mayHaveAccessibleLabel.js 2.67 KB
"use strict";

var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports["default"] = mayHaveAccessibleLabel;

var _arrayIncludes = _interopRequireDefault(require("array-includes"));

var _jsxAstUtils = require("jsx-ast-utils");

/**
 * Returns true if a labelling element is found or if it cannot determine if
 * a label is present because of expression containers or spread attributes.
 * A false return value means that the node definitely does not have a label,
 * but a true return return value means that the node may or may not have a
 * label.
 *
 * 
 */
function hasLabellingProp(openingElement) {
  var additionalLabellingProps = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : [];
  var labellingProps = [].concat('alt', // Assume alt is used correctly on an image
  'aria-label', 'aria-labelledby', additionalLabellingProps);
  return openingElement.attributes.some(function (attribute) {
    // We must assume that a spread value contains a labelling prop.
    if (attribute.type !== 'JSXAttribute') {
      return true;
    } // Attribute matches.


    if ((0, _arrayIncludes["default"])(labellingProps, (0, _jsxAstUtils.propName)(attribute)) && !!(0, _jsxAstUtils.getPropValue)(attribute)) {
      return true;
    }

    return false;
  });
}

function mayHaveAccessibleLabel(root) {
  var maxDepth = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 1;
  var additionalLabellingProps = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : [];

  function checkElement(node, depth) {
    // Bail when maxDepth is exceeded.
    if (depth > maxDepth) {
      return false;
    } // Check for literal text.


    if (node.type === 'Literal' && !!node.value) {
      return true;
    } // Assume an expression container renders a label. It is the best we can
    // do in this case.


    if (node.type === 'JSXExpressionContainer') {
      return true;
    } // Check for JSXText.
    // $FlowFixMe Remove after updating ast-types-flow


    if (node.type === 'JSXText' && !!node.value) {
      return true;
    } // Check for labelling props.


    if (node.openingElement
    /* $FlowFixMe */
    && hasLabellingProp(node.openingElement, additionalLabellingProps)) {
      return true;
    } // Recurse into the child element nodes.


    if (node.children) {
      /* $FlowFixMe */
      for (var i = 0; i < node.children.length; i += 1) {
        /* $FlowFixMe */
        if (checkElement(node.children[i], depth + 1)) {
          return true;
        }
      }
    }

    return false;
  }

  return checkElement(root, 0);
}

module.exports = exports.default;