[gitg/wip/commit: 23/28] Get head tree asynchronously

[Jesse van den Kieboom <jessevdk src gnome org>]

commit c66b61e969748d73a81ea9384c343b0b7042df2c
Author: Jesse van den Kieboom <jessevdk gmail com>
Date:   Wed Jul 3 16:41:22 2013 +0200

    Get head tree asynchronously

 libgitg/gitg-stage.vala |   38 +++++++++++++++++++++++++++++++-------
 1 files changed, 31 insertions(+), 7 deletions(-)
---
diff --git a/libgitg/gitg-stage.vala b/libgitg/gitg-stage.vala
index 11040d8..0fc0267 100644
--- a/libgitg/gitg-stage.vala
+++ b/libgitg/gitg-stage.vala
@@ -24,6 +24,7 @@ public class Stage : Object
 {
        private weak Repository d_repository;
        private Mutex d_index_mutex;
+       private Ggit.Tree? d_head_tree;
 
        internal Stage(Repository repository)
        {
@@ -37,12 +38,37 @@ public class Stage : Object
                });
        }
 
-       public StageStatusEnumerator file_status()
+       public async Ggit.Tree? get_head_tree() throws Error
        {
-               if (d_enumerator == null)
+               if (d_head_tree != null)
                {
+                       return d_head_tree;
                }
 
+               Error? e = null;
+
+               yield Async.thread(() => {
+                       try
+                       {
+                               var head = d_repository.get_head();
+                               var commit = (Ggit.Commit)head.lookup();
+
+                               d_head_tree = commit.get_tree();
+                       }
+                       catch (Error err)
+                       {
+                               e = err;
+                       }
+               });
+
+               if (e != null)
+               {
+                       throw e;
+               }
+
+               return d_head_tree;
+       }
+
        public StageStatusEnumerator file_status(Ggit.StatusOptions? options = null)
        {
                return new StageStatusEnumerator(d_repository, options);
@@ -80,12 +106,9 @@ public class Stage : Object
         */
        public async void revert(File file) throws Error
        {
-               yield thread_index((index) => {
-                       // lookup the tree of HEAD
-                       var head = d_repository.get_head();
-                       var commit = (Ggit.Commit)head.lookup();
-                       var tree = commit.get_tree();
+               var tree = yield get_head_tree();
 
+               yield thread_index((index) => {
                        // get path relative to the repository working directory
                        var wd = d_repository.get_workdir();
                        var path = wd.get_relative_path(file);
@@ -98,6 +121,7 @@ public class Stage : Object
                        var blob = d_repository.lookup<Ggit.Blob>(id);
 
                        var stream = file.replace(null, false, FileCreateFlags.NONE);
+
                        stream.write_all(blob.get_raw_content(), null);
                        stream.close();