nix_eval: add --json by default

pkgs/clan-cli/clan_cli/config/__init__.py

@@ -100,7 +100,6 @@ def options_for_machine(machine_name: str, flake: Optional[Path] = None) -> dict
     proc = subprocess.run(
         nix_eval(
             flags=[
-                "--json",
                 "--show-trace",
                 "--impure",
                 "--expr",
@@ -138,7 +137,6 @@ def read_machine_option_value(machine_name: str, option: str) -> str:
     proc = subprocess.run(
         nix_eval(
             flags=[
-                "--json",
                 "--show-trace",
                 "--extra-experimental-features",
                 "nix-command flakes",

pkgs/clan-cli/clan_cli/config/machine.py

@@ -45,7 +45,6 @@ def schema_for_machine(machine_name: str, flake: Optional[Path] = None) -> dict:
     proc = subprocess.run(
         nix_eval(
             flags=[
-                "--json",
                 "--impure",
                 "--show-trace",
                 "--extra-experimental-features",

pkgs/clan-cli/clan_cli/nix.py

@@ -41,14 +41,19 @@ def nix_build_machine(
 
 
 def nix_eval(flags: list[str]) -> list[str]:
-    if os.environ.get("IN_NIX_SANDBOX"):
+    default_flags = [
-        with tempfile.TemporaryDirectory() as nix_store:
-            return [
         "nix",
         "eval",
         "--show-trace",
+        "--json",
         "--extra-experimental-features",
         "nix-command flakes",
+    ]
+    if os.environ.get("IN_NIX_SANDBOX"):
+        with tempfile.TemporaryDirectory() as nix_store:
+            return (
+                default_flags
+                + [
                     "--override-input",
                     "nixpkgs",
                     str(nixpkgs_source()),
@@ -56,14 +61,10 @@ def nix_eval(flags: list[str]) -> list[str]:
                     # error: cannot unlink '/nix/store/6xg259477c90a229xwmb53pdfkn6ig3g-default-builder.sh': Operation not permitted
                     "--store",
                     nix_store,
-            ] + flags
+                ]
-    return [
+                + flags
-        "nix",
+            )
-        "eval",
+    return default_flags + flags
-        "--show-trace",
-        "--extra-experimental-features",
-        "nix-command flakes",
-    ] + flags
 
 
 def nix_shell(packages: list[str], cmd: list[str]) -> list[str]: