From b1973fcdf48ce7d4bbac7ce6da9dbc97a8ed9b87 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=89ric=20Lemoine?= <eric.lemoine@gmail.com>
Date: Wed, 19 Aug 2015 14:16:48 +0200
Subject: [PATCH] Render map when layer.setMap(map) called

---
 src/ol/layer/layer.js            |  7 +++-
 test/spec/ol/layer/layer.test.js | 67 ++++++++++++++++++++++----------
 2 files changed, 52 insertions(+), 22 deletions(-)

diff --git a/src/ol/layer/layer.js b/src/ol/layer/layer.js
index 2690dc4fa0..40e7052efd 100644
--- a/src/ol/layer/layer.js
+++ b/src/ol/layer/layer.js
@@ -161,8 +161,12 @@ ol.layer.Layer.prototype.handleSourcePropertyChange_ = function() {
  */
 ol.layer.Layer.prototype.setMap = function(map) {
   goog.events.unlistenByKey(this.mapPrecomposeKey_);
-  this.changed();
+  this.mapPrecomposeKey_ = null;
+  if (goog.isNull(map)) {
+    this.changed();
+  }
   goog.events.unlistenByKey(this.mapRenderKey_);
+  this.mapRenderKey_ = null;
   if (!goog.isNull(map)) {
     this.mapPrecomposeKey_ = goog.events.listen(
         map, ol.render.EventType.PRECOMPOSE, function(evt) {
@@ -173,6 +177,7 @@ ol.layer.Layer.prototype.setMap = function(map) {
         }, false, this);
     this.mapRenderKey_ = goog.events.listen(
         this, goog.events.EventType.CHANGE, map.render, false, map);
+    this.changed();
   }
 };
 
diff --git a/test/spec/ol/layer/layer.test.js b/test/spec/ol/layer/layer.test.js
index 3b0acfb108..72e1f12b84 100644
--- a/test/spec/ol/layer/layer.test.js
+++ b/test/spec/ol/layer/layer.test.js
@@ -578,30 +578,55 @@ describe('ol.layer.Layer', function() {
 
   });
 
-  describe('As overlay', function() {
+  describe('#setMap (unmanaged layer)', function() {
+    var map;
 
-    it('overlays the layer on the map', function() {
-      var map = new ol.Map({});
-      var layer = new ol.layer.Layer({
-        map: map
+    beforeEach(function() {
+      map = new ol.Map({});
+    });
+
+    describe('with map in constructor options', function() {
+      it('renders the layer', function() {
+        var layer = new ol.layer.Layer({
+          map: map
+        });
+        var frameState = {
+          layerStatesArray: [],
+          layerStates: {}
+        };
+        map.dispatchEvent(new ol.render.Event('precompose', map, null,
+            frameState, null, null));
+        expect(frameState.layerStatesArray.length).to.be(1);
+        var layerState = frameState.layerStatesArray[0];
+        expect(layerState.layer).to.equal(layer);
+        expect(frameState.layerStates[goog.getUid(layer)]).to.equal(layerState);
+      });
+    });
+
+    describe('setMap sequences', function() {
+      var mapRenderSpy;
+
+      beforeEach(function() {
+        mapRenderSpy = sinon.spy(map, 'render');
+      });
+
+      afterEach(function() {
+        mapRenderSpy.restore();
+      });
+
+      it('requests a render frame', function() {
+        var layer = new ol.layer.Layer({});
+
+        layer.setMap(map);
+        expect(mapRenderSpy.callCount).to.be(1);
+
+        layer.setMap(null);
+        expect(mapRenderSpy.callCount).to.be(2);
+
+        layer.setMap(map);
+        expect(mapRenderSpy.callCount).to.be(3);
       });
-      var frameState = {
-        layerStatesArray: [],
-        layerStates: {}
-      };
-      map.dispatchEvent(new ol.render.Event('precompose', map, null,
-          frameState, null, null));
-      expect(frameState.layerStatesArray.length).to.be(1);
-      var layerState = frameState.layerStatesArray[0];
-      expect(layerState.layer).to.equal(layer);
-      expect(frameState.layerStates[goog.getUid(layer)]).to.equal(layerState);
-      frameState.layerStatesArray = [];
-      frameState.layerStates = {};
 
-      layer.setMap(null);
-      map.dispatchEvent(new ol.render.Event('precompose', map, null,
-          frameState, null, null));
-      expect(frameState.layerStatesArray.length).to.be(0);
     });
 
   });