From e027f9771e34b4138ccc541ce3ba14e6316a8e40 Mon Sep 17 00:00:00 2001
From: Tom Payne <twpayne@gmail.com>
Date: Wed, 6 Mar 2013 17:53:32 +0100
Subject: [PATCH] Use a single, shared attribution for Stamen sources

This ensures that the attribution only appears once, even if multiple
Stamen layers are used in the same map.
---
 src/ol/source/stamensource.js | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/src/ol/source/stamensource.js b/src/ol/source/stamensource.js
index 6ea87b6ab4..a29ec962da 100644
--- a/src/ol/source/stamensource.js
+++ b/src/ol/source/stamensource.js
@@ -74,6 +74,16 @@ ol.source.StamenProviderConfig = {
 };
 
 
+/**
+ * @const {Array.<ol.Attribution>}
+ */
+ol.source.STAMEN_ATTRIBUTIONS = [new ol.Attribution(
+    'Map tiles by <a href="http://stamen.com">Stamen Design</a>, under ' +
+    '<a href="http://creativecommons.org/licenses/by/3.0">CC BY 3.0</a>. ' +
+    'Data by <a href="http://openstreetmap.org">OpenStreetMap</a>, under ' +
+    '<a href="http://creativecommons.org/licenses/by-sa/3.0">CC BY SA</a>.')];
+
+
 
 /**
  * @constructor
@@ -82,14 +92,6 @@ ol.source.StamenProviderConfig = {
  */
 ol.source.Stamen = function(options) {
 
-  var attribution = new ol.Attribution(
-      'Map tiles by <a href="http://stamen.com">Stamen Design</a>, ' +
-      'under ' +
-      '<a href="http://creativecommons.org/licenses/by/3.0">CC BY 3.0</a>. ' +
-      'Data by <a href="http://openstreetmap.org">OpenStreetMap</a>, ' +
-      'under ' +
-      '<a href="http://creativecommons.org/licenses/by-sa/3.0">CC BY SA</a>.');
-
   var i = options.layer.indexOf('-');
   var provider = i == -1 ? options.layer : options.layer.slice(0, i);
   goog.asserts.assert(provider in ol.source.StamenProviderConfig);
@@ -103,7 +105,7 @@ ol.source.Stamen = function(options) {
       layerConfig.extension;
 
   goog.base(this, {
-    attributions: [attribution],
+    attributions: ol.source.STAMEN_ATTRIBUTIONS,
     maxZoom: providerConfig.maxZoom,
     // FIXME uncomment the following when tilegrid supports minZoom
     //minZoom: providerConfig.minZoom,