Support nesting pseudo-classes like ":not" or ":is" (Less.js 4.2) #136
Description
Less.php 5.4 does not seem to process the following selector correctly:
.uk-form-small:is(.uk-input, .uk-search-input, .uk-select:not([multiple]):not([size])) {
height: 42px;
}The parser aborts with an error during compilation.
Expected behavior
The selector should be parsed correctly and compiled without errors.
Actual behavior
A parse error occurs although the CSS syntax is valid.