testing: migrates flakes/subdir-flake.sh

Change-Id: I9ac02056d490473dd751f7ec7857840290f5afc5

tests/functional2/flakes/test_subdir_flake.py

@@ -0,0 +1,24 @@
+from fnmatch import fnmatch
+from testlib.fixtures.git import Git
+from testlib.fixtures.nix import Nix
+from testlib.fixtures.file_helper import with_files
+from testlib.utils import get_global_asset_pack
+from pathlib import Path
+from .common import simple_flake
+
+
+@with_files({"flake-container": get_global_asset_pack(".git") | {"flake-dir": simple_flake()}})
+def test_subdir_flake(nix: Nix, files: Path, git: Git):
+    container = files / "flake-container"
+    flake = container / "flake-dir"
+
+    nix.settings.add_xp_feature("nix-command", "flakes")
+
+    git(container, "add", "flake-dir")
+
+    info = nix.nix(["flake", "info", "--json"], cwd=flake).run().json()
+
+    assert fnmatch(info["resolvedUrl"], "git+file://*/flake-container[?]dir=flake-dir")
+    assert fnmatch(info["url"], "git+file://*/flake-container[?]dir=flake-dir")
+
+    nix.nix(["build", f"path:{flake}#foo", "-L"]).run().ok()