Enable no-implicit-coercion eslint rule for strings

.eslintrc

@@ -43,6 +43,7 @@
         "no-extra-label": "error",
         "no-floating-decimal": "error",
         "no-global-assign": "error",
+        "no-implicit-coercion": ["warn", { "boolean": false, "number": false }],
         "no-implied-eval": "error",
         "no-invalid-this": "off",
         "no-iterator": "error",

modules/osm/note.js

@@ -37,7 +37,7 @@ Object.assign(osmNote.prototype, {
         }
 
         if (!this.id) {
-            this.id = osmNote.id() + '';  // as string
+            this.id = osmNote.id().toString();
         }
 
         return this;

modules/services/streetside.js

@@ -479,7 +479,8 @@ export default {
     if (!window.pannellum) return;
     if (_pannellumViewer) return;
 
-    const sceneID = ++_currScene + '';
+    _currScene += 1;
+    const sceneID = _currScene.toString();
     const options = {
       'default': { firstScene: sceneID },
       scenes: {}
@@ -873,14 +874,15 @@ export default {
           that.initViewer();
         } else {
           // make a new scene
-          let sceneID = ++_currScene + '';
+          _currScene += 1;
+          let sceneID = _currScene.toString();
           _pannellumViewer
             .addScene(sceneID, _sceneOptions)
             .loadScene(sceneID);
 
           // remove previous scene
           if (_currScene > 2) {
-            sceneID = (_currScene - 1) + '';
+            sceneID = (_currScene - 1).toString();
             _pannellumViewer
               .removeScene(sceneID);
           }

modules/ui/sections/validation_rules.js

@@ -121,7 +121,7 @@ export function uiSectionValidationRules(context) {
         // user-configurable square threshold
         var degStr = prefs('validate-square-degrees');
         if (degStr === null) {
-            degStr = '' + DEFAULTSQUARE;
+            degStr = DEFAULTSQUARE.toString();
         }
 
         var span = items.selectAll('.square-degrees');
@@ -132,8 +132,8 @@ export function uiSectionValidationRules(context) {
         input.enter()
             .append('input')
             .attr('type', 'number')
-            .attr('min', '' + MINSQUARE)
-            .attr('max', '' + MAXSQUARE)
+            .attr('min', MINSQUARE.toString())
+            .attr('max', MAXSQUARE.toString())
             .attr('step', '0.5')
             .attr('class', 'square-degrees-input')
             .call(utilNoAuto)
@@ -167,7 +167,7 @@ export function uiSectionValidationRules(context) {
         }
 
         degNum = Math.round(degNum * 10 ) / 10;   // round to 1 decimal
-        degStr = '' + degNum;
+        degStr = degNum.toString();
 
         input
             .property('value', degStr);