Merge pull request #1843 from Scille/fix-fuse-open-flags

Change fuse_operations open method flag mask + add test on open

newsfragments/1836.bugfix.rst

@@ -0,0 +1 @@
+Fixed a bug where some text editor could still edit files in a workspace as reader

parsec/core/mountpoint/fuse_operations.py

@@ -202,7 +202,7 @@ def create(self, path: FsPath, mode: int):
 
     def open(self, path: FsPath, flags: int = 0):
         # Filter file status and file creation flags
-        write_mode = flags in (os.O_WRONLY, os.O_RDWR)
+        write_mode = (flags % 4) in (os.O_WRONLY, os.O_RDWR)
         _, fd = self.fs_access.file_open(path, write_mode=write_mode)
         return fd
 

tests/core/mountpoint/test_base.py

@@ -396,6 +396,14 @@ async def assert_cannot_write(mountpoint_manager, new_role):
         with pytest.raises(expected_error) as ctx:
             await bar_path.unlink()
 
+        def sync_open():
+            for flag in (os.O_WRONLY, os.O_RDWR, os.O_RDWR | os.O_APPEND, os.O_WRONLY | os.O_EXCL):
+                with pytest.raises(expected_error) as ctx:
+                    os.open(foo_path, flag)
+                assert ctx.value.errno == expected_errno
+
+        await trio.to_thread.run_sync(sync_open)
+
     async with mountpoint_manager_factory(
         alice_user_fs, event_bus, base_mountpoint
     ) as mountpoint_manager: