Tests for mountfile

fs/tests/test_mountfs.py

@@ -3,9 +3,9 @@ from fs.memoryfs import MemoryFS
 import unittest
 
 class TestMultiFS(unittest.TestCase):
-    
+
     def test_auto_close(self):
-        """Test MultiFS auto close is working"""        
+        """Test MultiFS auto close is working"""
         multi_fs = MountFS()
         m1 = MemoryFS()
         m2 = MemoryFS()
@@ -16,7 +16,7 @@ class TestMultiFS(unittest.TestCase):
         multi_fs.close()
         self.assert_(m1.closed)
         self.assert_(m2.closed)
-        
+
     def test_no_auto_close(self):
         """Test MultiFS auto close can be disabled"""
         multi_fs = MountFS(auto_close=False)
@@ -29,4 +29,46 @@ class TestMultiFS(unittest.TestCase):
         multi_fs.close()
         self.assert_(not m1.closed)
         self.assert_(not m2.closed)
-        
+
+    def test_mountfile(self):
+        """Test mounting a file"""
+        quote = """If you wish to make an apple pie from scratch, you must first invent the universe."""
+        mem_fs = MemoryFS()
+        mem_fs.makedir('foo')
+        mem_fs.setcontents('foo/bar.txt', quote)
+        foo_dir = mem_fs.opendir('foo')
+
+        mount_fs = MountFS()
+        mount_fs.mountfile('bar.txt', foo_dir.open, foo_dir.getinfo)
+
+        self.assert_(mount_fs.isdir('/'))
+        self.assert_(mount_fs.isdir('./'))
+        self.assert_(mount_fs.isdir(''))
+
+        # Check we can see the mounted file in the dir list
+        self.assertEqual(mount_fs.listdir(), ["bar.txt"])
+        self.assert_(not mount_fs.exists('nobodyhere.txt'))
+        self.assert_(mount_fs.exists('bar.txt'))
+        self.assert_(mount_fs.isfile('bar.txt'))
+        self.assert_(not mount_fs.isdir('bar.txt'))
+
+        # Check open and getinfo callables
+        self.assertEqual(mount_fs.getcontents('bar.txt'), quote)
+        self.assertEqual(mount_fs.getsize('bar.txt'), len(quote))
+
+        # Check changes are written back
+        mem_fs.setcontents('foo/bar.txt', 'baz')
+        self.assertEqual(mount_fs.getcontents('bar.txt'), 'baz')
+        self.assertEqual(mount_fs.getsize('bar.txt'), len('baz'))
+
+        # Check changes are written to the original fs
+        self.assertEqual(mem_fs.getcontents('foo/bar.txt'), 'baz')
+        self.assertEqual(mem_fs.getsize('foo/bar.txt'), len('baz'))
+
+        # Check unmount
+        self.assert_(mount_fs.unmount("bar.txt"))
+        self.assertEqual(mount_fs.listdir(), [])
+        self.assert_(not mount_fs.exists('bar.txt'))
+
+        # Check unount a second time is a null op, and returns False
+        self.assertFalse(mount_fs.unmount("bar.txt"))