orionsoft-react-scripts
Version:
Orionsoft Configuration and scripts for Create React App.
81 lines (67 loc) • 1.99 kB
JavaScript
/**
* @fileoverview Enforce img tag uses alt attribute.
* @author Ethan Cohen
*/
// ----------------------------------------------------------------------------
// Rule Definition
// ----------------------------------------------------------------------------
import { getProp, getPropValue, elementType } from 'jsx-ast-utils';
module.exports = {
meta: {
docs: {},
schema: [
{
oneOf: [
{ type: 'string' },
{
type: 'array',
items: {
type: 'string',
},
minItems: 1,
uniqueItems: true,
},
],
},
],
},
create: context => ({
JSXOpeningElement: (node) => {
const typeCheck = ['img'].concat(context.options[0]);
const nodeType = elementType(node);
// Only check 'img' elements and custom types.
if (typeCheck.indexOf(nodeType) === -1) {
return;
}
const roleProp = getProp(node.attributes, 'role');
const roleValue = getPropValue(roleProp);
const isPresentation = roleProp && typeof roleValue === 'string'
&& roleValue.toLowerCase() === 'presentation';
if (isPresentation) {
return;
}
const altProp = getProp(node.attributes, 'alt');
// Missing alt prop error.
if (altProp === undefined) {
context.report({
node,
message: `${nodeType} elements must have an alt prop or use role="presentation".`,
});
return;
}
// Check if alt prop is undefined.
const altValue = getPropValue(altProp);
const isNullValued = altProp.value === null; // <img alt />
if ((altValue && !isNullValued) || altValue === '') {
return;
}
// Undefined alt prop error.
context.report({
node,
message:
`Invalid alt value for ${nodeType}. \
Use alt="" or role="presentation" for presentational images.`,
});
},
}),
};