Fix #3192 setting the default layer as object (#3199)

web/client/reducers/__tests__/layers-test.js

@@ -12,6 +12,11 @@ const { changeLayerParams } = require('../../actions/layers');
 
 describe('Test the layers reducer', () => {
 
+    it('confirms that the default state is an object with "flat" as a property', () => {
+        let state = layers(undefined, {type: 'UNKNOWN'});
+        expect(state.flat.length).toBe(0);
+    });
+
     it('returns original state on unrecognized action', () => {
         let state = layers(1, {type: 'UNKNOWN'});
         expect(state).toBe(1);

web/client/reducers/layers.js

@@ -57,7 +57,7 @@ const moveNode = (groups, node, groupId, newLayers, foreground = true) => {
     return LayersUtils.removeEmptyGroups(newGroups);
 };
 
-function layers(state = [], action) {
+function layers(state = { flat: [] }, action) {
     switch (action.type) {
         case TOGGLE_CONTROL: {
             if (action.control === 'RefreshLayers') {

web/client/selectors/__tests__/automapupdate-test.js

@@ -8,6 +8,7 @@
 
 const expect = require('expect');
 const {getWMSLayers, refreshingLayers} = require('../automapupdate');
+const reducer = require('../../reducers/layers');
 
 const state = {
     layers: {
@@ -35,4 +36,11 @@ describe('Test automapupdate selectors', () => {
 
         expect(layers.length).toBe(1);
     });
+
+    it('getWMSLayers works with initial state', () => {
+        const emptyState = {
+            layers: reducer(undefined, { type: "TEST" })
+        };
+        expect(getWMSLayers(emptyState).length).toBe(0);
+    });
 });