Fix error when replaceable field missing

CHANGELOG.md

@@ -0,0 +1,9 @@
+# Changelog
+
+### 0.1.1 (2021-09-09)
+
+* Fixed issue when attempting to replace a missing field.
+
+### 0.1 (2021-09-08)
+
+* Initial release.

beetsplug/__init__.py

@@ -1,2 +1,2 @@
 from pkgutil import extend_path
-__path__ = extend_path(__path__, __name__)
+__path__ = extend_path(__path__, __name__)

beetsplug/importreplace.py

@@ -7,36 +7,40 @@
 
 
 class ImportReplace(BeetsPlugin):
-    item_fields = set()
-    album_fields = set()
-    replacements = []
+    _item_fields = set()
+    _album_fields = set()
+    _replacements = []
 
     def __init__(self):
         super(ImportReplace, self).__init__()
-        self.item_fields = self.config['item_fields'].as_str_seq()
-        self.album_fields = self.config['album_fields'].as_str_seq()
+        self._item_fields = self.config['item_fields'].as_str_seq()
+        self._album_fields = self.config['album_fields'].as_str_seq()
         for pattern, repl in self.config['replace'].get(dict).items():
             repl = repl or ''
-            self.replacements.append((re.compile(pattern), repl))
-        self.register_listener('trackinfo_received', self.trackinfo_received)
-        self.register_listener('albuminfo_received', self.albuminfo_received)
+            self._replacements.append((re.compile(pattern), repl))
+        self.register_listener('trackinfo_received', self._trackinfo_received)
+        self.register_listener('albuminfo_received', self._albuminfo_received)
 
-    def trackinfo_received(self, info: TrackInfo):
-        for field in self.item_fields:
+    def _trackinfo_received(self, info: TrackInfo):
+        for field in self._item_fields:
             if field in info:
-                replaced = self.replace_field(info.__getattr__(field))
-                info.__setattr__(field, replaced)
+                value = info.__getattr__(field)
+                if value:
+                    replaced = self._replace_field(value)
+                    info.__setattr__(field, replaced)
 
-    def albuminfo_received(self, info: AlbumInfo):
-        for field in self.album_fields:
+    def _albuminfo_received(self, info: AlbumInfo):
+        for field in self._album_fields:
             if field in info:
-                replaced = self.replace_field(info.__getattr__(field))
-                info.__setattr__(field, replaced)
+                value = info.__getattr__(field)
+                if value:
+                    replaced = self._replace_field(value)
+                    info.__setattr__(field, replaced)
         for track in info.tracks:
-            self.trackinfo_received(track)
+            self._trackinfo_received(track)
 
-    def replace_field(self, text: str) -> str:
-        return reduce(self.replace, self.replacements, text)
+    def _replace_field(self, text: str) -> str:
+        return reduce(self._replace, self._replacements, text)
 
-    def replace(self, text: str, replacement: (Pattern, str)) -> str:
+    def _replace(self, text: str, replacement: (Pattern, str)) -> str:
         return replacement[0].sub(repl=replacement[1], string=text)

setup.py

@@ -2,7 +2,7 @@
 
 setup(
     name='beets-importreplace',
-    version='0.1',
+    version='0.1.1',
     description='beets plugin to perform replacements on import metadata',
     long_description=open('README.md').read(),
     author='Edgars Supe',

tests/test_importreplace.py

@@ -0,0 +1,56 @@
+import unittest
+
+import beets as beets
+from beets.autotag.hooks import AlbumInfo
+from beets.autotag.hooks import TrackInfo
+from beetsplug.importreplace import ImportReplace
+
+
+class ImportReplaceTest(unittest.TestCase):
+
+    def _create_track_info(self, title: str = None, artist: str = None,
+                           artist_sort: str = None, artist_credit: str = None):
+        return TrackInfo(title=title, artist=artist, artist_sort=artist_sort,
+                         artist_credit=artist_credit)
+
+    def _create_album_info(self, tracks: [TrackInfo] = None, album: str = None,
+                           artist: str = None, artist_sort: str = None,
+                           artist_credit: str = None):
+        return AlbumInfo(tracks=tracks or [], album=album, artist=artist,
+                         artist_sort=artist_sort, artist_credit=artist_credit)
+
+    def _set_config(self, item_fields: [str], album_fields: [str],
+                    replace: {str: str}):
+        beets.config['importreplace']['item_fields'] = item_fields
+        beets.config['importreplace']['album_fields'] = album_fields
+        beets.config['importreplace']['replace'] = replace
+
+    def test_replaces_only_config_fields(self):
+        """Check if plugin replaces text in only the specified fields"""
+        self._set_config(item_fields=['title'], album_fields=['album'],
+                         replace={'a': 'x'})
+        tracks = [self._create_track_info(title='Fao', artist='Bar')]
+        album_info = self._create_album_info(tracks=tracks, album='albumTest',
+                                             artist='Bar')
+        subject = ImportReplace()
+        subject._albuminfo_received(album_info)
+        self.assertEqual(album_info.album, 'xlbumTest')
+        self.assertEqual(album_info.artist, 'Bar')
+        self.assertEqual(album_info.tracks[0].title, 'Fxo')
+        self.assertEqual(album_info.tracks[0].artist, 'Bar')
+
+    def test_handles_empty_fields(self):
+        """Verify that plugin works when field marked for replacement
+         is absent"""
+        self._set_config(item_fields=['title', 'artist'],
+                         album_fields=['album', 'artist'],
+                         replace={'a': 'x'})
+        tracks = [self._create_track_info(title='Fao', artist=None)]
+        album_info = self._create_album_info(tracks=tracks, album='albumTest',
+                                             artist=None)
+        subject = ImportReplace()
+        subject._albuminfo_received(album_info)
+        self.assertEqual(album_info.album, 'xlbumTest')
+        self.assertEqual(album_info.artist, None)
+        self.assertEqual(album_info.tracks[0].title, 'Fxo')
+        self.assertEqual(album_info.tracks[0].artist, None)