change let -> const if not reassigned, phetsims/tasks#973

js/HeaterCoolerBack.js

@@ -50,24 +50,24 @@ define( require => {
       }, options );
 
       // Dimensions for the rest of the stove, dependent on the desired stove width.
-      let burnerOpeningHeight = DEFAULT_WIDTH * OPENING_HEIGHT_SCALE;
+      const burnerOpeningHeight = DEFAULT_WIDTH * OPENING_HEIGHT_SCALE;
 
       // Create the inside bowl of the burner, which is an ellipse.
-      let burnerInteriorShape = new Shape()
+      const burnerInteriorShape = new Shape()
         .ellipse( DEFAULT_WIDTH / 2, burnerOpeningHeight / 4, DEFAULT_WIDTH / 2, burnerOpeningHeight / 2, 0, 0, Math.PI, false );
-      let burnerInterior = new Path( burnerInteriorShape, {
+      const burnerInterior = new Path( burnerInteriorShape, {
         stroke: 'black',
         fill: new LinearGradient( 0, 0, DEFAULT_WIDTH, 0 )
           .addColorStop( 0, options.baseColor.darkerColor( 0.5 ) )
           .addColorStop( 1, options.baseColor.brighterColor( 0.5 ) )
       } );
 
-      let fireNode = new Image( fireImage, {
+      const fireNode = new Image( fireImage, {
         centerX: burnerInterior.centerX,
         top: burnerInterior.bottom,
         scale: DEFAULT_WIDTH / DEFAULT_WIDTH
       } );
-      let iceNode = new Image( iceImage, {
+      const iceNode = new Image( iceImage, {
         centerX: burnerInterior.centerX,
         top: burnerInterior.bottom,
         scale: DEFAULT_WIDTH / DEFAULT_WIDTH

js/HeaterCoolerFront.js

@@ -69,32 +69,32 @@ define( require => {
 
       // Dimensions for the rest of the stove, dependent on the specified stove width.  Empirically determined, and could
       // be made into options if needed.
-      let height = DEFAULT_WIDTH * 0.75;
-      let burnerOpeningHeight = DEFAULT_WIDTH * HeaterCoolerBack.OPENING_HEIGHT_SCALE;
-      let bottomWidth = DEFAULT_WIDTH * 0.80;
+      const height = DEFAULT_WIDTH * 0.75;
+      const burnerOpeningHeight = DEFAULT_WIDTH * HeaterCoolerBack.OPENING_HEIGHT_SCALE;
+      const bottomWidth = DEFAULT_WIDTH * 0.80;
 
       // Create the body of the stove.
-      let stoveBodyShape = new Shape()
+      const stoveBodyShape = new Shape()
         .ellipticalArc( DEFAULT_WIDTH / 2, burnerOpeningHeight / 4, DEFAULT_WIDTH / 2, burnerOpeningHeight / 2, 0, 0, Math.PI, false )
         .lineTo( ( DEFAULT_WIDTH - bottomWidth ) / 2, height + burnerOpeningHeight / 2 )
         .ellipticalArc( DEFAULT_WIDTH / 2, height + burnerOpeningHeight / 4, bottomWidth / 2, burnerOpeningHeight,
           0, Math.PI, 0, true ).lineTo( DEFAULT_WIDTH, burnerOpeningHeight / 2 );
 
-      let stoveBody = new Path( stoveBodyShape, {
+      const stoveBody = new Path( stoveBodyShape, {
         stroke: 'black',
         fill: new LinearGradient( 0, 0, DEFAULT_WIDTH, 0 )
           .addColorStop( 0, options.baseColor.brighterColor( 0.5 ) )
           .addColorStop( 1, options.baseColor.darkerColor( 0.5 ) )
       } );
 
       // Create the label strings and scale them to support translations.
-      let titleOptions = { font: options.labelFont, maxWidth: options.labelMaxWidth };
-      let heatTitle = new Text( options.heatLabel, titleOptions );
-      let coolTitle = new Text( options.coolLabel, titleOptions );
-      let titles = [ heatTitle, coolTitle ];
+      const titleOptions = { font: options.labelFont, maxWidth: options.labelMaxWidth };
+      const heatTitle = new Text( options.heatLabel, titleOptions );
+      const coolTitle = new Text( options.coolLabel, titleOptions );
+      const titles = [ heatTitle, coolTitle ];
 
       // Scale the titles to fit within the bucket front if necessary.
-      let maxTitleWidth = Math.max( coolTitle.width, heatTitle.width );
+      const maxTitleWidth = Math.max( coolTitle.width, heatTitle.width );
       if ( maxTitleWidth > bottomWidth / 2 ) {
         titles.forEach( function( title ) {
           title.scale( ( bottomWidth / 2 ) / maxTitleWidth );

js/accessibility/UtteranceTests.js

@@ -14,7 +14,7 @@ define( require => {
   const Utterance = require( 'SCENERY_PHET/accessibility/Utterance' );
   const utteranceQueue = require( 'SCENERY_PHET/accessibility/utteranceQueue' );
 
-  var sleepTiming = null;
+  let sleepTiming = null;
 
   // helper es6 functions from  https://stackoverflow.com/questions/33289726/combination-of-async-function-await-settimeout/33292942
   function timeout( ms ) {
@@ -30,7 +30,7 @@ define( require => {
 
   var alerts = [];
 
-  var intervalID = null;
+  let intervalID = null;
   QUnit.module( 'Utterance', {
     before() {
 
@@ -67,12 +67,12 @@ define( require => {
 
     assert.ok( true, 'first test' );
 
-    let alert = 'hi';
-    utteranceQueue.addToBack( alert );
+    const myAlert = 'hi';
+    utteranceQueue.addToBack( myAlert );
 
 
     await sleep( () => {
-      assert.ok( alerts[ 0 ] === alert, 'basic utteranceQueue test' );
+      assert.ok( alerts[ 0 ] === myAlert, 'basic utteranceQueue test' );
     } );
 
     utteranceQueue.addToBack( 'alert' );
@@ -134,18 +134,18 @@ define( require => {
 
   QUnit.test( 'Utterance options', async assert => {
 
-    var alert = new Utterance( {
+    const alert = new Utterance( {
       alert: [ '1', '2', '3' ]
     } );
 
-    let alert4 = () => {
+    const alert4 = () => {
       utteranceQueue.addToBack( alert );
       utteranceQueue.addToBack( alert );
       utteranceQueue.addToBack( alert );
       utteranceQueue.addToBack( alert );
     };
 
-    let testOrder = ( messageSuffix ) => {
+    const testOrder = ( messageSuffix ) => {
 
       // newest at lowest index because of unshift
       assert.ok( alerts[ 3 ] === '1', 'Array order1' + messageSuffix );
@@ -165,12 +165,12 @@ define( require => {
 
   QUnit.test( 'Utterance loopAlerts', async assert => {
 
-    var alert = new Utterance( {
+    const alert = new Utterance( {
       alert: [ '1', '2', '3' ],
       loopAlerts: true
     } );
 
-    let alert7 = () => {
+    const alert7 = () => {
       utteranceQueue.addToBack( alert );
       utteranceQueue.addToBack( alert );
       utteranceQueue.addToBack( alert );
@@ -180,7 +180,7 @@ define( require => {
       utteranceQueue.addToBack( alert );
     };
 
-    let testOrder = ( messageSuffix ) => {
+    const testOrder = ( messageSuffix ) => {
 
       // newest at lowest index
       assert.ok( alerts[ 6 ] === '1', 'Array order1' + messageSuffix );

js/accessibility/describers/BorderAlertsDescriber.js

@@ -19,12 +19,12 @@ define( ( require ) => {
   const utteranceQueue = require( 'SCENERY_PHET/accessibility/utteranceQueue' );
 
   // a11y strings
-  let leftBorderAlertString = SceneryPhetA11yStrings.leftBorderAlert.value;
-  let rightBorderAlertString = SceneryPhetA11yStrings.rightBorderAlert.value;
-  let topBorderAlertString = SceneryPhetA11yStrings.topBorderAlert.value;
-  let bottomBorderAlertString = SceneryPhetA11yStrings.bottomBorderAlert.value;
+  const leftBorderAlertString = SceneryPhetA11yStrings.leftBorderAlert.value;
+  const rightBorderAlertString = SceneryPhetA11yStrings.rightBorderAlert.value;
+  const topBorderAlertString = SceneryPhetA11yStrings.topBorderAlert.value;
+  const bottomBorderAlertString = SceneryPhetA11yStrings.bottomBorderAlert.value;
 
-  let DEFAULT_TOP_BORDER_ALERT = topBorderAlertString;
+  const DEFAULT_TOP_BORDER_ALERT = topBorderAlertString;
 
   /**
    * Responsible for alerting when the temperature increases
@@ -68,7 +68,7 @@ define( ( require ) => {
     alertAtBorder( position, keyCode ) {
       let alertDirection;
 
-      let bordersTouching = [];
+      const bordersTouching = [];
 
       // at left now, but wasn't last location
       if ( position.x === this.bounds.left ) {
@@ -93,7 +93,7 @@ define( ( require ) => {
       // corner case
       if ( bordersTouching.length > 1 ) {
         keyCode = keyCode || -1;
-        let possibleDirection = DirectionEnum.keyCodeToDirection( keyCode );
+        const possibleDirection = DirectionEnum.keyCodeToDirection( keyCode );
 
         // if the keyCode matches a border direction, use that instead of another wall that we may also be touching
         if ( possibleDirection && bordersTouching.indexOf( possibleDirection ) >= 0 ) {
@@ -108,7 +108,7 @@ define( ( require ) => {
       // Then we are potentially going to alert
       if ( alertDirection ) {
         assert && assert( DirectionEnum.isRelativeDirection( alertDirection ), `unsupported direction: ${alertDirection}` );
-        let borderAlert = this[ alertDirection ];
+        const borderAlert = this[ alertDirection ];
         assert && assert( borderAlert instanceof BorderAlert, 'sanity check' );
 
         borderAlert.alert();
@@ -171,7 +171,7 @@ define( ( require ) => {
     getAlert() {
       let alert = this._alert;
       if ( Array.isArray( alert ) ) {
-        let index = Util.clamp( this._numberOfTimesAlerted, 0, alert.length - 1 );
+        const index = Util.clamp( this._numberOfTimesAlerted, 0, alert.length - 1 );
         alert = alert[ index ];
       }
       return alert;

js/accessibility/describers/DirectionEnum.js

@@ -15,7 +15,7 @@ define( function( require ) {
   const sceneryPhet = require( 'SCENERY_PHET/sceneryPhet' );
 
   // It is important that the key and value are the same, so that either way you can access the values of the enum.
-  let DirectionEnum = {
+  const DirectionEnum = {
     LEFT: 'LEFT',
     RIGHT: 'RIGHT',
     UP: 'UP',

js/accessibility/describers/MovementDescriber.js

@@ -22,20 +22,20 @@ define( require => {
   const utteranceQueue = require( 'SCENERY_PHET/accessibility/utteranceQueue' );
 
   // a11y strings
-  let downString = SceneryPhetA11yStrings.down.value;
-  let leftString = SceneryPhetA11yStrings.left.value;
-  let rightString = SceneryPhetA11yStrings.right.value;
-  let upString = SceneryPhetA11yStrings.up.value;
+  const downString = SceneryPhetA11yStrings.down.value;
+  const leftString = SceneryPhetA11yStrings.left.value;
+  const rightString = SceneryPhetA11yStrings.right.value;
+  const upString = SceneryPhetA11yStrings.up.value;
 
   // constants
   // in radians - threshold for diagonal movement is +/- 15 degrees from diagonals
-  let DIAGONAL_MOVEMENT_THRESHOLD = 15 * Math.PI / 180;
+  const DIAGONAL_MOVEMENT_THRESHOLD = 15 * Math.PI / 180;
 
   // mapping from alerting direction to the radian range that fills that space in the unit circle.
   // The diagnal directions take up the middle third of each quadrant, such that each "outside" third is in the range for
   // a relative (primary) direction. Therefore each diagonal direction is 1/9 of the Unit circle, and each primary direction
   // is 2/9 of the unit circle.
-  let DIRECTION_MAP = {
+  const DIRECTION_MAP = {
     UP: new Range( -3 * Math.PI / 4 + DIAGONAL_MOVEMENT_THRESHOLD, -Math.PI / 4 - DIAGONAL_MOVEMENT_THRESHOLD ),
     DOWN: new Range( Math.PI / 4 + DIAGONAL_MOVEMENT_THRESHOLD, 3 * Math.PI / 4 - DIAGONAL_MOVEMENT_THRESHOLD ),
     RIGHT: new Range( -Math.PI / 4 + DIAGONAL_MOVEMENT_THRESHOLD, Math.PI / 4 - DIAGONAL_MOVEMENT_THRESHOLD ),
@@ -48,15 +48,15 @@ define( require => {
     UP_RIGHT: new Range( -Math.PI / 4 - DIAGONAL_MOVEMENT_THRESHOLD, -Math.PI / 4 + DIAGONAL_MOVEMENT_THRESHOLD ),
     DOWN_RIGHT: new Range( Math.PI / 4 - DIAGONAL_MOVEMENT_THRESHOLD, Math.PI / 4 + DIAGONAL_MOVEMENT_THRESHOLD )
   };
-  let DIRECTION_MAP_KEYS = Object.keys( DIRECTION_MAP );
+  const DIRECTION_MAP_KEYS = Object.keys( DIRECTION_MAP );
 
   if ( assert ) {
     DIRECTION_MAP_KEYS.forEach( direction => {
       assert( DirectionEnum.keys.indexOf( direction ) >= 0, `unexpected direction: ${direction}. Keys should be the same as those in DirectionEnum` );
     } );
   }
 
-  let DEFAULT_MOVEMENT_ALERTS = {
+  const DEFAULT_MOVEMENT_ALERTS = {
     LEFT: leftString,
     RIGHT: rightString,
     UP: upString,
@@ -92,7 +92,7 @@ define( require => {
       if ( assert ) {
 
         for ( let i = 0; i < this.movementAlertKeys.length; i++ ) {
-          let key = this.movementAlertKeys[ i ];
+          const key = this.movementAlertKeys[ i ];
           assert( DirectionEnum.keys.indexOf( key ) >= 0, `unexpected key: ${key}. Keys should be the same as those in DirectionEnum` );
           assert( AlertableDef.isAlertableDef( options.movementAlerts[ key ] ) );
         }
@@ -158,10 +158,10 @@ define( require => {
      */
     alertDirectionalMovement() {
 
-      let newLocation = this.locationProperty.get();
+      const newLocation = this.locationProperty.get();
       if ( !newLocation.equals( this.lastAlertedLocation ) ) {
 
-        let directions = this.getDirections( newLocation, this.lastAlertedLocation );
+        const directions = this.getDirections( newLocation, this.lastAlertedLocation );
 
         // make sure that these alerts exist
         if ( assert ) {
@@ -185,9 +185,9 @@ define( require => {
     getDirections( pointA, pointB ) {
       let direction;
 
-      let dx = pointA.x - pointB.x;
-      let dy = pointA.y - pointB.y;
-      let angle = Math.atan2( dy, dx );
+      const dx = pointA.x - pointB.x;
+      const dy = pointA.y - pointB.y;
+      const angle = Math.atan2( dy, dx );
 
       // atan2 wraps around Math.PI, so special check for moving left from absolute value
       if ( DIRECTION_MAP.LEFT.contains( Math.abs( angle ) ) ) {
@@ -196,7 +196,7 @@ define( require => {
 
       // otherwise, angle will be in one of the ranges in DIRECTION_MAP
       for ( let i = 0; i < DIRECTION_MAP_KEYS.length; i++ ) {
-        let entry = DIRECTION_MAP[ DIRECTION_MAP_KEYS[ i ] ];
+        const entry = DIRECTION_MAP[ DIRECTION_MAP_KEYS[ i ] ];
         if ( entry.contains( angle ) ) {
           direction = DirectionEnum[ DIRECTION_MAP_KEYS[ i ] ];
           break;

js/accessibility/nodes/A11yGrabDragNode.js

@@ -153,7 +153,7 @@ define( require => {
       this.dragFocusHighlight.makeDashed();
 
       // if ever we update the node's focusHighlight, then update the grab button's too to keep in syn.
-      let onHighlightChange = () => {
+      const onHighlightChange = () => {
         this.dragFocusHighlight.setShape( this.grabFocusHighlight.shape );
       };
       this.grabFocusHighlight.highlightChangedEmitter.addListener( onHighlightChange );
@@ -212,7 +212,7 @@ define( require => {
       this.listenersForGrab = options.listenersForGrab.concat( grabButtonListener );
       node.addInputListener( grabButtonListener );
 
-      let dragDivListener = {
+      const dragDivListener = {
 
         // Release the draggable on 'enter' key, tracking that we have released the draggable with this key so that
         // we don't immediately catch the 'click' event while the enter key is down on the button