[geary/mjog/571-imap-fetch-space-workaround-redux: 2/2] Fix RFC822.Header.get_header_names returning null names

[Michael Gratton <mjog src gnome org>]

commit ab77067d8aeb47834ccef330c736e57947f2661e
Author: Michael Gratton <mike vee net>
Date:   Thu Oct 10 08:55:42 2019 +1100

    Fix RFC822.Header.get_header_names returning null names
    
    The custom GMime VAPI assumed the call to get_iter() actually returned a
    new iter, but it doesn't. Fix that, update Header class style, and add
    tests.

 bindings/vapi/gmime-2.6.vapi               |  2 +-
 src/engine/rfc822/rfc822-message-data.vala | 26 +++++++++++---------------
 test/engine/rfc822-message-data-test.vala  | 22 ++++++++++++++++++++++
 3 files changed, 34 insertions(+), 16 deletions(-)
---
diff --git a/bindings/vapi/gmime-2.6.vapi b/bindings/vapi/gmime-2.6.vapi
index 2c4ad52a..7665a784 100644
--- a/bindings/vapi/gmime-2.6.vapi
+++ b/bindings/vapi/gmime-2.6.vapi
@@ -505,7 +505,7 @@ namespace GMime {
                [CCode (cname = "g_mime_header_list_get")]
                public unowned string @get (string name);
                [CCode (cname = "g_mime_header_list_get_iter")]
-               public bool get_iter (out unowned GMime.HeaderIter iter);
+               public bool get_iter (GMime.HeaderIter iter);
                [CCode (cname = "g_mime_header_list_get_stream")]
                public unowned GMime.Stream get_stream ();
                [CCode (cname = "g_mime_header_list_prepend")]
diff --git a/src/engine/rfc822/rfc822-message-data.vala b/src/engine/rfc822/rfc822-message-data.vala
index 0c8d9e17..2d399986 100644
--- a/src/engine/rfc822/rfc822-message-data.vala
+++ b/src/engine/rfc822/rfc822-message-data.vala
@@ -328,7 +328,7 @@ public class Geary.RFC822.Header : Geary.MessageData.BlockMessageData, Geary.RFC
     private string[]? names = null;
 
     public Header(Memory.Buffer buffer) {
-        base ("RFC822.Header", buffer);
+        base("RFC822.Header", buffer);
     }
 
     private unowned GMime.HeaderList get_headers() throws RFC822Error {
@@ -351,20 +351,16 @@ public class Geary.RFC822.Header : Geary.MessageData.BlockMessageData, Geary.RFC
     }
 
     public string[] get_header_names() throws RFC822Error {
-        if (names != null)
-            return names;
-
-        names = new string[0];
-
-        unowned GMime.HeaderIter iter;
-        if (!get_headers().get_iter(out iter))
-            return names;
-
-        do {
-            names += iter.get_name();
-        } while (iter.next());
-
-        return names;
+        if (this.names == null) {
+            this.names = new string[0];
+            GMime.HeaderIter iter = new GMime.HeaderIter();
+            if (get_headers().get_iter(iter) && iter.first()) {
+                do {
+                    names += iter.get_name();
+                } while (iter.next());
+            }
+        }
+        return this.names;
     }
 }
 
diff --git a/test/engine/rfc822-message-data-test.vala b/test/engine/rfc822-message-data-test.vala
index 2b849edb..504efaa0 100644
--- a/test/engine/rfc822-message-data-test.vala
+++ b/test/engine/rfc822-message-data-test.vala
@@ -10,7 +10,10 @@ class Geary.RFC822.MessageDataTest : TestCase {
     public MessageDataTest() {
         base("Geary.RFC822.MessageDataTest");
         add_test("date_from_rfc822", date_from_rfc822);
+        add_test("date_from_rfc822", date_from_rfc822);
         add_test("date_to_rfc822", date_to_rfc822);
+        add_test("header_from_rfc822", header_from_rfc822);
+        add_test("header_names_from_rfc822", header_names_from_rfc822);
         add_test("PreviewText.with_header", preview_text_with_header);
     }
 
@@ -42,6 +45,20 @@ class Geary.RFC822.MessageDataTest : TestCase {
         assert_string(HTML_BODY2_EXPECTED, html_preview2.buffer.to_string());
     }
 
+    public void header_from_rfc822() throws GLib.Error {
+        Header test_article = new Header(new Memory.StringBuffer(HEADER_FIXTURE));
+        assert_string("Test <test example com>", test_article.get_header("From"));
+        assert_string("test", test_article.get_header("Subject"));
+        assert_null_string(test_article.get_header("Blah"));
+    }
+
+    public void header_names_from_rfc822() throws GLib.Error {
+        Header test_article = new Header(new Memory.StringBuffer(HEADER_FIXTURE));
+        assert_int(2, test_article.get_header_names().length);
+        assert_string("From", test_article.get_header_names()[0]);
+        assert_string("Subject", test_article.get_header_names()[1]);
+    }
+
     public void date_from_rfc822() throws GLib.Error {
         const string FULL_HOUR_TZ = "Thu, 28 Feb 2019 00:00:00 -0100";
         Date full_hour_tz = new Date(FULL_HOUR_TZ);
@@ -92,6 +109,11 @@ class Geary.RFC822.MessageDataTest : TestCase {
     }
 
 
+    private const string HEADER_FIXTURE = """From: Test <test example com>
+Subject: test
+
+""";
+
     public static string PLAIN_BODY1_HEADERS = "Content-Type: text/plain; 
charset=\"us-ascii\"\r\nContent-Transfer-Encoding: 7bit\r\n";
     public static string PLAIN_BODY1_ENCODED = "-----BEGIN PGP SIGNED MESSAGE-----\r\nHash: 
SHA512\r\n\r\n=============================================================================\r\nFreeBSD-EN-16:11.vmbus
                                          Errata Notice\r\n                                                   
       The FreeBSD Project\r\n\r\nTopic:          Avoid using spin locks for channel message 
locks\r\n\r\nCategory:       core\r\nModule:         vmbus\r\nAnnounced:      2016-08-12\r\nCredits:        
Microsoft OSTC\r\nAffects:        FreeBSD 10.3\r\nCorrected:      2016-06-15 09:52:01 UTC (stable/10, 
10.3-STABLE)\r\n                2016-08-12 04:01:16 UTC (releng/10.3, 10.3-RELEASE-p7)\r\n\r\nFor general 
information regarding FreeBSD Errata Notices and Security\r\nAdvisories, including descriptions of the fields 
above, security\r\nbranches, and the following sections, please 
visit\r\n<URL:https://security.FreeBSD.org/>.\r\n";
     public static string PLAIN_BODY1_EXPECTED = "FreeBSD-EN-16:11.vmbus Errata Notice The FreeBSD Project 
Topic: Avoid using spin locks for channel message locks Category: core Module: vmbus Announced: 2016-08-12 
Credits: Microsoft OSTC Affects: FreeBSD 10.3 Corrected: 2016-06-15 09:52:01 UTC (stable/10, 10.3-STABLE) 
2016-08-12 04:01:16 UTC (releng/10.3, 10.3-RELEASE-p7) For general information regarding FreeBSD Errata 
Notices and Security Advisories, including descriptions of the fields above, security branches, and the 
following sections, please visit <URL:https://security.FreeBSD.org/>.";