manifest: Use faster yaml CLoader if available

src/west/commands.py

@@ -22,6 +22,12 @@
 
 import colorama
 import pykwalify
+
+try:
+    from yaml import CSafeLoader as SafeLoader
+except ImportError:
+    from yaml import SafeLoader  # type: ignore
+
 import yaml
 
 from west.configuration import Configuration
@@ -649,7 +655,7 @@ def _ext_specs(project):
         # Load the spec file and check the schema.
         with open(spec_file) as f:
             try:
-                commands_spec = yaml.safe_load(f.read())
+                commands_spec = yaml.load(f.read(), Loader=SafeLoader)
             except yaml.YAMLError as e:
                 raise ExtensionCommandError from e
         try:

src/west/manifest.py

@@ -22,6 +22,12 @@
 
 import pykwalify.core
 import yaml
+
+try:
+    from yaml import CSafeLoader as SafeLoader
+except ImportError:
+    from yaml import SafeLoader  # type: ignore
+
 from packaging.version import parse as parse_version
 
 from west import util
@@ -204,7 +210,7 @@ def _is_yml(path: PathType) -> bool:
 
 def _load(data: str) -> Any:
     try:
-        return yaml.safe_load(data)
+        return yaml.load(data, Loader=SafeLoader)
     except yaml.scanner.ScannerError as e:
         raise MalformedManifest(data) from e