Feature proposal: Add --profile for conditional config

aider/args.py

@@ -19,6 +19,19 @@
 from .dump import dump  # noqa: F401
 
 
+class YAMLConfigFileParserIgnoreProfiles(configargparse.YAMLConfigFileParser):
+    """
+    A custom YAMLConfigFileParser that removes the top-level 'profiles' key from its result. We use
+    this to avoid having to set ignore_unknown_config_file_keys=True on our
+    configargparse.ArgumentParser, which would fail to flag invalid config keys to the user.
+    """
+
+    def parse(self, stream):
+        result = super().parse(stream)
+        result.pop("profiles", None)
+        return result
+
+
 def resolve_aiderignore_path(path_str, git_root=None):
     path = Path(path_str)
     if path.is_absolute():
@@ -37,7 +50,7 @@ def get_parser(default_config_files, git_root):
         description="aider is AI pair programming in your terminal",
         add_config_file_help=True,
         default_config_files=default_config_files,
-        config_file_parser_class=configargparse.YAMLConfigFileParser,
+        config_file_parser_class=YAMLConfigFileParserIgnoreProfiles,
         auto_env_var_prefix="AIDER_",
     )
     # List of valid edit formats for argparse validation & shtab completion.
@@ -129,6 +142,11 @@ def get_parser(default_config_files, git_root):
         default=".aider.model.metadata.json",
         help="Specify a file with context window and costs for unknown models",
     ).complete = shtab.FILE
+    group.add_argument(
+        "--profile",
+        metavar="PROFILE",
+        help="Include settings from a named profile in the 'profiles' section of the config",
+    )
     group.add_argument(
         "--alias",
         action="append",

aider/main.py

@@ -15,6 +15,7 @@
 
 import importlib_resources
 import shtab
+import yaml
 from dotenv import load_dotenv
 from prompt_toolkit.enums import EditingMode
 
@@ -332,6 +333,16 @@ def generate_search_path_list(default_file, git_root, command_line_file):
     return files
 
 
+def load_profiles_from_config_files(config_files):
+    profiles = {}
+    for config_file in config_files:
+        if Path(config_file).exists():
+            with open(config_file, "r") as f:
+                config = yaml.safe_load(f) or {}
+            profiles.update(config.get("profiles", {}))
+    return profiles
+
+
 def register_models(git_root, model_settings_fname, io, verbose=False):
     model_settings_files = generate_search_path_list(
         ".aider.model.settings.yml", git_root, model_settings_fname
@@ -497,6 +508,31 @@ def main(argv=None, input=None, output=None, force_git_root=None, return_coder=F
 
     args, unknown = parser.parse_known_args(argv)
 
+    # Include config from --profile
+    #   - Do this early so profiles can contain settings like --env-file, and cli args override
+    #     profile settings
+    if args.profile is not None:
+        profiles = load_profiles_from_config_files(default_config_files)
+        profile = profiles.get(args.profile)
+        if not profile:
+            print(f"Profile not found: {args.profile}", file=sys.stderr)
+            print(f"Available profiles: {", ".join(profiles.keys())}", file=sys.stderr)
+            return 1
+        if args.verbose:
+            print(f"Using profile: {args.profile}")
+        profile_argv = []
+        for k, v in profile.items():
+            if v is None:
+                v = ""
+            if isinstance(v, bool):
+                profile_argv.append(f"--{k if v else f'no-{k}'}")
+            else:
+                profile_argv.append(f"--{k}={v}")
+        # Inject profile settings into argv (used here and below)
+        argv = profile_argv + argv
+        # Parse again with settings from profile
+        args, unknown = parser.parse_known_args(argv)
+
     # Load the .env file specified in the arguments
     loaded_dotenvs = load_dotenv_files(git_root, args.env_file, args.encoding)