POC to allow alias

Author: Erotemic

jsonargparse/actions.py

@@ -69,8 +69,11 @@ def _find_action_and_subcommand(
     if exclude is not None:
         actions = [a for a in actions if not isinstance(a, exclude)]
     fallback_action = None
+
+    ALLOW_ALIAS = True
+
     for action in actions:
-        if action.dest == dest:
+        if action.dest == dest or (ALLOW_ALIAS and dest in get_alias_dest(action)):
             if isinstance(action, _ActionConfigLoad):
                 fallback_action = action
             else:
@@ -746,3 +749,11 @@ def handle_subcommands(
             # Handle inner subcommands
             if subparser._subparsers is not None:
                 _ActionSubCommands.handle_subcommands(subparser, cfg, env, defaults, key+'.', fail_no_subcommand=fail_no_subcommand)
+
+
+def get_alias_dest(action):
+    def option_string_to_var(optstr):
+        " normalize a cli key as a variable "
+        return optstr.lstrip('-').replace('-', '_')
+
+    return [option_string_to_var(optstr) for optstr in action.option_strings]

jsonargparse/core.py

@@ -1254,7 +1254,25 @@ def _apply_actions(
                 continue
 
             action_dest = action.dest if subcommand is None else subcommand+'.'+action.dest
-            value = cfg[action_dest]
+            ALLOW_ALIAS = 1
+            try:
+                value = cfg[action_dest]
+            except KeyError:
+                from jsonargparse.actions import get_alias_dest
+                if ALLOW_ALIAS:
+                    # If the main key isn't in the config, check if it exists
+                    # under an alias.
+                    found = None
+                    for alias in get_alias_dest(action):
+                        if alias in cfg:
+                            value = cfg[alias]
+                            found = True
+                            break
+                    if not found:
+                        raise
+                else:
+                    raise
+                    ...
             if skip_fn and skip_fn(value):
                 continue
             with parser_context(parent_parser=self, lenient_check=True):