[gnome-builder/wip/libide] libide: add internal helper to discover most recent file position

[Christian Hergert <chergert src gnome org>]

commit a5590643c2da6c4d6f2ee1b39a6b14a075eef4f6
Author: Christian Hergert <christian hergert me>
Date:   Thu Mar 12 19:13:58 2015 -0700

    libide: add internal helper to discover most recent file position
    
    This let's us piggyback on the navigation list to get the previous position
    within a file. Sort of nice so we don't need to track things in multiple
    places.

 libide/ide-back-forward-list.c |   53 +++++++++++++++++++++++++++++
 libide/ide-internal.h          |   72 +++++++++++++++++++++-------------------
 2 files changed, 91 insertions(+), 34 deletions(-)
---
diff --git a/libide/ide-back-forward-list.c b/libide/ide-back-forward-list.c
index 1103100..0f0f834 100644
--- a/libide/ide-back-forward-list.c
+++ b/libide/ide-back-forward-list.c
@@ -22,6 +22,8 @@
 
 #include "ide-back-forward-item.h"
 #include "ide-back-forward-list.h"
+#include "ide-file.h"
+#include "ide-source-location.h"
 
 struct _IdeBackForwardList
 {
@@ -429,3 +431,54 @@ ide_back_forward_list_init (IdeBackForwardList *self)
   self->backward = g_queue_new ();
   self->forward = g_queue_new ();
 }
+
+/**
+ * _ide_back_forward_list_find:
+ * @self: A #IdeBackForwardList.
+ * @file: The target #IdeFile
+ *
+ * This internal function will attempt to discover the most recent jump point for @file. It starts
+ * from the most recent item and works backwards until the target file is found or the list is
+ * exhausted.
+ *
+ * This is useful if you want to place the insert mark on the last used position within the buffer.
+ *
+ * Returns: (transfer none): An #IdeBackForwardItem or %NULL.
+ */
+IdeBackForwardItem *
+_ide_back_forward_list_find (IdeBackForwardList *self,
+                             IdeFile            *file)
+{
+  GList *iter;
+
+  g_return_val_if_fail (IDE_IS_BACK_FORWARD_LIST (self), NULL);
+  g_return_val_if_fail (IDE_IS_FILE (file), NULL);
+
+  for (iter = self->forward->tail; iter; iter = iter->prev)
+    {
+      IdeBackForwardItem *item = iter->data;
+      IdeSourceLocation *item_loc;
+      IdeFile *item_file;
+
+      item_loc = ide_back_forward_item_get_location (item);
+      item_file = ide_source_location_get_file (item_loc);
+
+      if (ide_file_equal (item_file, file))
+        return item;
+    }
+
+  for (iter = self->backward->head; iter; iter = iter->next)
+    {
+      IdeBackForwardItem *item = iter->data;
+      IdeSourceLocation *item_loc;
+      IdeFile *item_file;
+
+      item_loc = ide_back_forward_item_get_location (item);
+      item_file = ide_source_location_get_file (item_loc);
+
+      if (ide_file_equal (item_file, file))
+        return item;
+    }
+
+  return NULL;
+}
diff --git a/libide/ide-internal.h b/libide/ide-internal.h
index 409e4bb..32a4100 100644
--- a/libide/ide-internal.h
+++ b/libide/ide-internal.h
@@ -22,6 +22,8 @@
 #include <clang-c/Index.h>
 #include <gtksourceview/gtksource.h>
 
+#include "ide-back-forward-item.h"
+#include "ide-back-forward-list.h"
 #include "ide-clang-translation-unit.h"
 #include "ide-diagnostic.h"
 #include "ide-types.h"
@@ -30,40 +32,42 @@
 
 G_BEGIN_DECLS
 
-void               _ide_diagnostic_add_range          (IdeDiagnostic         *self,
-                                                       IdeSourceRange        *range);
-IdeDiagnostic     *_ide_diagnostic_new                (IdeDiagnosticSeverity  severity,
-                                                       const gchar           *text,
-                                                       IdeSourceLocation     *location);
-void               _ide_diagnostic_take_range         (IdeDiagnostic         *self,
-                                                       IdeSourceRange        *range);
-void               _ide_diagnostician_add_provider    (IdeDiagnostician      *self,
-                                                       IdeDiagnosticProvider *provider);
-void               _ide_diagnostician_remove_provider (IdeDiagnostician      *self,
-                                                       IdeDiagnosticProvider *provider);
-IdeDiagnostics    *_ide_diagnostics_new               (GPtrArray             *ar);
-GtkSourceFile     *_ide_file_get_source_file          (IdeFile               *file);
-void               _ide_project_set_name              (IdeProject            *project,
-                                                       const gchar           *name);
-void               _ide_search_context_add_provider   (IdeSearchContext      *context,
-                                                       IdeSearchProvider     *provider,
-                                                       gsize                  max_results);
-IdeSourceRange    *_ide_source_range_new              (IdeSourceLocation     *begin,
-                                                       IdeSourceLocation     *end);
-gboolean           _ide_source_view_mode_do_event     (IdeSourceViewMode     *mode,
-                                                       GdkEventKey           *event,
-                                                       gboolean              *remove);
-IdeSourceViewMode *_ide_source_view_mode_new          (GtkWidget             *view,
-                                                       const char            *mode,
-                                                       IdeSourceViewModeType  type);
-void               _ide_source_view_set_count         (IdeSourceView         *self,
-                                                       guint                  count);
-void               _ide_source_view_set_modifier      (IdeSourceView         *self,
-                                                       gunichar               modifier);
-IdeUnsavedFile    *_ide_unsaved_file_new              (GFile                 *file,
-                                                       GBytes                *content,
-                                                       const gchar           *temp_path,
-                                                       gint64                 sequence);
+IdeBackForwardItem *_ide_back_forward_list_find        (IdeBackForwardList    *self,
+                                                        IdeFile               *file);
+void                _ide_diagnostic_add_range          (IdeDiagnostic         *self,
+                                                        IdeSourceRange        *range);
+IdeDiagnostic      *_ide_diagnostic_new                (IdeDiagnosticSeverity  severity,
+                                                        const gchar           *text,
+                                                        IdeSourceLocation     *location);
+void                _ide_diagnostic_take_range         (IdeDiagnostic         *self,
+                                                        IdeSourceRange        *range);
+void                _ide_diagnostician_add_provider    (IdeDiagnostician      *self,
+                                                        IdeDiagnosticProvider *provider);
+void                _ide_diagnostician_remove_provider (IdeDiagnostician      *self,
+                                                        IdeDiagnosticProvider *provider);
+IdeDiagnostics     *_ide_diagnostics_new               (GPtrArray             *ar);
+GtkSourceFile      *_ide_file_get_source_file          (IdeFile               *file);
+void                _ide_project_set_name              (IdeProject            *project,
+                                                        const gchar           *name);
+void                _ide_search_context_add_provider   (IdeSearchContext      *context,
+                                                        IdeSearchProvider     *provider,
+                                                        gsize                  max_results);
+IdeSourceRange     *_ide_source_range_new              (IdeSourceLocation     *begin,
+                                                        IdeSourceLocation     *end);
+gboolean            _ide_source_view_mode_do_event     (IdeSourceViewMode     *mode,
+                                                        GdkEventKey           *event,
+                                                        gboolean              *remove);
+IdeSourceViewMode  *_ide_source_view_mode_new          (GtkWidget             *view,
+                                                        const char            *mode,
+                                                        IdeSourceViewModeType  type);
+void                _ide_source_view_set_count         (IdeSourceView         *self,
+                                                        guint                  count);
+void                _ide_source_view_set_modifier      (IdeSourceView         *self,
+                                                        gunichar               modifier);
+IdeUnsavedFile     *_ide_unsaved_file_new              (GFile                 *file,
+                                                        GBytes                *content,
+                                                        const gchar           *temp_path,
+                                                        gint64                 sequence);
 
 G_END_DECLS