add tests for man_no_space

tests/rules/test_man_no_space.py

@@ -0,0 +1,12 @@
+from thefuck.rules.man_no_space import match, get_new_command
+from tests.utils import Command
+
+
+def test_match():
+    assert match(Command('mandiff', stderr='mandiff: command not found'), None)
+    assert not match(Command(), None)
+
+
+def test_get_new_command():
+    assert get_new_command(
+        Command('mandiff'), None) == 'man diff'