Function nativeTestProps

src/nativeTestProps.js:14–39

(props, value)

  // Accepts a list of property names and a single value
  // Returns `undefined` if native detection not available
  function nativeTestProps(props, value) {
    var i = props.length;
    // Start with the JS API: https://www.w3.org/TR/css3-conditional/#the-css-interface
    if ('CSS' in window && 'supports' in window.CSS) {
      // Try every prefixed variant of the property
      while (i--) {
        if (window.CSS.supports(domToCSS(props[i]), value)) {
          return true;
        }
      }
      return false;
    }
    // Otherwise fall back to at-rule (for Opera 12.x)
    else if ('CSSSupportsRule' in window) {
      // Build a condition string for every prefixed variant
      var conditionText = [];
      while (i--) {
        conditionText.push('(' + domToCSS(props[i]) + ':' + value + ')');
      }
      conditionText = conditionText.join(' or ');
      return injectElementWithStyles('@supports (' + conditionText + ') { #modernizr { position: absolute; } }', function(node) {
        return computedStyle(node, null, 'position') === 'absolute';
      });
    }
    return undefined;
  }
  return nativeTestProps;
});