fix: Empty source tables causing errors when runing pdm (#2043)

news/2034.bugfix.md

@@ -0,0 +1 @@
+Fix a bug that empty source tables in configuration files causes errors when running pdm commands.

src/pdm/project/config.py

@@ -260,7 +260,7 @@ def self_data(self) -> dict[str, Any]:
 
     def iter_sources(self) -> Iterator[RepositoryConfig]:
         for name, data in self._data.items():
-            if name.startswith(f"{SOURCE}.") and name not in self._config_map:
+            if name.startswith(f"{SOURCE}.") and name not in self._config_map and data:
                 yield RepositoryConfig(**data, name=name[len(SOURCE) + 1 :], config_prefix=SOURCE)
 
     def _save_config(self) -> None:

src/pdm/project/core.py

@@ -380,7 +380,7 @@ def merge_sources(other_sources: Iterable[RepositoryConfig]) -> None:
             merge_sources(self.project_config.iter_sources())
             merge_sources(self.global_config.iter_sources())
         for source in result.values():
-            assert source.url, "Source URL must not be empty"
+            assert source.url, f"Source URL must not be empty for {source.name}"
             source.url = expand_env_vars_in_auth(source.url)
         return list(result.values())