Also report library blocks.

Those are needed for recursive tracing of dependencies.

blender_asset_tracer/tracer/__init__.py

@@ -8,7 +8,6 @@ from . import result, block_walkers
 log = logging.getLogger(__name__)
 
 codes_to_skip = {
-    b'LI',  # Library blocks we handle after the blend file itself.
     b'ID', b'WM', b'SN',  # These blocks never have external assets.
 }
 

blender_asset_tracer/tracer/block_walkers.py

@@ -69,6 +69,16 @@ def _from_block_im(block: blendfile.BlendFileBlock) -> typing.Iterator[result.Bl
     yield result.BlockUsage(block, pathname, is_sequence, path_full_field=field)
 
 
+def _from_block_li(block: blendfile.BlendFileBlock) -> typing.Iterator[result.BlockUsage]:
+    """Library data blocks."""
+    path, field = block.get(b'name', return_field=True)
+    yield result.BlockUsage(block, path, path_full_field=field)
+
+    # The 'filepath' also points to the blend file. However, this is set to the
+    # absolute path of the file by Blender (see BKE_library_filepath_set). This
+    # is thus not a property we have to report or rewrite.
+
+
 def _from_block_me(block: blendfile.BlendFileBlock) -> typing.Iterator[result.BlockUsage]:
     """Mesh data blocks."""
     block_external = block.get_pointer((b'ldata', b'external'), None)