testing: migrate flakes/flakes.sh (part 8)

eval-system influences attribute choice

Change-Id: I02d611ed17748c73d5c77ebd0a44f558ab63d1c8

tests/functional/flakes/flakes.sh

@@ -96,11 +96,6 @@ nix build -o $TEST_ROOT/result git+file://$flake1Dir
 nix build -o $flake1Dir/result git+file://$flake1Dir
 nix path-info $flake1Dir/result
 
-# Ensure that eval-system affects the chosen attribute
-cp -r "$flake1Dir" "$flake1Dir.kittified"
-sed -i "s#$system#kitty-kitty#" "$flake1Dir.kittified/flake.nix"
-nix build --eval-system kitty-kitty "$flake1Dir.kittified"
-
 # 'getFlake' on an unlocked flakeref should fail in pure mode, but
 # succeed in impure mode.
 (! nix build -o $TEST_ROOT/result --expr "(builtins.getFlake \"$flake1Dir\").packages.$system.default")

tests/functional2/flakes/test_cli.py

@@ -166,6 +166,13 @@ class TestAttrMatch:
             assert "-simple.drv" in path
 
 
+def test_eval_system_takes_effect(nix: Nix, flake1: Path):
+    (flake1 / "flake.nix").write_text(
+        (flake1 / "flake.nix").read_text().replace(system, "kitty-kitty")
+    )
+    nix.nix(["build", "--eval-system", "kitty-kitty", flake1]).run().ok()
+
+
 @pytest.mark.usefixtures("registry")
 class TestRegistry:
     def test_registry_list(self, nix: Nix):