[geary] Do not show "Labels" folders entry in sidemenu if there are none. Bug 754802

[Michael Gratton <mjog src gnome org>]

commit ff95fb819f72e7199824b7292ce5de54cc69ae7e
Author: Gautier Pelloux-Prayer <gautier+git damsy net>
Date:   Thu Mar 2 11:54:59 2017 +0100

    Do not show "Labels" folders entry in sidemenu if there are none. Bug 754802

 .../folder-list/folder-list-account-branch.vala    |   19 +++++++++++++++++--
 src/client/sidebar/sidebar-tree.vala               |    8 ++++----
 src/engine/api/geary-account-information.vala      |    4 ++--
 3 files changed, 23 insertions(+), 8 deletions(-)
---
diff --git a/src/client/folder-list/folder-list-account-branch.vala 
b/src/client/folder-list/folder-list-account-branch.vala
index 465e9a5..877fb85 100644
--- a/src/client/folder-list/folder-list-account-branch.vala
+++ b/src/client/folder-list/folder-list-account-branch.vala
@@ -20,14 +20,14 @@ public class FolderList.AccountBranch : Sidebar.Branch {
         
         account.information.notify["nickname"].connect(on_nicknamed_changed);
         
-        graft(get_root(), user_folder_group);
-        
         entry_removed.connect(on_entry_removed);
+        entry_moved.connect(check_user_folders);
     }
     
     ~AccountBranch() {
         account.information.notify["nickname"].disconnect(on_nicknamed_changed);
         entry_removed.disconnect(on_entry_removed);
+        entry_moved.disconnect(check_user_folders);
     }
     
     private void on_nicknamed_changed() {
@@ -87,6 +87,10 @@ public class FolderList.AccountBranch : Sidebar.Branch {
         } else if (folder.path.get_parent() == null) {
             // Top-level folders get put in our special user folders group.
             graft_point = user_folder_group;
+
+            if (!has_entry(user_folder_group)) {
+                graft(get_root(), user_folder_group);
+            }
         } else {
             Sidebar.Entry? entry = folder_entries.get(folder.path.get_parent());
             if (entry != null)
@@ -129,5 +133,16 @@ public class FolderList.AccountBranch : Sidebar.Branch {
         FolderEntry? folder_entry = entry as FolderEntry;
         if (folder_entry != null && folder_entries.has_key(folder_entry.folder.path))
             folder_entries.unset(folder_entry.folder.path);
+
+        check_user_folders(entry);
+    }
+
+    private void check_user_folders(Sidebar.Entry entry) {
+        if (entry != user_folder_group) {
+            // remove "Labels" entry if there are no more user entries
+            if (has_entry(user_folder_group) && (get_child_count(user_folder_group) == 0)) {
+                prune(user_folder_group);
+            }
+        }
     }
 }
diff --git a/src/client/sidebar/sidebar-tree.vala b/src/client/sidebar/sidebar-tree.vala
index 7136f2f..e5c5ac7 100644
--- a/src/client/sidebar/sidebar-tree.vala
+++ b/src/client/sidebar/sidebar-tree.vala
@@ -641,10 +641,10 @@ public class Sidebar.Tree : Gtk.TreeView {
     
     private void on_branch_entry_removed(Sidebar.Branch branch, Sidebar.Entry entry) {
         EntryWrapper? wrapper = get_wrapper(entry);
-        assert(wrapper != null);
-        assert(!(wrapper is RootWrapper));
-        
-        disassociate_wrapper_and_signal(wrapper, false);
+        if (wrapper != null) {
+            assert(!(wrapper is RootWrapper));
+            disassociate_wrapper_and_signal(wrapper, false);
+        }
     }
     
     private void on_branch_entry_moved(Sidebar.Branch branch, Sidebar.Entry entry) {
diff --git a/src/engine/api/geary-account-information.vala b/src/engine/api/geary-account-information.vala
index c2a34b3..0b0ce5e 100644
--- a/src/engine/api/geary-account-information.vala
+++ b/src/engine/api/geary-account-information.vala
@@ -466,8 +466,8 @@ public class Geary.AccountInformation : BaseObject {
     /**
      * Sets the path Geary will look for or create a special folder.  This is
      * only obeyed if the server doesn't tell Geary which folders are special.
-     * Only the DRAFTS, SENT, SPAM, and TRASH special folder types are valid to
-     * pass to this function.
+     * Only the DRAFTS, SENT, SPAM, TRASH and ARCHIVE special folder types are
+     * valid to pass to this function.
      */
     public void set_special_folder_path(Geary.SpecialFolderType special, Geary.FolderPath? path) {
         switch (special) {