get_url returns different urls calling twice (bug #506)

bandit/core/docs_utils.py

@@ -37,10 +37,12 @@ def get_url(bid):
         if info['id'].startswith('B3'):  # B3XX
             # Some of the links are combined, so we have exception cases
             if info['id'] in ['B304', 'B305']:
+                info = info.copy()
                 info['id'] = 'b304-b305'
                 info['name'] = 'ciphers-and-modes'
             elif info['id'] in ['B313', 'B314', 'B315', 'B316', 'B317',
                                 'B318', 'B319', 'B320']:
+                info = info.copy()
                 info['id'] = 'b313-b320'
             ext = template.format(
                 kind='calls', id=info['id'], name=info['name'])

tests/unit/core/test_docs_util.py

@@ -0,0 +1,37 @@
+# Copyright 2019 Victor Torre
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+import testtools
+
+from bandit.core.docs_utils import BASE_URL
+from bandit.core.docs_utils import get_url
+
+
+class DocsUtilTests(testtools.TestCase):
+    '''This set of tests exercises bandit.core.docs_util functions.'''
+
+    def test_overwrite_bib_info(self):
+        expected_url = BASE_URL + ("blacklists/blacklist_calls.html"
+                                   "#b304-b305-ciphers-and-modes")
+        self.assertEqual(get_url('B304'), get_url('B305'))
+        self.assertEqual(expected_url, get_url('B304'))
+
+    def test_plugin_call_bib(self):
+        expected_url = BASE_URL + "plugins/b101_assert_used.html"
+        self.assertEqual(expected_url, get_url('B101'))
+
+    def test_import_call_bib(self):
+        expected_url = BASE_URL + ("blacklists/blacklist_imports.html"
+                                   "#b413-import-pycrypto")
+        self.assertEqual(expected_url, get_url('B413'))