fix(fetchart): sources definition

beets/util/config.py

@@ -27,13 +27,16 @@ def sanitize_choices(
 
 
 def sanitize_pairs(
-    pairs: Sequence[tuple[str, str]], pairs_all: Sequence[tuple[str, str]]
+    pairs: Sequence[tuple[str, str]],
+    pairs_all: Sequence[tuple[str, str]],
+    raise_on_unknown: bool = False,
 ) -> list[tuple[str, str]]:
     """Clean up a single-element mapping configuration attribute as returned
     by Confuse's `Pairs` template: keep only two-element tuples present in
     pairs_all, remove duplicate elements, expand ('str', '*') and ('*', '*')
     wildcards while keeping the original order. Note that ('*', '*') and
     ('*', 'whatever') have the same effect.
+    Set raise_on_unknown to raise an error when a provided pair is not recognised
 
     For example,
 
@@ -61,6 +64,17 @@ def sanitize_pairs(
                 res.extend(new)
             elif v == "*":
                 new = [o for o in others if o not in seen and o[0] == k]
+
+                if len(new) == 0 and raise_on_unknown:
+                    raise UnknownPairError(k, v)
+
                 seen.update(new)
                 res.extend(new)
+            elif raise_on_unknown:
+                raise UnknownPairError(k, v)
     return res
+
+
+class UnknownPairError(Exception):
+    def __init__(self, k, v):
+        super().__init__(f"setting {k}={v} is not recognized")

beetsplug/fetchart.py

@@ -33,7 +33,7 @@
 from beets.util import bytestring_path, get_temp_filename, sorted_walk, syspath
 from beets.util.artresizer import ArtResizer
 from beets.util.color import colorize
-from beets.util.config import sanitize_pairs
+from beets.util.config import UnknownPairError, sanitize_pairs
 
 if TYPE_CHECKING:
     from collections.abc import Iterable, Iterator, Sequence
@@ -1407,16 +1407,7 @@ def __init__(self) -> None:
             self.import_stages = [self.fetch_art]
             self.register_listener("import_task_files", self.assign_art)
 
-        available_sources = [
-            (s_cls.ID, c)
-            for s_cls in ART_SOURCES
-            if s_cls.available(self._log, self.config)
-            for c in s_cls.VALID_MATCHING_CRITERIA
-        ]
-        sources = sanitize_pairs(
-            self.config["sources"].as_pairs(default_value="*"),
-            available_sources,
-        )
+        sources = self._get_sources()
 
         if "remote_priority" in self.config:
             self._log.warning(
@@ -1441,6 +1432,33 @@ def __init__(self) -> None:
             for s, c in sources
         ]
 
+    def _get_sources(self) -> list[tuple[str, str]]:
+        available_sources = [
+            (s_cls.ID, c)
+            for s_cls in ART_SOURCES
+            if s_cls.available(self._log, self.config)
+            for c in s_cls.VALID_MATCHING_CRITERIA
+        ]
+
+        if isinstance(self.config["sources"].get(), str):
+            cfg_sources = [(self.config["sources"].get(), "*")]
+        else:
+            cfg_sources = self.config["sources"].as_pairs(default_value="*")
+
+        try:
+            sources = sanitize_pairs(
+                cfg_sources,
+                available_sources,
+                raise_on_unknown=True,
+            )
+
+            if len(sources) == 0:
+                raise ui.UserError("fetchart: no sources defined in config")
+
+            return sources
+        except UnknownPairError as e:
+            raise ui.UserError(e)
+
     @staticmethod
     def _is_source_file_removal_enabled() -> bool:
         return config["import"]["delete"].get(bool) or config["import"][

docs/changelog.rst

@@ -37,6 +37,8 @@ New features
   :bug:`5698`
 - :doc:`plugins/replaygain`: Conflicting replay gain tags are now removed on
   write. RG_* tags are removed when setting R128_* and vice versa.
+- :doc:`plugins/fetchart`: Error when a configured source does not exist or
+  sources configuration is empty.
 
 Bug fixes
 ~~~~~~~~~

test/plugins/test_fetchart.py

@@ -19,6 +19,7 @@
 
 from beets import util
 from beets.test.helper import IOMixin, PluginTestCase
+from beetsplug.fetchart import FetchArtPlugin, FileSystem
 
 
 class FetchartCliTest(IOMixin, PluginTestCase):
@@ -103,3 +104,26 @@ def test_colorization(self):
         self.config["ui"]["color"] = True
         out = self.run_with_output("fetchart")
         assert " - the älbum: \x1b[1;31mno art found\x1b[39;49;00m\n" == out
+
+    def test_sources_is_a_string(self):
+        self.config["fetchart"].set({"sources": "filesystem"})
+        fa = FetchArtPlugin()
+        assert len(fa.sources) == 1
+        assert isinstance(fa.sources[0], FileSystem)
+
+    def test_sources_is_an_asterisk(self):
+        self.config["fetchart"].set({"sources": "*"})
+        fa = FetchArtPlugin()
+        assert len(fa.sources) == 10
+
+    def test_sources_is_a_string_list(self):
+        self.config["fetchart"].set({"sources": ["filesystem", "coverart"]})
+        fa = FetchArtPlugin()
+        assert len(fa.sources) == 3
+
+    def test_sources_is_a_mapping_list(self):
+        self.config["fetchart"].set(
+            {"sources": {"filesystem": "*", "coverart": "*"}}
+        )
+        fa = FetchArtPlugin()
+        assert len(fa.sources) == 3

test/util/test_config.py

@@ -1,6 +1,6 @@
 import pytest
 
-from beets.util.config import sanitize_choices, sanitize_pairs
+from beets.util.config import UnknownPairError, sanitize_choices, sanitize_pairs
 
 
 @pytest.mark.parametrize(
@@ -36,3 +36,17 @@ def test_sanitize_pairs():
         ("key", "value"),
         ("foo", "foobar"),
     ]
+
+
+def test_sanitize_pairs_unknown_key():
+    with pytest.raises(UnknownPairError):
+        sanitize_pairs(
+            [("bar", "foo")], [("key", "value")], raise_on_unknown=True
+        )
+
+
+def test_sanitize_pairs_unknown_key_wildcard_value():
+    with pytest.raises(UnknownPairError):
+        sanitize_pairs(
+            [("foo", "*")], [("key", "value")], raise_on_unknown=True
+        )