Very basic autotesting

tests/high/test_mounted_fs.py

@@ -0,0 +1,39 @@
+from unittest import TestCase, mock
+import os
+
+from refuse.high import Operations
+
+from tests.tools import fuse_high_mountpoint
+
+
+class MountedFSTestCase(TestCase):
+    def test_init_gets_called(self):
+        with mock.patch.object(Operations, 'init') as mocked:
+            mocked.return_value = None
+            with fuse_high_mountpoint():
+                pass
+            mocked.assert_called_once_with('/')
+
+    def test_destroy_gets_called(self):
+        with mock.patch.object(Operations, 'destroy') as mocked:
+            mocked.return_value = None
+            with fuse_high_mountpoint():
+                pass
+            mocked.assert_called_once_with('/')
+
+    def test_readdir_root(self):
+        with fuse_high_mountpoint() as mountpoint:
+            self.assertEqual(
+                os.listdir(mountpoint),
+                [],
+            )
+
+    def test_readdir_root_nonempty(self):
+        with mock.patch.object(Operations, 'readdir') as mocked_readdir:
+            mocked_readdir.return_value = ['.', '..', 'omg_an_entry']
+            with fuse_high_mountpoint() as mountpoint:
+                self.assertEqual(
+                    os.listdir(mountpoint),
+                    ['omg_an_entry'],
+                )
+            mocked_readdir.assert_called_once_with('/', 0)

tests/low/test_mounted_fs.py

@@ -0,0 +1,22 @@
+from unittest import TestCase, mock
+
+from refuse.low import FUSELL
+
+from tests.tools import fuse_low_mountpoint
+
+
+class MountedFSTestCase(TestCase):
+    def test_init_gets_called(self):
+        with mock.patch.object(FUSELL, 'init') as mocked:
+            mocked.return_value = None
+            with fuse_low_mountpoint():
+                pass
+            # TODO - verify parameters (second parameter `conn` is hard)
+            mocked.assert_called_once()
+
+    def test_destroy_gets_called(self):
+        with mock.patch.object(FUSELL, 'destroy') as mocked:
+            mocked.return_value = None
+            with fuse_low_mountpoint():
+                pass
+            mocked.assert_called_once_with(None)

tests/tools.py

@@ -0,0 +1,103 @@
+from contextlib import contextmanager
+from threading import Thread
+import subprocess
+import tempfile
+import time
+
+from refuse.high import FUSE, Operations
+from refuse.low import FUSELL
+
+
+class MountTimeout(Exception):
+    pass
+
+
+class FUSEThread(Thread):
+    def __init__(
+        self,
+        mountpoint,
+        fuse_class,
+        **fuse_kwargs,
+    ):
+        super().__init__()
+        self.mountpoint = mountpoint
+        self.fuse_class = fuse_class
+        self.fuse_kwargs = fuse_kwargs
+
+    def run(self):
+        self.exc = None
+        try:
+            self.mount()
+        except Exception as e:
+            self.exc = e
+
+    def join(self):
+        super().join()
+        if self.exc:
+            raise self.exc
+
+    def mount(self):
+        self.fuse_class(
+            mountpoint=self.mountpoint,
+            **self.fuse_kwargs,
+        )
+
+    def unmount(self):
+        # fuse.fuse_exit() causes segafult
+        subprocess.run(
+            ['fusermount', '-u', self.mountpoint, '-q'],
+            check=self.is_alive(),  # this command has to succeed only if fuse thread is feeling good
+        )
+
+    def __enter__(self):
+        self.start()
+        return self
+
+    def __exit__(self, exc_type, exc_value, traceback):
+        self.unmount()
+        self.join()
+
+
+@contextmanager
+def fuse_mountpoint(
+    *args,
+    mount_timeout=5.0,  # seconds
+    **kwargs,
+):
+    with tempfile.TemporaryDirectory() as mountpoint:
+        with FUSEThread(mountpoint, *args, **kwargs) as fuse_thread:
+
+            # dirty dirty active waiting for now
+            # no idea how to do it the clean way
+            waiting_start = time.monotonic()
+            while fuse_thread.is_alive() and not is_mountpoint_ready(mountpoint):
+                if time.monotonic() - waiting_start > mount_timeout:
+                    raise MountTimeout()
+                time.sleep(0.01)
+
+            # do wrapped things
+            yield mountpoint
+
+
+def fuse_high_mountpoint():
+    operations = Operations()
+    setattr(operations, 'use_ns', True)
+    return fuse_mountpoint(FUSE, operations=operations, foreground=True)
+
+
+class FUSELLNS(FUSELL):
+    use_ns = True
+
+
+def fuse_low_mountpoint():
+    return fuse_mountpoint(FUSELLNS)
+
+
+def is_mountpoint_ready(mountpoint):
+    # AFAIK works only under linux. More platform-agnostic version may come later.
+    with open('/proc/mounts', 'rt') as mounts:
+        for mount in mounts:
+            typ, this_mountpoint, *_ = mount.split(' ')
+            if this_mountpoint == mountpoint:
+                return True
+    return False