[egg-list-box] Make ChildInfo a class so we get rid of the by-value semantics

[Alexander Larsson <alexl src gnome org>]

commit 8d7860761c382ffd2c123ee5d948acca051f3484
Author: Alexander Larsson <alexl redhat com>
Date:   Wed May 16 12:14:28 2012 +0200

    Make ChildInfo a class so we get rid of the by-value semantics
    
    We were comparing equality by value, etc, and we had to use "?" everywhere to
    work around value copying. Better just use a class.

 egg-list-box.vala |  103 +++++++++++++++++++++++++++-------------------------
 1 files changed, 53 insertions(+), 50 deletions(-)
---
diff --git a/egg-list-box.vala b/egg-list-box.vala
index 8bd82e3..9b97374 100644
--- a/egg-list-box.vala
+++ b/egg-list-box.vala
@@ -22,24 +22,28 @@ public class Egg.ListBox : Container {
   public delegate bool FilterFunc (Widget child);
   public delegate void UpdateSeparatorFunc (ref Widget? separator, Widget child, Widget? before);
 
-  private struct ChildInfo {
-    Widget widget;
-    Widget? separator;
-    SequenceIter<ChildInfo?> iter;
-    int y;
-    int height;
+  private class ChildInfo {
+    public Widget widget;
+    public Widget? separator;
+    public SequenceIter<ChildInfo> iter;
+    public int y;
+    public int height;
+
+    public ChildInfo (Widget widget) {
+      this.widget = widget;
+    }
   }
 
-  private Sequence<ChildInfo?> children;
-  private HashTable<unowned Widget, unowned ChildInfo?> child_hash;
+  private Sequence<ChildInfo> children;
+  private HashTable<unowned Widget, unowned ChildInfo> child_hash;
   private CompareDataFunc<Widget>? sort_func;
   private FilterFunc? filter_func;
   private UpdateSeparatorFunc? update_separator_func;
-  private unowned ChildInfo? selected_child;
-  private unowned ChildInfo? prelight_child;
-  private unowned ChildInfo? cursor_child;
+  private unowned ChildInfo selected_child;
+  private unowned ChildInfo prelight_child;
+  private unowned ChildInfo cursor_child;
   bool active_child_active;
-  private unowned ChildInfo? active_child;
+  private unowned ChildInfo active_child;
   private SelectionMode selection_mode;
 
 
@@ -50,11 +54,11 @@ public class Egg.ListBox : Container {
 
     selection_mode = SelectionMode.SINGLE;
 
-    children = new Sequence<ChildInfo?>();
-    child_hash = new HashTable<unowned Widget, unowned ChildInfo?> (GLib.direct_hash, GLib.direct_equal);
+    children = new Sequence<ChildInfo>();
+    child_hash = new HashTable<unowned Widget, unowned ChildInfo> (GLib.direct_hash, GLib.direct_equal);
   }
 
-  public Widget? get_selected_child (){
+  public unowned Widget? get_selected_child (){
     if (selected_child != null)
       return selected_child.widget;
 
@@ -64,7 +68,7 @@ public class Egg.ListBox : Container {
   public void select_child (Widget? child) {
     unowned ChildInfo? info = null;
     if (child != null)
-      info = child_hash.get (child);
+      info = lookup_info (child);
     update_selected (info);
   }
 
@@ -139,7 +143,7 @@ public class Egg.ListBox : Container {
 
   /****** Implementation ***********/
 
-  private int do_sort (ChildInfo? a, ChildInfo? b) {
+  private int do_sort (ChildInfo a, ChildInfo b) {
     return sort_func (a.widget, b.widget);
   }
 
@@ -172,7 +176,7 @@ public class Egg.ListBox : Container {
 	modify_selection_pressed = true;
     }
 
-    unowned ChildInfo? child = null;
+    ChildInfo? child = null;
     switch (step) {
     case MovementStep.BUFFER_ENDS:
       if (count < 0)
@@ -182,7 +186,7 @@ public class Egg.ListBox : Container {
       break;
     case MovementStep.DISPLAY_LINES:
       if (cursor_child != null) {
-	SequenceIter<ChildInfo?>? iter = cursor_child.iter;
+	SequenceIter<ChildInfo>? iter = cursor_child.iter;
 
 	while (count < 0 && iter != null) {
 	  iter = get_previous_visible (iter);
@@ -206,7 +210,7 @@ public class Egg.ListBox : Container {
       if (cursor_child != null) {
 	int start_y = cursor_child.y;
 	int end_y = start_y;
-	SequenceIter<ChildInfo?>? iter = cursor_child.iter;
+	SequenceIter<ChildInfo>? iter = cursor_child.iter;
 
 	child = cursor_child;
 	if (count < 0) {
@@ -216,7 +220,7 @@ public class Egg.ListBox : Container {
 	    iter = get_previous_visible (iter);
 	    if (iter == null)
 	      break;
-	    unowned ChildInfo? prev = iter.get ();
+	    ChildInfo prev = iter.get ();
 	    if (prev.y < start_y - page_size)
 	      break;
 	    child = prev;
@@ -228,7 +232,7 @@ public class Egg.ListBox : Container {
 	    iter = get_next_visible (iter);
 	    if (iter.is_end ())
 	      break;
-	    unowned ChildInfo? next = iter.get ();
+	    ChildInfo next = iter.get ();
 	    if (next.y > start_y + page_size)
 	      break;
 	    child = next;
@@ -314,7 +318,7 @@ public class Egg.ListBox : Container {
   unowned ChildInfo? find_child_at_y (int y) {
     unowned ChildInfo? child_info = null;
     for (var iter = children.get_begin_iter (); !iter.is_end (); iter = iter.next ()) {
-      unowned ChildInfo? info = iter.get ();
+      unowned ChildInfo info = iter.get ();
       if (y >= info.y && y < info.y + info.height) {
 	child_info = info;
 	break;
@@ -327,7 +331,7 @@ public class Egg.ListBox : Container {
     cursor_child = child;
     this.grab_focus ();
     this.queue_draw ();
-    var vadj = get_focus_vadjustment ();
+    unowned Adjustment? vadj = get_focus_vadjustment ();
     if (child != null && vadj != null)
       vadj.clamp_page (cursor_child.y,
 		       cursor_child.y + cursor_child.height);
@@ -345,7 +349,7 @@ public class Egg.ListBox : Container {
   }
 
   private void select_and_activate (ChildInfo? child) {
-    Widget? w = null;
+    unowned Widget? w = null;
     if (child != null)
       w = child.widget;
     update_selected (child);
@@ -431,7 +435,7 @@ public class Egg.ListBox : Container {
   public override bool focus (DirectionType direction) {
     bool had_focus;
     bool focus_into;
-    Widget recurse_into = null;
+    unowned Widget recurse_into = null;
 
     focus_into = true;
     had_focus = has_focus;
@@ -542,10 +546,10 @@ public class Egg.ListBox : Container {
   }
 
   private struct ChildFlags {
-    unowned ChildInfo? child;
+    unowned ChildInfo child;
     StateFlags state;
 
-    public static ChildFlags *find_or_add (ref ChildFlags[] array, ChildInfo? to_find) {
+    public static ChildFlags *find_or_add (ref ChildFlags[] array, ChildInfo to_find) {
       for (int i = 0; i < array.length; i++) {
 	if (array[i].child == to_find)
 	  return &array[i];
@@ -561,7 +565,7 @@ public class Egg.ListBox : Container {
     Allocation allocation;
     this.get_allocation (out allocation);
 
-    var context = this.get_style_context ();
+    unowned StyleContext context = this.get_style_context ();
 
     context.render_background (cr,
 			       0, 0, allocation.width, allocation.height);
@@ -638,14 +642,14 @@ public class Egg.ListBox : Container {
 
   private void apply_filter_all () {
     for (var iter = children.get_begin_iter (); !iter.is_end (); iter = iter.next ()) {
-      unowned ChildInfo? child_info = iter.get ();
+      unowned ChildInfo child_info = iter.get ();
       apply_filter (child_info.widget);
     }
   }
 
   private unowned ChildInfo? get_first_visible () {
     for (var iter = children.get_begin_iter (); !iter.is_end (); iter = iter.next ()) {
-      unowned ChildInfo? child_info = iter.get ();
+      unowned ChildInfo child_info = iter.get ();
       unowned Widget widget = child_info.widget;
       if (widget.get_visible () && widget.get_child_visible ())
 	return child_info;
@@ -657,7 +661,7 @@ public class Egg.ListBox : Container {
     var iter = children.get_end_iter ();
     while (!iter.is_begin ()) {
       iter = iter.prev ();
-      unowned ChildInfo? child_info = iter.get ();
+      unowned ChildInfo child_info = iter.get ();
       unowned Widget widget = child_info.widget;
       if (widget.get_visible () && widget.get_child_visible ())
 	return child_info;
@@ -665,7 +669,7 @@ public class Egg.ListBox : Container {
     return null;
   }
 
-  private SequenceIter<ChildInfo?>? get_previous_visible (SequenceIter<ChildInfo?> _iter) {
+  private SequenceIter<ChildInfo>? get_previous_visible (SequenceIter<ChildInfo> _iter) {
     if (_iter.is_begin())
       return null;
     var iter = _iter;
@@ -673,7 +677,7 @@ public class Egg.ListBox : Container {
     do {
       iter = iter.prev ();
 
-      unowned ChildInfo? child_info = iter.get ();
+      unowned ChildInfo child_info = iter.get ();
       unowned Widget widget = child_info.widget;
       if (widget.get_visible () && widget.get_child_visible ())
 	return iter;
@@ -682,7 +686,7 @@ public class Egg.ListBox : Container {
     return null;
   }
 
-  private SequenceIter<ChildInfo?>? get_next_visible (SequenceIter<ChildInfo?> _iter) {
+  private SequenceIter<ChildInfo>? get_next_visible (SequenceIter<ChildInfo> _iter) {
     if (_iter.is_end())
       return _iter;
 
@@ -691,7 +695,7 @@ public class Egg.ListBox : Container {
       iter = iter.next ();
 
       if (!iter.is_end ()) {
-	unowned ChildInfo? child_info = iter.get ();
+	unowned ChildInfo child_info = iter.get ();
 	unowned Widget widget = child_info.widget;
 	if (widget.get_visible () && widget.get_child_visible ())
 	  return iter;
@@ -701,16 +705,16 @@ public class Egg.ListBox : Container {
     return iter;
   }
 
-  private void update_separator (SequenceIter<ChildInfo?>? iter) {
+  private void update_separator (SequenceIter<ChildInfo>? iter) {
     if (iter == null || iter.is_end ())
       return;
 
-    unowned ChildInfo? info = iter.get ();
+    unowned ChildInfo info = iter.get ();
     var before_iter = get_previous_visible (iter);
     var widget = info.widget;
     Widget? before_widget = null;
     if (before_iter != null) {
-      unowned ChildInfo? before_info = before_iter.get ();
+      unowned ChildInfo before_info = before_iter.get ();
       before_widget = before_info.widget;
     }
 
@@ -740,16 +744,15 @@ public class Egg.ListBox : Container {
   }
 
   public override void add (Widget widget) {
-    ChildInfo? the_info = { widget };
-    unowned ChildInfo? info = the_info;
-    SequenceIter<ChildInfo?> iter;
+    ChildInfo info = new ChildInfo (widget);
+    SequenceIter<ChildInfo> iter;
 
     child_hash.set (widget, info);
 
     if (sort_func != null)
-      iter = children.insert_sorted ((owned) the_info, do_sort);
+      iter = children.insert_sorted (info, do_sort);
     else
-      iter = children.append ((owned) the_info);
+      iter = children.append (info);
 
     apply_filter (widget);
 
@@ -796,7 +799,7 @@ public class Egg.ListBox : Container {
   public override void forall_internal (bool include_internals,
 					Gtk.Callback callback) {
     for (var iter = children.get_begin_iter (); !iter.is_end (); iter = iter.next ()) {
-      unowned ChildInfo? child_info = iter.get ();
+      unowned ChildInfo child_info = iter.get ();
       if (child_info.separator != null && include_internals)
 	callback (child_info.separator);
       callback (child_info.widget);
@@ -825,12 +828,12 @@ public class Egg.ListBox : Container {
 
   public override void get_preferred_height_for_width (int width, out int minimum_height, out int natural_height) {
     minimum_height = 0;
-    var context = this.get_style_context ();
+    unowned StyleContext context = this.get_style_context ();
     int focus_width, focus_pad;
     context.get_style ("focus-line-width", out focus_width,
 		       "focus-padding", out focus_pad);
     for (var iter = children.get_begin_iter (); !iter.is_end (); iter = iter.next ()) {
-      unowned ChildInfo? child_info = iter.get ();
+      unowned ChildInfo child_info = iter.get ();
       unowned Widget widget = child_info.widget;
       int child_min;
 
@@ -856,14 +859,14 @@ public class Egg.ListBox : Container {
   }
 
   public override void get_preferred_width (out int minimum_width, out int natural_width) {
-    var context = this.get_style_context ();
+    unowned StyleContext context = this.get_style_context ();
     int focus_width, focus_pad;
     context.get_style ("focus-line-width", out focus_width,
 		       "focus-padding", out focus_pad);
     minimum_width = 0;
     natural_width = 0;
     for (var iter = children.get_begin_iter (); !iter.is_end (); iter = iter.next ()) {
-      unowned ChildInfo? child_info = iter.get ();
+      unowned ChildInfo child_info = iter.get ();
       unowned Widget widget = child_info.widget;
       int child_min, child_nat;
 
@@ -912,7 +915,7 @@ public class Egg.ListBox : Container {
     separator_allocation.width = allocation.width;
 
     for (var iter = children.get_begin_iter (); !iter.is_end (); iter = iter.next ()) {
-      unowned ChildInfo? child_info = iter.get ();
+      unowned ChildInfo child_info = iter.get ();
       unowned Widget widget = child_info.widget;
       int child_min;