Test & impl for truly functional HostKeys.__delitem__

2 files changed, 20 insertions, 1 deletions

diff --git a/paramiko/hostkeys.py b/paramiko/hostkeys.py
index 4be3fd42..b72abe40 100644
--- a/paramiko/hostkeys.py
+++ b/paramiko/hostkeys.py
@@ -246,7 +246,14 @@ class HostKeys (MutableMapping):
         return ret
 
     def __delitem__(self, key):
-        pass  # Needed for instantiating HostKeys.
+        index = None
+        for i, entry in enumerate(self._entries):
+            if self._hostname_matches(key, entry):
+                index = i
+                break
+        if i is None:
+            raise KeyError(key)
+        self._entries.pop(i)
 
     def __setitem__(self, hostname, entry):
         # don't use this please.
diff --git a/tests/test_hostkeys.py b/tests/test_hostkeys.py
index 2bdcad9c..2c7ceeb9 100644
--- a/tests/test_hostkeys.py
+++ b/tests/test_hostkeys.py
@@ -115,3 +115,15 @@ class HostKeysTest (unittest.TestCase):
         self.assertEqual(b'7EC91BB336CB6D810B124B1353C32396', fp)
         fp = hexlify(hostdict['secure.example.com']['ssh-dss'].get_fingerprint()).upper()
         self.assertEqual(b'4478F0B9A23CC5182009FF755BC1D26C', fp)
+
+    def test_delitem(self):
+        hostdict = paramiko.HostKeys('hostfile.temp')
+        target = 'happy.example.com'
+        entry = hostdict[target] # will KeyError if not present
+        del hostdict[target]
+        try:
+            entry = hostdict[target]
+        except KeyError:
+            pass # Good
+        else:
+            assert False, "Entry was not deleted from HostKeys on delitem!"