[gnome-builder/wip/ggit] change-monitor: preload GgitBlob when setting target GFile

[Christian Hergert <chergert src gnome org>]

commit 3ecd927a94dcbebd9294208544220762586d2d0c
Author: Christian Hergert <christian hergert me>
Date:   Mon Sep 29 00:11:36 2014 -0700

    change-monitor: preload GgitBlob when setting target GFile
    
    This saves us a lot of walking the Git tree unnecessarly. It does mean,
    however, that if the file is added to git after the document is opened,
    it will need to be reoped to see the git-based changes.

 src/editor/gb-source-change-monitor.c |  195 +++++++++++++++++++--------------
 1 files changed, 115 insertions(+), 80 deletions(-)
---
diff --git a/src/editor/gb-source-change-monitor.c b/src/editor/gb-source-change-monitor.c
index 3adb941..874edd5 100644
--- a/src/editor/gb-source-change-monitor.c
+++ b/src/editor/gb-source-change-monitor.c
@@ -34,6 +34,8 @@ struct _GbSourceChangeMonitorPrivate
   GtkTextBuffer  *buffer;
   GFile          *file;
   GgitRepository *repo;
+  GgitBlob       *blob;
+  gchar          *relative_path;
   GHashTable     *state;
   guint           changed_handler;
   guint           parse_timeout;
@@ -66,17 +68,12 @@ gb_source_change_monitor_get_line (GbSourceChangeMonitor *monitor,
 {
   g_return_val_if_fail (GB_IS_SOURCE_CHANGE_MONITOR (monitor), 0);
 
-  /*
-   * We store line numbers as 1 based to simply the diff code.
-   */
-  lineno++;
-
   if (monitor->priv->state)
     {
       gpointer value;
 
       value = g_hash_table_lookup (monitor->priv->state,
-                                   GINT_TO_POINTER (lineno));
+                                   GINT_TO_POINTER (lineno + 1));
       return (GPOINTER_TO_INT (value) & GB_SOURCE_CHANGE_MASK);
     }
 
@@ -155,16 +152,7 @@ on_parse_timeout (GbSourceChangeMonitor *monitor)
   GbSourceChangeMonitorPrivate *priv;
   GtkTextIter begin;
   GtkTextIter end;
-  GgitOId *entry_oid = NULL;
-  GgitOId *oid = NULL;
-  GgitObject *blob = NULL;
-  GgitObject *commit = NULL;
-  GgitRef *head = NULL;
-  GgitTree *tree = NULL;
-  GgitTreeEntry *entry = NULL;
-  GFile *workdir = NULL;
   GError *error = NULL;
-  gchar *relpath = NULL;
   gchar *text = NULL;
 
   /*
@@ -173,12 +161,13 @@ on_parse_timeout (GbSourceChangeMonitor *monitor)
    *       new state to the main thread via an async worker func/cb.
    */
 
-  ENTRY;
-
   g_assert (GB_IS_SOURCE_CHANGE_MONITOR (monitor));
 
   priv = monitor->priv;
 
+  if (!priv->blob || !priv->relative_path || !priv->buffer || !priv->file)
+    return G_SOURCE_REMOVE;
+
   /*
    * First, disable this so any side-effects cause a new parse to occur.
    */
@@ -190,13 +179,98 @@ on_parse_timeout (GbSourceChangeMonitor *monitor)
   g_hash_table_remove_all (priv->state);
 
   /*
+   * Load the contents of the buffer from the GtkTextBuffer.
+   */
+  gtk_text_buffer_get_bounds (priv->buffer, &begin, &end);
+  text = gtk_text_buffer_get_text (priv->buffer, &begin, &end, TRUE);
+
+  /*
+   * Ask ggit to diff the buffer for us. We will get a callback for all of
+   * the changes that we can then turn into Add/Change line statuses.
+   */
+  ggit_diff_blob_to_buffer (priv->blob, priv->relative_path,
+                            (const guint8 *)text, -1, priv->relative_path,
+                            NULL, NULL, NULL, diff_line_cb,
+                            priv->state, &error);
+
+  if (error)
+    {
+      g_message ("Failed to generate diff: %s", error->message);
+      g_clear_error (&error);
+      GOTO (cleanup);
+    }
+
+  /*
+   * Notify any listeners (such as the gutter renderer) of potential changes.
+   */
+  g_signal_emit (monitor, gSignals [CHANGED], 0);
+
+cleanup:
+  g_free (text);
+
+  return G_SOURCE_REMOVE;
+}
+
+static void
+gb_source_change_monitor_queue_parse (GbSourceChangeMonitor *monitor)
+{
+  GbSourceChangeMonitorPrivate *priv;
+
+  g_return_if_fail (GB_IS_SOURCE_CHANGE_MONITOR (monitor));
+
+  priv = monitor->priv;
+
+  if (!priv->repo || !priv->blob || !priv->file)
+    return;
+
+  if (priv->parse_timeout)
+    {
+      g_source_remove (priv->parse_timeout);
+      priv->parse_timeout = 0;
+    }
+
+  priv->parse_timeout = g_timeout_add (PARSE_TIMEOUT_MSEC,
+                                       (GSourceFunc)on_parse_timeout,
+                                       monitor);
+}
+
+static void
+on_change_cb (GbSourceChangeMonitor *monitor,
+              GtkTextBuffer         *buffer)
+{
+  g_return_if_fail (GB_IS_SOURCE_CHANGE_MONITOR (monitor));
+  g_return_if_fail (GTK_IS_TEXT_BUFFER (buffer));
+
+  gb_source_change_monitor_queue_parse (monitor);
+}
+
+static void
+gb_source_change_monitor_load_blob (GbSourceChangeMonitor *monitor)
+{
+  GbSourceChangeMonitorPrivate *priv;
+  GgitOId *entry_oid = NULL;
+  GgitOId *oid = NULL;
+  GgitObject *blob = NULL;
+  GgitObject *commit = NULL;
+  GgitRef *head = NULL;
+  GgitTree *tree = NULL;
+  GgitTreeEntry *entry = NULL;
+  GFile *workdir = NULL;
+  GError *error = NULL;
+  gchar *relpath = NULL;
+
+  g_return_if_fail (GB_IS_SOURCE_CHANGE_MONITOR (monitor));
+
+  priv = monitor->priv;
+
+  /*
    * Double check we have everything we need.
    */
-  if (!priv->repo)
-    RETURN (G_SOURCE_REMOVE);
+  if (!priv->repo || !priv->file)
+    return;
 
   /*
-   * Work our way through ggit to get to the original blog we care about.
+   * Work our way through ggit to get to the original blob we care about.
    */
   head = ggit_repository_get_head (priv->repo, &error);
   if (!head)
@@ -234,17 +308,8 @@ on_parse_timeout (GbSourceChangeMonitor *monitor)
   if (!blob)
     GOTO (cleanup);
 
-  gtk_text_buffer_get_bounds (priv->buffer, &begin, &end);
-  text = gtk_text_buffer_get_text (priv->buffer, &begin, &end, TRUE);
-
-  ggit_diff_blob_to_buffer (GGIT_BLOB (blob), relpath, (const guint8 *)text,
-                            -1, relpath, NULL, NULL, NULL, diff_line_cb,
-                            priv->state, &error);
-
-  if (error)
-    GOTO (cleanup);
-
-  g_signal_emit (monitor, gSignals [CHANGED], 0);
+  priv->blob = g_object_ref (blob);
+  priv->relative_path = g_strdup (relpath);
 
 cleanup:
   if (error)
@@ -253,7 +318,6 @@ cleanup:
       g_clear_error (&error);
     }
 
-  g_clear_pointer (&text, g_free);
   g_clear_object (&blob);
   g_clear_pointer (&entry_oid, ggit_oid_free);
   g_clear_pointer (&entry, ggit_tree_entry_unref);
@@ -263,42 +327,10 @@ cleanup:
   g_clear_object (&commit);
   g_clear_pointer (&oid, ggit_oid_free);
   g_clear_object (&head);
-
-  RETURN (G_SOURCE_REMOVE);
-}
-
-static void
-gb_source_change_monitor_queue_parse (GbSourceChangeMonitor *monitor)
-{
-  GbSourceChangeMonitorPrivate *priv;
-
-  g_return_if_fail (GB_IS_SOURCE_CHANGE_MONITOR (monitor));
-
-  priv = monitor->priv;
-
-  if (priv->parse_timeout)
-    {
-      g_source_remove (priv->parse_timeout);
-      priv->parse_timeout = 0;
-    }
-
-  priv->parse_timeout = g_timeout_add (PARSE_TIMEOUT_MSEC,
-                                       (GSourceFunc)on_parse_timeout,
-                                       monitor);
 }
 
 static void
-on_change_cb (GbSourceChangeMonitor *monitor,
-              GtkTextBuffer         *buffer)
-{
-  g_return_if_fail (GB_IS_SOURCE_CHANGE_MONITOR (monitor));
-  g_return_if_fail (GTK_IS_TEXT_BUFFER (buffer));
-
-  gb_source_change_monitor_queue_parse (monitor);
-}
-
-static void
-discover_repository (GbSourceChangeMonitor *monitor)
+gb_source_change_monitor_discover_repository (GbSourceChangeMonitor *monitor)
 {
   GbSourceChangeMonitorPrivate *priv;
 
@@ -326,31 +358,20 @@ discover_repository (GbSourceChangeMonitor *monitor)
 
       repo_file = ggit_repository_discover (priv->file, &error);
 
-      TRACE;
-
       if (!repo_file)
         {
-          g_message ("%s", error->message);
+          g_message ("Failed to locate a gir repository: %s", error->message);
           g_clear_error (&error);
           EXIT;
         }
 
       priv->repo = ggit_repository_open (repo_file, &error);
-      TRACE;
 
       if (!priv->repo)
         {
-          g_message ("%s", error->message);
+          g_message ("Failed to open git repository: %s", error->message);
           g_clear_error (&error);
         }
-      else
-        {
-          gchar *uri;
-
-          uri = g_file_get_uri (repo_file);
-          g_message ("Discovered Git repository at \"%s\"", uri);
-          g_free (uri);
-        }
 
       g_clear_object (&repo_file);
     }
@@ -397,6 +418,8 @@ gb_source_change_monitor_set_buffer (GbSourceChangeMonitor *monitor,
                                  G_CONNECT_SWAPPED);
     }
 
+  gb_source_change_monitor_queue_parse (monitor);
+
   EXIT;
 }
 
@@ -425,10 +448,20 @@ gb_source_change_monitor_set_file (GbSourceChangeMonitor *monitor,
     EXIT;
 
   g_clear_object (&priv->file);
-  monitor->priv->file = file ? g_object_ref (file) : NULL;
-  discover_repository (monitor);
+  g_clear_object (&priv->blob);
+  g_clear_object (&priv->repo);
+
+  if (file)
+    {
+      priv->file = g_object_ref (file);
+      gb_source_change_monitor_discover_repository (monitor);
+      gb_source_change_monitor_load_blob (monitor);
+    }
+
   g_object_notify_by_pspec (G_OBJECT (monitor), gParamSpecs [PROP_FILE]);
 
+  gb_source_change_monitor_queue_parse (monitor);
+
   EXIT;
 }
 
@@ -443,6 +476,7 @@ gb_source_change_monitor_dispose (GObject *object)
   gb_source_change_monitor_set_file (monitor, NULL);
 
   g_clear_object (&monitor->priv->repo);
+  g_clear_object (&monitor->priv->blob);
 
   if (monitor->priv->parse_timeout)
     {
@@ -461,6 +495,7 @@ gb_source_change_monitor_finalize (GObject *object)
   GbSourceChangeMonitorPrivate *priv = GB_SOURCE_CHANGE_MONITOR (object)->priv;
 
   g_clear_pointer (&priv->state, g_hash_table_unref);
+  g_clear_pointer (&priv->relative_path, g_free);
 
   G_OBJECT_CLASS (gb_source_change_monitor_parent_class)->finalize (object);
 }