allow IFD in nix flake show

Signed-off-by: ahuston-0 <aliceghuston@gmail.com>

flupdt/cli.py

@@ -21,6 +21,11 @@ def parse_inputs() -> argparse.Namespace:
         action="store_true",
         help="whether to compare two drv sets, must provide two evaluation jsons to compare",
     )
+    parser.add_argument(
+        "--allow-import-from-derivation",
+        action="store_true",
+        help="whether to allow IFD during certain actions (ex. nix flake show)",
+    )
     parser.add_argument(
         "--compare-pre-json",
         metavar="pre-json-path",

flupdt/flake_show.py

@@ -71,7 +71,7 @@ def get_derivations_from_check(nix_path: str, path_to_flake: str) -> list[str]:
     return derivations
 
 
-def get_derivations(path_to_flake: str) -> list[str]:
+def get_derivations(path_to_flake: str, *, allow_import_from_derivation: False = False) -> list[str]:
     """Gets all derivations present in a flake.
 
     :param path_to_flake: path to flake to be checked
@@ -83,7 +83,9 @@ def get_derivations(path_to_flake: str) -> list[str]:
     if nix_path is None:
         status_msg = "nix is not available in the PATH, please verify that it is installed"
         raise RuntimeError(status_msg)
-    flake_show = bash_wrapper(f"{nix_path} flake show --json --accept-flake-path", path=path_to_flake)
+    cmd = f"{nix_path} flake show --json --accept-flake-path"
+    cmd += " --allow-import-from-derivation" if allow_import_from_derivation else ""
+    flake_show = bash_wrapper(cmd, path=path_to_flake)
     if flake_show[2] != 0:
         logger.error("flake show returned non-zero exit code")
         logger.warning("falling back to full evaluation via nix flake check")

flupdt/main.py

@@ -99,7 +99,7 @@ def build_or_eval(args: Namespace) -> None:
     """
     flake_path = args.flake_path
     derivations, hydra_jobs = partition(
-        lambda s: s.startswith("hydraJobs"), get_derivations(flake_path)
+        lambda s: s.startswith("hydraJobs"), get_derivations(flake_path, args["allow-import-from-derivation"])
     )
     derivations, hydra_jobs = list(derivations), list(hydra_jobs)
     logger.info(f"derivations: {list(derivations)}")