[gtk+] Fix erroneous usage of height-for-width apis in gtk_widget_real_adjust_size_allocation().

[Tristan Van Berkom <tvb src gnome org>]

commit 7047502d846713fee8f271354c86afa5dd63ffdd
Author: Tristan Van Berkom <tristan van berkom gmail com>
Date:   Mon Sep 27 21:15:16 2010 +0900

    Fix erroneous usage of height-for-width apis in gtk_widget_real_adjust_size_allocation().
    
    When fitting a widget into its allocation, the second dimension
    is always dependent on the first, so gtk_widget_get_preferred_size()
    cannot be used directly (because we want the natural height for
    the allocated width, not the natural height for the natural width,
    which is generally a smaller height than the height-for-minimum-width
    or height-for-allocated-width).
    
    Added test to testadjustsize to ensure proper behaviour.

 gtk/gtkwidget.c        |   47 ++++++++++++++++++++++++++++++++++-------------
 tests/testadjustsize.c |   35 +++++++++++++++++++++++++++++++++++
 2 files changed, 69 insertions(+), 13 deletions(-)
---
diff --git a/gtk/gtkwidget.c b/gtk/gtkwidget.c
index 9472578..b4499e7 100644
--- a/gtk/gtkwidget.c
+++ b/gtk/gtkwidget.c
@@ -4685,23 +4685,44 @@ gtk_widget_real_adjust_size_allocation (GtkWidget         *widget,
                                         GtkAllocation     *allocation)
 {
   const GtkWidgetAuxInfo *aux_info;
-  GtkRequisition min, natural;
+  gint natural_width;
+  gint natural_height;
   int x, y, w, h;
 
   aux_info = _gtk_widget_get_aux_info_or_defaults (widget);
 
-  gtk_widget_get_preferred_size (widget, &min, &natural);
-
-  get_span_inside_border_horizontal (widget,
-                                     aux_info,
-                                     allocation->width,
-                                     natural.width,
-                                     &x, &w);
-  get_span_inside_border_vertical (widget,
-                                   aux_info,
-                                   allocation->height,
-                                   natural.height,
-                                   &y, &h);
+  if (gtk_widget_get_request_mode (widget) == GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH)
+    {
+      gtk_widget_get_preferred_width (widget, NULL, &natural_width);
+      get_span_inside_border_horizontal (widget,
+					 aux_info,
+					 allocation->width,
+					 natural_width,
+					 &x, &w);
+
+      gtk_widget_get_preferred_height_for_width (widget, w, NULL, &natural_height);
+      get_span_inside_border_vertical (widget,
+				       aux_info,
+				       allocation->height,
+				       natural_height,
+				       &y, &h);
+    }
+  else /* GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT */
+    {
+      gtk_widget_get_preferred_height (widget, NULL, &natural_height);
+      get_span_inside_border_vertical (widget,
+				       aux_info,
+				       allocation->height,
+				       natural_height,
+				       &y, &h);
+
+      gtk_widget_get_preferred_width_for_height (widget, h, NULL, &natural_width);
+      get_span_inside_border_horizontal (widget,
+					 aux_info,
+					 allocation->width,
+					 natural_width,
+					 &x, &w);
+    }
 
   allocation->x += x;
   allocation->y += y;
diff --git a/tests/testadjustsize.c b/tests/testadjustsize.c
index 5e9795c..889ea52 100644
--- a/tests/testadjustsize.c
+++ b/tests/testadjustsize.c
@@ -394,6 +394,40 @@ open_margin_window (void)
   gtk_widget_show_all (test_window);
 }
 
+static void
+open_valigned_label_window (void)
+{
+  GtkWidget *window, *box, *label, *frame;
+
+  window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
+
+  g_signal_connect (test_window, "delete-event",
+                    G_CALLBACK (gtk_main_quit), test_window);
+
+  box = gtk_vbox_new (FALSE, 0);
+  gtk_widget_show (box);
+  gtk_container_add (GTK_CONTAINER (window), box);
+
+
+  label = gtk_label_new ("Some wrapping text with width-chars = 15 and max-width-chars = 35");
+  gtk_label_set_line_wrap  (GTK_LABEL (label), TRUE);
+  gtk_label_set_width_chars  (GTK_LABEL (label), 15);
+  gtk_label_set_max_width_chars  (GTK_LABEL (label), 35);
+
+  gtk_widget_show (label);
+
+  frame  = gtk_frame_new (NULL);
+  gtk_widget_show (frame);
+  gtk_container_add (GTK_CONTAINER (frame), label);
+
+  gtk_widget_set_valign (frame, GTK_ALIGN_CENTER);
+  gtk_widget_set_halign (frame, GTK_ALIGN_FILL);
+
+  gtk_box_pack_start (GTK_BOX (box), frame, TRUE, TRUE, 0);
+
+  gtk_window_present (GTK_WINDOW (window));
+}
+
 int
 main (int argc, char *argv[])
 {
@@ -403,6 +437,7 @@ main (int argc, char *argv[])
   open_control_window ();
   open_alignment_window ();
   open_margin_window ();
+  open_valigned_label_window ();
 
   gtk_main ();