Make wrap_snap_operations return the actual error.

lib/charms/operator_libs_linux/v2/snap.py

@@ -1288,10 +1288,10 @@ def _wrap_snap_operations(
             snaps.append(snap)
         except SnapError as e:  # noqa: PERF203
             logger.warning("Failed to %s snap %s: %s!", op, s, e.message)
-            errors.append(s)
+            errors.append(e.message)
         except SnapNotFoundError:
             logger.warning("Snap '%s' not found in cache!", s)
-            errors.append(s)
+            errors.append(f"Snap '{s}' not found in cache!")
 
     if errors:
         raise SnapError(f"Failed to install or refresh snap(s): {', '.join(errors)}")

tests/unit/test_snap.py

@@ -1095,7 +1095,10 @@ def __getitem__(self, name: str) -> snap.Snap:
                 snap.add("nothere")
         repr(ctx.exception)  # ensure custom __repr__ doesn't error
         self.assertEqual("<charms.operator_libs_linux.v2.snap.SnapError>", ctx.exception.name)
-        self.assertIn("Failed to install or refresh snap(s): nothere", ctx.exception.message)
+        self.assertIn(
+            "Failed to install or refresh snap(s): Snap 'nothere' not found in cache!",
+            ctx.exception.message,
+        )
 
     def test_snap_get(self):
         """Test the multiple different ways of calling the Snap.get function.