fix: load global config tree from config file instead of local subtree

Author: jaisw7

examples/train_config.yml

@@ -1,2 +1,3 @@
-epochs: 200
-lr: 0.002
+train:
+    epochs: 200
+    lr: 0.002

src/nanocli/core.py

@@ -197,9 +197,20 @@ def _execute(self, args: list[str]) -> None:
                     current._show_command_help(console, part, schema)
                     return
 
-                # Get cfg file
+                # Get cfg file - load global tree and extract subtree
                 cfg_file = flags["cfg"]
-                base = load_yaml(cfg_file) if cfg_file else None
+                base = None
+                if cfg_file:
+                    global_cfg = load_yaml(cfg_file)
+                    # Extract subtree based on consumed path
+                    base = global_cfg
+                    for path_key in consumed_path:
+                        if hasattr(base, path_key) or (isinstance(base, dict) and path_key in base):
+                            base = base[path_key]
+                        else:
+                            # Path doesn't exist in config, use None
+                            base = None
+                            break
 
                 # Compile config
                 if schema:

tests/test_core.py

@@ -402,8 +402,9 @@ def test_config_with_yaml(self, tmp_path: Path):
         def train(cfg: SimpleConfig):
             print(f"Training {cfg.name}")
 
+        # Global tree structure - train subtree will be extracted
         yaml_file = tmp_path / "config.yml"
-        yaml_file.write_text("name: from_yaml\ncount: 42")
+        yaml_file.write_text("train:\n  name: from_yaml\n  count: 42")
 
         old_stdout = sys.stdout
         sys.stdout = io.StringIO()
@@ -622,8 +623,9 @@ def test_print_with_yaml_file(self, tmp_path: Path):
         def train(cfg: SimpleConfig):
             pass
 
+        # Global tree structure
         yaml_file = tmp_path / "config.yml"
-        yaml_file.write_text("name: yaml_test\ncount: 99")
+        yaml_file.write_text("train:\n  name: yaml_test\n  count: 99")
 
         old_stdout = sys.stdout
         sys.stdout = io.StringIO()