revert big changes to step save logic

src/stpipe/step.py

@@ -560,7 +560,37 @@ def run(self, *args):
 
                 # Save the output file if one was specified
                 if not self.skip and self.save_results:
-                    self.save_model(step_result)
+                    # Setup the save list.
+                    if isinstance(step_result, Sequence):
+                        if hasattr(step_result, "save") or isinstance(step_result, str):
+                            results_to_save = [step_result]
+                        else:
+                            results_to_save = step_result
+                    else:
+                        results_to_save = [step_result]
+
+                    for idx, result in enumerate(results_to_save):
+                        if len(results_to_save) <= 1:
+                            idx = None
+                        if isinstance(
+                            result, (AbstractDataModel | AbstractModelLibrary)
+                        ):
+                            self.save_model(result, idx=idx)
+                        elif hasattr(result, "save"):
+                            try:
+                                output_path = self.make_output_path(idx=idx)
+                            except AttributeError:
+                                self.log.warning(
+                                    "`save_results` has been requested, but cannot"
+                                    " determine filename."
+                                )
+                                self.log.warning(
+                                    "Specify an output file with `--output_file` or set"
+                                    " `--save_results=false`"
+                                )
+                            else:
+                                self.log.info("Saving file %s", output_path)
+                                result.save(output_path, overwrite=True)
 
                 if not self.skip:
                     self.log.info("Step %s done", self.name)
@@ -988,39 +1018,18 @@ def save_model(
                     model.shelve(m, i)
             return output_paths
 
-        elif isinstance(model, Sequence) and not isinstance(model, str):
-            if not hasattr(model, "save"):
-                # list of datamodels, e.g. JWST ModelContainer
-                output_paths = []
-                for i, m in enumerate(model):
-                    # ignore list of lists. individual steps should handle this
-                    if not isinstance(m, Sequence):
-                        idx = None if len(model) == 1 else i
-                        output_paths.append(
-                            self.save_model(
-                                m,
-                                idx=idx,
-                                suffix=suffix,
-                                force=force,
-                                **components,
-                            )
-                        )
-                return output_paths
-            else:
-                # JWST SourceModelContainer takes this path
-                save_model_func = partial(
-                    self.save_model,
-                    suffix=suffix,
-                    force=force,
-                    **components,
-                )
-                output_path = model.save(
-                    path=output_file,
-                    save_model_func=save_model_func,
-                )
-                return output_path
-
-        elif hasattr(model, "save"):
+        elif isinstance(model, Sequence):
+            save_model_func = partial(
+                self.save_model,
+                suffix=suffix,
+                force=force,
+                **components,
+            )
+            output_path = model.save(
+                path=output_file,
+                save_model_func=save_model_func,
+            )
+        else:
             # Search for an output file name.
             if self.output_use_model or (
                 output_file is None and not self.search_output_file
@@ -1036,10 +1045,8 @@ def save_model(
                 )
             )
             self.log.info("Saved model in %s", output_path)
-            return output_path
 
-        else:
-            return
+        return output_path
 
     @property
     def make_output_path(self):