Add --no-overlay option

README.md

@@ -103,8 +103,8 @@ usage: ros2nix [-h]
                [--extra-propagated-build-inputs DEP1,DEP2,...]
                [--extra-check-inputs DEP1,DEP2,...]
                [--extra-native-build-inputs DEP1,DEP2,...] [--flake]
-               [--nixfmt] [--compare] [--copyright-holder COPYRIGHT_HOLDER]
-               [--license LICENSE]
+               [--overlay | --no-overlay] [--nixfmt] [--compare]
+               [--copyright-holder COPYRIGHT_HOLDER] [--license LICENSE]
                package.xml [package.xml ...]
 
 positional arguments:
@@ -159,6 +159,8 @@ options:
   --flake               Generate top-level flake.nix instead of default.nix.
                         Use with --fetch if some package.xml files are outside
                         of the flake repo (default: False)
+  --overlay, --no-overlay
+                        Generate overlay.nix (default: True)
   --nixfmt              Format the resulting expressions with nixfmt (default:
                         False)
   --compare             Don't write any file, but check whether writing the

ros2nix/ros2nix.py

@@ -255,6 +255,12 @@ def ros2nix(args):
         help="Generate top-level flake.nix instead of default.nix. "
         "Use with --fetch if some package.xml files are outside of the flake repo",
     )
+    parser.add_argument(
+        "--overlay",
+        action=argparse.BooleanOptionalAction,
+        default=True,
+        help="Generate overlay.nix",
+    )
     parser.add_argument(
         "--nixfmt",
         action="store_true",
@@ -431,6 +437,7 @@ def ros2nix(args):
             err("Failed to write derivation to disk!")
             raise e
 
+    if args.overlay:
         generate_overlay(expressions, args)
 
     if args.flake: