1 files changed, 47 insertions, 0 deletions
diff --git a/tests/test_path.py b/tests/test_path.py
new file mode 100644
index 0000000..a9e826e
--- /dev/null
+++ b/tests/test_path.py
@@ -0,0 +1,47 @@
+from typing import cast
+
+import pytest
+
+from debputy.exceptions import SymlinkLoopError
+from debputy.filesystem_scan import VirtualPathBase
+from debputy.plugin.api import virtual_path_def
+from debputy.plugin.api.test_api import build_virtual_file_system
+
+
+def test_symlink_lookup() -> None:
+    fs = build_virtual_file_system(
+        [
+            virtual_path_def("./usr/share/doc/bar", link_target="foo"),
+            "./usr/share/doc/foo/copyright",
+            virtual_path_def("./usr/share/bar/data", link_target="../foo/data"),
+            "./usr/share/foo/data/foo.dat",
+            virtual_path_def("./usr/share/baz/data", link_target="/usr/share/foo/data"),
+            virtual_path_def(
+                "./usr/share/test/loop-a", link_target="/usr/share/test/loop-b"
+            ),
+            virtual_path_def("./usr/share/test/loop-b", link_target="./loop-c"),
+            virtual_path_def("./usr/share/test/loop-c", link_target="../test/loop-a"),
+        ]
+    )
+    assert fs.lookup("/usr/share/doc/bar/copyright") is not None
+    assert fs.lookup("/usr/share/bar/data/foo.dat") is not None
+    assert fs.lookup("/usr/share/baz/data/foo.dat") is not None
+
+    vp_fs: VirtualPathBase = cast("VirtualPathBase", fs)
+    p, missing = vp_fs.attempt_lookup("/usr/share/doc/foo/non-existent")
+    assert p.path == "./usr/share/doc/foo"
+    assert missing == ["non-existent"]
+
+    p, missing = vp_fs.attempt_lookup("/usr/share/bar/data/non-existent")
+    assert p.path == "./usr/share/foo/data"
+    assert missing == ["non-existent"]
+
+    p, missing = vp_fs.attempt_lookup("/usr/share/baz/data/non-existent")
+    assert p.path == "./usr/share/foo/data"
+    assert missing == ["non-existent"]
+
+    # The symlink can be looked up
+    assert fs.lookup("./usr/share/test/loop-a") is not None
+    with pytest.raises(SymlinkLoopError):
+        # But resolving it will cause issues
+        fs.lookup("./usr/share/test/loop-a/")