fix: overload merge to automatically merge pack extras too

beet/library/base.py

@@ -30,6 +30,7 @@
     Iterator,
     List,
     Mapping,
+    MutableMapping,
     Optional,
     Protocol,
     Tuple,
@@ -40,7 +41,14 @@
 )
 from zipfile import ZipFile
 
-from beet.core.container import Container, ContainerProxy, MatchMixin, MergeMixin, Pin
+from beet.core.container import (
+    Container,
+    ContainerProxy,
+    MatchMixin,
+    MergeMixin,
+    Pin,
+    SupportsMerge,
+)
 from beet.core.file import File, FileOrigin, JsonFile, PngFile
 from beet.core.utils import FileSystemPath, JsonDict, TextComponent, extra_field
 
@@ -50,6 +58,7 @@
 PackFileType = TypeVar("PackFileType", bound="PackFile")
 NamespaceType = TypeVar("NamespaceType", bound="Namespace")
 NamespaceFileType = TypeVar("NamespaceFileType", bound="NamespaceFile")
+MergeableType = TypeVar("MergeableType", bound=SupportsMerge)
 
 PackFile = File[Any, Any]
 
@@ -364,6 +373,22 @@ def process(self, key: str, value: NamespaceType) -> NamespaceType:
     def missing(self, key: str) -> NamespaceType:
         return self.namespace_type()
 
+    @overload
+    def merge(self: T, other: T) -> bool:
+        ...
+
+    @overload
+    def merge(
+        self: MutableMapping[T, MergeableType], other: Mapping[T, MergeableType]
+    ) -> bool:
+        ...
+
+    def merge(self, other: Any) -> bool:
+        super().merge(other)  # type: ignore
+        if isinstance(other, Pack):
+            self.extra.merge(other.extra)
+        return True
+
     @property
     def content(self) -> Iterator[Tuple[str, NamespaceFile]]:
         """Iterator that yields all the files stored in the pack."""

beet/toolchain/helpers.py

@@ -61,10 +61,7 @@ def plugin(ctx: Context):
         with child_ctx.activate() as pipeline:
             pipeline.run(specs)
 
-        ctx.assets.extra.merge(child_ctx.assets.extra)
         ctx.assets.merge(child_ctx.assets)
-
-        ctx.data.extra.merge(child_ctx.data.extra)
         ctx.data.merge(child_ctx.data)
 
     return plugin

beet/toolchain/project.py

@@ -293,8 +293,5 @@ def __call__(self, ctx: Context):
         if child_ctx.output_directory:
             return
 
-        ctx.assets.extra.merge(child_ctx.assets.extra)
         ctx.assets.merge(child_ctx.assets)
-
-        ctx.data.extra.merge(child_ctx.data.extra)
         ctx.data.merge(child_ctx.data)

tests/test_data_pack.py

@@ -169,6 +169,13 @@ def test_merge_block_tags():
     }
 
 
+def test_merge_extra():
+    pack = DataPack()
+    pack.merge(DataPack(description="hello", pack_format=88))
+    assert pack.description == "hello"
+    assert pack.pack_format == 88
+
+
 def test_match():
     pack = DataPack()
     custom = pack["custom"]