles) == 2
+        default_style, alternative_style = example_doc.styles
+
+        assert default_style.name == "Default"
+        assert alternative_style.name == "Alternative"
+
+        assert default_style.bold is False
+        assert default_style.italic is False
+        assert default_style.underline is False
+        assert default_style.strike_out is False
+
+        assert alternative_style.bold is True
+        assert alternative_style.italic is True
+        assert alternative_style.underline is True
+        assert alternative_style.strike_out is True
 
     @pytest.mark.skip("Unimplemented")
     def test_events(self):