[geary/mjog/composer-context-loading-fixes: 11/19] Geary.RFC822.MessageIDList: Replace append with concatenate

[Michael Gratton <mjog src gnome org>]

commit c41515a2c7dc32bcee68948c3fa2a9b99fb3724f
Author: Michael Gratton <mike vee net>
Date:   Wed Aug 12 10:10:20 2020 +1000

    Geary.RFC822.MessageIDList: Replace append with concatenate
    
    Add new method for appending a single id, rename to `concatenate` to
    disambiguate.

 src/engine/rfc822/rfc822-message-data.vala | 27 +++++++++++++++++++++++----
 src/engine/rfc822/rfc822-message.vala      |  2 +-
 2 files changed, 24 insertions(+), 5 deletions(-)
---
diff --git a/src/engine/rfc822/rfc822-message-data.vala b/src/engine/rfc822/rfc822-message-data.vala
index ee06727ae..09aa1d4ed 100644
--- a/src/engine/rfc822/rfc822-message-data.vala
+++ b/src/engine/rfc822/rfc822-message-data.vala
@@ -67,6 +67,7 @@ public class Geary.RFC822.MessageID :
 
 }
 
+
 /**
  * A immutable list of RFC822 Message-ID values.
  */
@@ -88,17 +89,26 @@ public class Geary.RFC822.MessageIDList :
     private Gee.List<MessageID> list = new Gee.ArrayList<MessageID>();
 
 
+    /**
+     * Constructs a new Message-Id list.
+     *
+     * If the optional collection of ids is not given, the list
+     * is created empty. Otherwise the collection's ids are
+     * added to the list by iterating over it in natural order.
+     */
     public MessageIDList(Gee.Collection<MessageID>? collection = null) {
         if (collection != null) {
             this.list.add_all(collection);
         }
     }
 
-    public MessageIDList.single(MessageID msg_id) {
+    /** Constructs a new Message-Id list containing a single id. */
+    public MessageIDList.single(MessageID msg_id){
         this();
         list.add(msg_id);
     }
 
+    /** Constructs a new Message-Id list by parsing a RFC822 string. */
     public MessageIDList.from_rfc822_string(string rfc822)
         throws Error {
         this();
@@ -201,10 +211,19 @@ public class Geary.RFC822.MessageIDList :
     }
 
     /**
-     * Returns a new list with the given messages ids appended to this list's.
+     * Returns a new list with the given list appended to this.
+     */
+    public MessageIDList concatenate_id(MessageID other) {
+        var new_ids = new MessageIDList(this.list);
+        new_ids.list.add(other);
+        return new_ids;
+    }
+
+    /**
+     * Returns a new list with the given list appended to this.
      */
-    public MessageIDList append(MessageIDList others) {
-        MessageIDList new_ids = new MessageIDList(this.list);
+    public MessageIDList concatenate_list(MessageIDList others) {
+        var new_ids = new MessageIDList(this.list);
         new_ids.list.add_all(others.list);
         return new_ids;
     }
diff --git a/src/engine/rfc822/rfc822-message.vala b/src/engine/rfc822/rfc822-message.vala
index e995f430b..4459180c2 100644
--- a/src/engine/rfc822/rfc822-message.vala
+++ b/src/engine/rfc822/rfc822-message.vala
@@ -960,7 +960,7 @@ public class Geary.RFC822.Message : BaseObject, EmailHeaderSet {
             try {
                 ids = new MessageIDList.from_rfc822_string(header_value);
                 if (existing != null) {
-                    ids = existing.append(ids);
+                    ids = existing.concatenate_list(ids);
                 }
             } catch (Error err) {
                 // Can't simply throw this since we need to be as lax as