[fix] - Fix img-redundant-alt rule to use getLiteralPropValue.

Author: Ethan Cohen

src/rules/img-redundant-alt.js

@@ -7,7 +7,7 @@
 // Rule Definition
 // ----------------------------------------------------------------------------
 
-import { getProp, getPropValue, elementType } from 'jsx-ast-utils';
+import { getProp, getLiteralPropValue, elementType } from 'jsx-ast-utils';
 import isHiddenFromScreenReader from '../util/isHiddenFromScreenReader';
 
 const REDUNDANT_WORDS = [
@@ -20,11 +20,6 @@ const errorMessage = 'Redundant alt attribute. Screen-readers already announce '
   '`img` tags as an image. You don\'t need to use the words `image`, ' +
   '`photo,` or `picture` in the alt prop.';
 
-const validTypes = [
-  'LITERAL',
-  'TEMPLATELITERAL',
-];
-
 module.exports = context => ({
   JSXOpeningElement: node => {
     const type = elementType(node);
@@ -38,20 +33,10 @@ module.exports = context => ({
       return;
     }
 
-    // Only check literals, as we should not enforce variable names :P
-    const normalizedType = altProp.value &&
-      altProp.value.type.toUpperCase() === 'JSXEXPRESSIONCONTAINER' ?
-      altProp.value.expression.type.toUpperCase() :
-      altProp.value.type.toUpperCase();
-
-    if (validTypes.indexOf(normalizedType) === -1) {
-      return;
-    }
-
-    const value = getPropValue(altProp);
+    const value = getLiteralPropValue(altProp);
     const isVisible = isHiddenFromScreenReader(type, node.attributes) === false;
 
-    if (Boolean(value) && typeof value === 'string' && isVisible) {
+    if (typeof value === 'string' && isVisible) {
       const hasRedundancy = REDUNDANT_WORDS
         .some(word => Boolean(value.match(new RegExp(`(?!{)${word}(?!})`, 'gi'))));
 

tests/src/rules/img-redundant-alt.js

@@ -55,6 +55,7 @@ ruleTester.run('img-redundant-alt', rule, {
     { code: '<img aria-hidden={false} alt="Doing cool things." />', parserOptions },
     { code: '<UX.Layout>test</UX.Layout>', parserOptions },
     { code: '<img alt={imageAlt} />', parserOptions },
+    { code: '<img alt />', parserOptions },
   ],
   invalid: [
     { code: '<img alt="Photo of friend." />;', errors: [expectedError], parserOptions },