GnuPG module: make key-listing more thorough

- Flush key-collecting structures each time a new public key entry is found.
  This will avoid adding sub-keys and overwriting main keys with them.

- Use parseaddr from email.utils to parse emails (and drop realname part).

- Record logs produced during unit tests.

- Fix a small bug in test code.

Also: add basic information about available test identities to testing
documentation.

GnuPG/__init__.py

@@ -34,6 +34,7 @@ from email.utils import parseaddr
 
 LINE_FINGERPRINT = 'fpr'
 LINE_USER_ID = 'uid'
+LINE_PUBLIC_KEY = 'pub'
 
 POS_FINGERPRINT = 9
 POS_UID = 9
@@ -73,16 +74,28 @@ def public_keys(keyhome, *, key_id=None):
     p.wait()
 
     keys = dict()
+    collected = set()
+
     fingerprint = None
     email = None
+
     for line in p.stdout.readlines():
         line = line.decode(sys.getdefaultencoding())
-        if line[0:3] == LINE_FINGERPRINT:
+
+        if line[0:3] == LINE_PUBLIC_KEY:
+            # New identity has started, reset state.
+            fingerprint = None
+            email = None
+
+        if line[0:3] == LINE_FINGERPRINT and not fingerprint:
             fingerprint = _extract_fingerprint(line)
+
         if line[0:3] == LINE_USER_ID:
             email = _parse_uid_line(line)
-        if not (fingerprint is None or email is None):
+
+        if fingerprint and email and not email in collected:
             keys[fingerprint] = email
+            collected.add(email)
             fingerprint = None
             email = None
 
@@ -104,7 +117,8 @@ def _parse_uid_line(line: str):
     if len(userid_line) <= POS_UID:
         return None
     else:
-        return userid_line[POS_UID]
+        (_, email) = parseaddr(userid_line[POS_UID])
+        return email
 
 
 def _to_bytes(s) -> bytes:

doc/testing.md

@@ -49,3 +49,11 @@ verifying that the correct key has been used. That's because we don't know
 
 When things go wrong, be sure to study `test/logs/e2e.log` and
 `test/logs/gpg-mailgate.log` files -- they contain some useful information.
+
+## Test identities
+
+There are several identities in test/keyhome and in the test database:
+
+* alice@disposlab: 1CD245308F0963D038E88357973CF4D9387C44D7
+* bob@disposlab: 19CF4B47ECC9C47AFA84D4BD96F39FDA0E31BB67
+* evan@disposlab: 530B1BB2D0CC7971648198BBA4774E507D3AF5BC

test/modules/test_gnupg.py

@@ -1,8 +1,14 @@
 import GnuPG
+import logging
 
 import unittest
 
 class GnuPGUtilitiesTest(unittest.TestCase):
+    def setUp(self):
+        # Record GnuPG logs:
+        logging.basicConfig(filename='test/logs/unittest.log', level=logging.DEBUG,
+                            format='%(asctime)s %(pathname)s:%(lineno)d %(levelname)s [%(funcName)s] %(message)s')
+
     def test_build_default_command(self):
         cmd = GnuPG._build_command("test/keyhome")
         self.assertEqual(cmd, ["gpg", "--homedir", "test/keyhome"])
@@ -38,7 +44,7 @@ class GnuPGUtilitiesTest(unittest.TestCase):
 
     def test_add_delete_key(self):
         self.assertDictEqual(GnuPG.public_keys('test/keyhome.other'), { })
-        GnuPG.add_key('test/keyhome', self._load('test/keys/bob@disposlab.pub'))
+        GnuPG.add_key('test/keyhome.other', self._load('test/keys/bob@disposlab.pub'))
         self.assertDictEqual(GnuPG.public_keys('test/keyhome.other'), {
             '19CF4B47ECC9C47AFA84D4BD96F39FDA0E31BB67': 'bob@disposlab',
         })