Replace add_class_choices with set_choices

pytorch_lightning/utilities/cli.py

@@ -77,7 +77,7 @@ def __str__(self) -> str:
 
 
 OPTIMIZER_REGISTRY = _Registry()
-OPTIMIZER_REGISTRY.register_package(torch.optim, torch.optim.Optimizer)
+OPTIMIZER_REGISTRY.register_package(torch.optim, Optimizer)
 
 LR_SCHEDULER_REGISTRY = _Registry()
 LR_SCHEDULER_REGISTRY.register_package(torch.optim.lr_scheduler, torch.optim.lr_scheduler._LRScheduler)
@@ -86,6 +86,9 @@ def __str__(self) -> str:
 class LightningArgumentParser(ArgumentParser):
     """Extension of jsonargparse's ArgumentParser for pytorch-lightning."""
 
+    # use class attribute because `parse_args` is only called on the main parser
+    _choices: Dict[str, Tuple[Type, ...]] = {}
+
     def __init__(self, *args: Any, parse_as_dict: bool = True, **kwargs: Any) -> None:
         """Initialize argument parser that supports configuration file input.
 
@@ -105,8 +108,6 @@ def __init__(self, *args: Any, parse_as_dict: bool = True, **kwargs: Any) -> Non
         # separate optimizers and lr schedulers to know which were added
         self._optimizers: Dict[str, Tuple[Union[Type, Tuple[Type, ...]], str]] = {}
         self._lr_schedulers: Dict[str, Tuple[Union[Type, Tuple[Type, ...]], str]] = {}
-        # we need a mutable global argv copy in order to support `add_class_choices`
-        sys.__argv = sys.argv.copy()
 
     def add_lightning_class_args(
         self,
@@ -167,7 +168,8 @@ def add_optimizer_args(
             assert issubclass(optimizer_class, Optimizer)
         kwargs = {"instantiate": False, "fail_untyped": False, "skip": {"params"}}
         if isinstance(optimizer_class, tuple):
-            self.add_class_choices(optimizer_class, nested_key, **kwargs)
+            self.add_subclass_arguments(optimizer_class, nested_key, **kwargs)
+            self.set_choices(nested_key, optimizer_class)
         else:
             self.add_class_arguments(optimizer_class, nested_key, **kwargs)
         self._optimizers[nested_key] = (optimizer_class, link_to)
@@ -191,33 +193,32 @@ def add_lr_scheduler_args(
             assert issubclass(lr_scheduler_class, LRSchedulerTypeTuple)
         kwargs = {"instantiate": False, "fail_untyped": False, "skip": {"optimizer"}}
         if isinstance(lr_scheduler_class, tuple):
-            self.add_class_choices(lr_scheduler_class, nested_key, **kwargs)
+            self.add_subclass_arguments(lr_scheduler_class, nested_key, **kwargs)
+            self.set_choices(nested_key, lr_scheduler_class)
         else:
             self.add_class_arguments(lr_scheduler_class, nested_key, **kwargs)
         self._lr_schedulers[nested_key] = (lr_scheduler_class, link_to)
 
     def parse_args(self, *args: Any, **kwargs: Any) -> Dict[str, Any]:
-        with mock.patch("sys.argv", sys.__argv):
+        argv = sys.argv
+        for k, classes in self._choices.items():
+            if not any(arg.startswith(f"--{k}") for arg in argv):
+                # the key wasn't passed - maybe defined in a config, maybe it's optional
+                continue
+            argv = self._convert_argv_issue_84(classes, k, argv)
+        self._choices.clear()
+        with mock.patch("sys.argv", argv):
             return super().parse_args(*args, **kwargs)
 
-    def add_class_choices(self, classes: Tuple[Type, ...], nested_key: str, *args: Any, **kwargs: Any) -> None:
+    def set_choices(self, nested_key: str, classes: Tuple[Type, ...]) -> None:
+        self._choices[nested_key] = classes
+
+    @staticmethod
+    def _convert_argv_issue_84(classes: Tuple[Type, ...], nested_key: str, argv: List[str]) -> List[str]:
         """Placeholder for https://github.com/omni-us/jsonargparse/issues/84.
 
         This should be removed once implemented.
         """
-        if not any(arg.startswith(f"--{nested_key}") for arg in sys.__argv):  # the key was passed
-            if any(arg.startswith("--config") for arg in sys.__argv):  # a config was passed
-                # parsing config files would be too difficult, fall back to what's available
-                self.add_subclass_arguments(classes, nested_key, *args, **kwargs)
-            elif kwargs.get("required", False):
-                raise MisconfigurationException(f"The {nested_key} key is required but wasn't passed")
-        else:
-            clean_argv = self._convert_argv_issue_84(classes, nested_key, sys.__argv)
-            self.add_subclass_arguments(classes, nested_key, *args, **kwargs)
-            sys.__argv = clean_argv
-
-    @staticmethod
-    def _convert_argv_issue_84(classes: Tuple[Type, ...], nested_key: str, argv: List[str]) -> List[str]:
         passed_args, clean_argv = {}, []
         argv_key = f"--{nested_key}"
         # get the argv args for this nested key