fix: fetch-lib error message showing "Library None not found"

charmcraft/application/commands/store.py

@@ -1534,11 +1534,15 @@ def run(self, parsed_args: argparse.Namespace) -> None:
                     for lib in local_libs_data
                 ]
             )
-        except errors.LibraryError:
-            raise errors.LibraryError(
-                message=f"Library {parsed_args.library} not found in Charmhub.",
-                logpath_report=False,
-            )
+        except errors.LibraryError as e:
+            # If a specific library was requested, use that in the error message
+            # Otherwise, re-raise the original error which should have details
+            if parsed_args.library:
+                raise errors.LibraryError(
+                    message=f"Library {parsed_args.library} not found in Charmhub.",
+                    logpath_report=False,
+                ) from e
+            raise
 
         # check if something needs to be done
         analysis = []
@@ -1559,7 +1563,7 @@ def run(self, parsed_args: argparse.Namespace) -> None:
                     break
             else:
                 raise errors.LibraryError(
-                    message=f"Library {parsed_args.library} not found in Charmhub.",
+                    message=f"Library {lib_data.full_name} not found in Charmhub.",
                     logpath_report=False,
                 )
             emit.debug(f"Store tip: {tip}")

tests/integration/commands/test_store_commands.py

@@ -193,6 +193,34 @@ def test_fetchlib_store_not_found(
     )
 
 
+@pytest.mark.slow
+def test_fetchlib_all_with_not_found(
+    emitter: craft_cli.pytest_plugin.RecordingEmitter,
+    new_path: pathlib.Path,
+    config,
+) -> None:
+    """When running fetch-lib without args and a library is not found, show the library name."""
+    # Create a local library file with a fake lib_id that doesn't exist in Charmhub
+    factory.create_lib_filepath(
+        "testcharm",
+        "testlib",
+        api=0,
+        patch=1,
+        lib_id="fakefakefakefakefakefakefakefake",
+    )
+
+    args = argparse.Namespace(library=None, format=None)
+
+    with pytest.raises(errors.LibraryError) as exc_info:
+        FetchLibCommand(config).run(args)
+
+    # The error message should contain the actual library name, not "None"
+    assert "charms.testcharm.v0.testlib" in exc_info.value.args[0]
+    assert exc_info.value.args[0] == (
+        "Library charms.testcharm.v0.testlib not found in Charmhub."
+    )
+
+
 @pytest.mark.slow
 @pytest.mark.parametrize("formatted", [None, "json"])
 def test_fetchlib_store_is_old(