enable prefer const (#5113)

packages/babel-plugin-transform-class-properties/src/index.js

@@ -3,7 +3,7 @@ import nameFunction from "babel-helper-function-name";
 import template from "babel-template";
 
 export default function ({ types: t }) {
-  let findBareSupers = {
+  const findBareSupers = {
     Super(path) {
       if (path.parentPath.isCallExpression({ callee: path.node })) {
         this.push(path.parentPath);
@@ -11,7 +11,7 @@ export default function ({ types: t }) {
     }
   };
 
-  let referenceVisitor = {
+  const referenceVisitor = {
     ReferencedIdentifier(path) {
       if (this.scope.hasOwnBinding(path.node.name)) {
         this.collision = true;
@@ -45,12 +45,12 @@ export default function ({ types: t }) {
     visitor: {
       Class(path, state) {
         const buildClassProperty = state.opts.spec ? buildClassPropertySpec : buildClassPropertyNonSpec;
-        let isDerived = !!path.node.superClass;
+        const isDerived = !!path.node.superClass;
         let constructor;
-        let props = [];
-        let body = path.get("body");
+        const props = [];
+        const body = path.get("body");
 
-        for (let path of body.get("body")) {
+        for (const path of body.get("body")) {
           if (path.isClassProperty()) {
             props.push(path);
           } else if (path.isClassMethod({ kind: "constructor" })) {
@@ -60,7 +60,7 @@ export default function ({ types: t }) {
 
         if (!props.length) return;
 
-        let nodes = [];
+        const nodes = [];
         let ref;
 
         if (path.isClassExpression() || !path.node.id) {
@@ -72,15 +72,15 @@ export default function ({ types: t }) {
 
         let instanceBody = [];
 
-        for (let prop of props) {
-          let propNode = prop.node;
+        for (const prop of props) {
+          const propNode = prop.node;
           if (propNode.decorators && propNode.decorators.length > 0) continue;
 
           // In non-spec mode, all properties without values are ignored.
           // In spec mode, *static* properties without values are still defined (see below).
           if (!state.opts.spec && !propNode.value) continue;
 
-          let isStatic = propNode.static;
+          const isStatic = propNode.static;
 
           if (isStatic) {
             nodes.push(buildClassProperty(ref, propNode));
@@ -92,7 +92,7 @@ export default function ({ types: t }) {
 
         if (instanceBody.length) {
           if (!constructor) {
-            let newConstructor = t.classMethod("constructor", t.identifier("constructor"), [], t.blockStatement([]));
+            const newConstructor = t.classMethod("constructor", t.identifier("constructor"), [], t.blockStatement([]));
             if (isDerived) {
               newConstructor.params = [t.restElement(t.identifier("args"))];
               newConstructor.body.body.push(
@@ -107,18 +107,18 @@ export default function ({ types: t }) {
             [constructor] = body.unshiftContainer("body", newConstructor);
           }
 
-          let collisionState = {
+          const collisionState = {
             collision: false,
             scope: constructor.scope
           };
 
-          for (let prop of props) {
+          for (const prop of props) {
             prop.traverse(referenceVisitor, collisionState);
             if (collisionState.collision) break;
           }
 
           if (collisionState.collision) {
-            let initialisePropsRef = path.scope.generateUidIdentifier("initialiseProps");
+            const initialisePropsRef = path.scope.generateUidIdentifier("initialiseProps");
 
             nodes.push(t.variableDeclaration("var", [
               t.variableDeclarator(
@@ -137,9 +137,9 @@ export default function ({ types: t }) {
           //
 
           if (isDerived) {
-            let bareSupers = [];
+            const bareSupers = [];
             constructor.traverse(findBareSupers, bareSupers);
-            for (let bareSuper of bareSupers) {
+            for (const bareSuper of bareSupers) {
               bareSuper.insertAfter(instanceBody);
             }
           } else {
@@ -147,7 +147,7 @@ export default function ({ types: t }) {
           }
         }
 
-        for (let prop of props) {
+        for (const prop of props) {
           prop.remove();
         }
 
@@ -169,11 +169,11 @@ export default function ({ types: t }) {
         path.insertAfter(nodes);
       },
       ArrowFunctionExpression(path) {
-        let classExp = path.get("body");
+        const classExp = path.get("body");
         if (!classExp.isClassExpression()) return;
 
-        let body = classExp.get("body");
-        let members = body.get("body");
+        const body = classExp.get("body");
+        const members = body.get("body");
         if (members.some((member) => member.isClassProperty())) {
           path.ensureBlock();
         }