EC2: Fix unhandled error for nonexistent security groups (#7639)

Author: viren-nadkarni

moto/ec2/models/security_groups.py

@@ -812,6 +812,9 @@ def revoke_security_group_ingress(
             group_name_or_id, vpc_id
         )  # type: ignore[assignment]
 
+        if group is None:
+            raise InvalidSecurityGroupNotFoundError(group_name_or_id)
+
         if security_rule_ids:
             group.ingress_rules = [
                 rule for rule in group.ingress_rules if rule.id not in security_rule_ids
@@ -983,6 +986,9 @@ def revoke_security_group_egress(
             group_name_or_id, vpc_id
         )  # type: ignore[assignment]
 
+        if group is None:
+            raise InvalidSecurityGroupNotFoundError(group_name_or_id)
+
         if security_rule_ids:
             group.egress_rules = [
                 rule for rule in group.egress_rules if rule.id not in security_rule_ids

tests/test_ec2/test_security_groups.py

@@ -304,6 +304,13 @@ def test_authorize_ip_range_and_revoke():
         {"CidrIp": "123.123.123.123/32"}
     ]
 
+    # Bad group must produce error
+    with pytest.raises(ClientError) as ex:
+        client.revoke_security_group_egress(GroupId="badcompany")
+    assert ex.value.response["ResponseMetadata"]["HTTPStatusCode"] == 400
+    assert "RequestId" in ex.value.response["ResponseMetadata"]
+    assert ex.value.response["Error"]["Code"] == "InvalidGroup.NotFound"
+
     # Wrong Cidr should throw error
     with pytest.raises(ClientError) as ex:
         wrong_permissions = copy.deepcopy(egress_permissions)
@@ -380,6 +387,13 @@ def test_authorize_other_group_and_revoke():
     assert "RequestId" in ex.value.response["ResponseMetadata"]
     assert ex.value.response["Error"]["Code"] == "InvalidGroup.NotFound"
 
+    # Bad group must produce error
+    with pytest.raises(ClientError) as ex:
+        client.revoke_security_group_ingress(GroupId="badcompany")
+    assert ex.value.response["ResponseMetadata"]["HTTPStatusCode"] == 400
+    assert "RequestId" in ex.value.response["ResponseMetadata"]
+    assert ex.value.response["Error"]["Code"] == "InvalidGroup.NotFound"
+
     # Actually revoke
     security_group.revoke_ingress(IpPermissions=permissions)