[libgee] Use non-nullable capacities and a constant to specify unbounded

[Didier 'Ptitjes' Villevalois <dvillevalois src gnome org>]

commit 9f3357676f93569deef4eec486f942e462df5da2
Author: Didier 'Ptitjes <ptitjes free fr>
Date:   Mon Sep 14 18:34:09 2009 +0200

    Use non-nullable capacities and a constant to specify unbounded

 gee/linkedlist.vala  |    8 ++++----
 gee/queue.vala       |   12 +++++++++---
 tests/testqueue.vala |    4 ++--
 3 files changed, 15 insertions(+), 9 deletions(-)
---
diff --git a/gee/linkedlist.vala b/gee/linkedlist.vala
index 7b4775f..802a278 100644
--- a/gee/linkedlist.vala
+++ b/gee/linkedlist.vala
@@ -246,15 +246,15 @@ public class Gee.LinkedList<G> : AbstractList<G>, Queue<G>, Deque<G> {
 	/**
 	 * @inheritDoc
 	 */
-	public int? capacity {
-		get { return null; }
+	public int capacity {
+		get { return UNBOUNDED_CAPACITY; }
 	}
 
 	/**
 	 * @inheritDoc
 	 */
-	public int? remaining_capacity {
-		get { return null; }
+	public int remaining_capacity {
+		get { return UNBOUNDED_CAPACITY; }
 	}
 
 	/**
diff --git a/gee/queue.vala b/gee/queue.vala
index 321479b..cc67e56 100644
--- a/gee/queue.vala
+++ b/gee/queue.vala
@@ -26,7 +26,7 @@
  * Although all Queue implementations do not limit the amount of elements they
  * can contain, this interface supports for capacity-bounded queues. When
  * capacity is not bound, then the { link capacity} and
- * { link remaining_capacity} both return null.
+ * { link remaining_capacity} both return { link UNBOUNDED_CAPACITY}.
  *
  * This interface defines methods that will never fail whatever the state of
  * the queue is. For capacity-bounded queues, those methods will either return
@@ -44,15 +44,21 @@
  * poll method to indicate that the queue contains no elements.
  */
 public interface Gee.Queue<G> : Collection<G> {
+
+	/**
+	 * The unbounded capacity value.
+	 */
+	public static const int UNBOUNDED_CAPACITY = -1;
+
 	/**
 	 * The capacity of this queue (or null if capacity is not bound).
 	 */
-	public abstract int? capacity { get; }
+	public abstract int capacity { get; }
 
 	/**
 	 * The remaining capacity of this queue (or null if capacity is not bound).
 	 */
-	public abstract int? remaining_capacity { get; }
+	public abstract int remaining_capacity { get; }
 
 	/**
 	 * Specifies whether this queue is full.
diff --git a/tests/testqueue.vala b/tests/testqueue.vala
index e872084..86833ae 100644
--- a/tests/testqueue.vala
+++ b/tests/testqueue.vala
@@ -36,9 +36,9 @@ public abstract class QueueTests : CollectionTests {
 		// Check the test queue is not null
 		assert (test_queue != null);
 
-		if (test_queue.capacity == null) {
+		if (test_queue.capacity == Gee.Queue.UNBOUNDED_CAPACITY) {
 			// Unbounded capacity
-			assert (test_queue.remaining_capacity == null);
+			assert (test_queue.remaining_capacity == Gee.Queue.UNBOUNDED_CAPACITY);
 			assert (! test_queue.is_full);
 		} else {
 			// Bounded capacity