Rename `libmount` to `filesystem`

1 files changed, 143 insertions, 0 deletions

diff --git a/tests/test_filesystem.py b/tests/test_filesystem.py
new file mode 100644
index 0000000..b33322c
--- /dev/null
+++ b/tests/test_filesystem.py
@@ -0,0 +1,143 @@
+from concurrent.futures import ThreadPoolExecutor
+from contextlib import contextmanager, suppress
+from pathlib import Path
+from shutil import rmtree
+from unittest import TestCase
+from uuid import uuid4
+
+from snekbox.filesystem import UnmountFlags, mount, unmount
+
+
+class LibMountTests(TestCase):
+    temp_dir = Path("/tmp/snekbox")
+
+    @classmethod
+    def setUpClass(cls):
+        cls.temp_dir.mkdir(exist_ok=True, parents=True)
+
+    @classmethod
+    def tearDownClass(cls):
+        rmtree(cls.temp_dir, ignore_errors=True)
+
+    @contextmanager
+    def get_mount(self):
+        """Yield a valid mount point and unmount after context."""
+        path = self.temp_dir / str(uuid4())
+        path.mkdir()
+        try:
+            mount(source="", target=path, fs="tmpfs")
+            yield path
+        finally:
+            with suppress(OSError):
+                unmount(path)
+
+    def test_mount(self):
+        """Test normal mounting."""
+        with self.get_mount() as path:
+            self.assertTrue(path.is_mount())
+            self.assertTrue(path.exists())
+        self.assertFalse(path.is_mount())
+        # Unmounting should not remove the original folder
+        self.assertTrue(path.exists())
+
+    def test_mount_errors(self):
+        """Test invalid mount errors."""
+        cases = [
+            (dict(source="", target=str(uuid4()), fs="tmpfs"), OSError, "No such file"),
+            (dict(source=str(uuid4()), target="some/dir", fs="tmpfs"), OSError, "No such file"),
+            (
+                dict(source="", target=self.temp_dir, fs="tmpfs", invalid_opt="?"),
+                OSError,
+                "Invalid argument",
+            ),
+        ]
+        for case, err, msg in cases:
+            with self.subTest(case=case):
+                with self.assertRaises(err) as cm:
+                    mount(**case)
+                self.assertIn(msg, str(cm.exception))
+
+    def test_mount_duplicate(self):
+        """Test attempted mount after mounted."""
+        path = self.temp_dir / str(uuid4())
+        path.mkdir()
+        try:
+            mount(source="", target=path, fs="tmpfs")
+            with self.assertRaises(OSError) as cm:
+                mount(source="", target=path, fs="tmpfs")
+            self.assertIn("already a mount point", str(cm.exception))
+        finally:
+            unmount(target=path)
+
+    def test_unmount_flags(self):
+        """Test unmount flags."""
+        flags = [
+            UnmountFlags.MNT_FORCE,
+            UnmountFlags.MNT_DETACH,
+            UnmountFlags.UMOUNT_NOFOLLOW,
+        ]
+        for flag in flags:
+            with self.subTest(flag=flag), self.get_mount() as path:
+                self.assertTrue(path.is_mount())
+                unmount(path, flag)
+                self.assertFalse(path.is_mount())
+
+    def test_unmount_flags_expire(self):
+        """Test unmount MNT_EXPIRE behavior."""
+        with self.get_mount() as path:
+            with self.assertRaises(BlockingIOError):
+                unmount(path, UnmountFlags.MNT_EXPIRE)
+
+    def test_unmount_errors(self):
+        """Test invalid unmount errors."""
+        cases = [
+            (dict(target="not/exist"), OSError, "is not a mount point"),
+            (dict(target=Path("not/exist")), OSError, "is not a mount point"),
+        ]
+        for case, err, msg in cases:
+            with self.subTest(case=case):
+                with self.assertRaises(err) as cm:
+                    unmount(**case)
+                self.assertIn(msg, str(cm.exception))
+
+    def test_unmount_invalid_args(self):
+        """Test invalid unmount invalid flag."""
+        with self.get_mount() as path:
+            with self.assertRaises(OSError) as cm:
+                unmount(path, 251)
+            self.assertIn("Invalid argument", str(cm.exception))
+
+    def test_threading(self):
+        """Test concurrent mounting works in multi-thread environments."""
+        paths = [self.temp_dir / str(uuid4()) for _ in range(16)]
+
+        for path in paths:
+            path.mkdir()
+            self.assertFalse(path.is_mount())
+
+        try:
+            with ThreadPoolExecutor() as pool:
+                res = list(
+                    pool.map(
+                        mount,
+                        [""] * len(paths),
+                        paths,
+                        ["tmpfs"] * len(paths),
+                    )
+                )
+                self.assertEqual(len(res), len(paths))
+
+                for path in paths:
+                    with self.subTest(path=path):
+                        self.assertTrue(path.is_mount())
+
+                unmounts = list(pool.map(unmount, paths))
+                self.assertEqual(len(unmounts), len(paths))
+
+                for path in paths:
+                    with self.subTest(path=path):
+                        self.assertFalse(path.is_mount())
+        finally:
+            with suppress(OSError):
+                for path in paths:
+                    unmount(path)