stylus/lib/nodes/ident.js

Robust, expressive, and feature-rich CSS superset

/*!
 * Stylus - Ident
 * Copyright (c) Automattic <developer.wordpress.com>
 * MIT Licensed
 */

/**
 * Module dependencies.
 */

var Node = require('./node')
  , nodes = require('./');

module.exports = class Ident extends Node {
  /**
   * Initialize a new `Ident` by `name` with the given `val` node.
   *
   * @param {String} name
   * @param {Node} val
   * @api public
   */

  constructor(name, val, mixin) {
    super();
    this.name = name;
    this.string = name;
    this.val = val || nodes.null;
    this.mixin = !!mixin;
  }

  /**
   * Check if the variable has a value.
   *
   * @return {Boolean}
   * @api public
   */

  get isEmpty() {
    return undefined == this.val;
  };

  /**
   * Return hash.
   *
   * @return {String}
   * @api public
   */

  get hash() {
    return this.name;
  };

  /**
   * Return a clone of this node.
   * 
   * @return {Node}
   * @api public
   */

  clone(parent) {
    var clone = new Ident(this.name);
    clone.val = this.val.clone(parent, clone);
    clone.mixin = this.mixin;
    clone.lineno = this.lineno;
    clone.column = this.column;
    clone.filename = this.filename;
    clone.property = this.property;
    clone.rest = this.rest;
    return clone;
  };

  /**
   * Return a JSON representation of this node.
   *
   * @return {Object}
   * @api public
   */

  toJSON() {
    return {
      __type: 'Ident',
      name: this.name,
      val: this.val,
      mixin: this.mixin,
      property: this.property,
      rest: this.rest,
      lineno: this.lineno,
      column: this.column,
      filename: this.filename
    };
  };

  /**
   * Return <name>.
   *
   * @return {String}
   * @api public
   */

  toString() {
    return this.name;
  };

  /**
   * Coerce `other` to an ident.
   *
   * @param {Node} other
   * @return {String}
   * @api public
   */

  coerce(other) {
    switch (other.nodeName) {
      case 'ident':
      case 'string':
      case 'literal':
        return new Ident(other.string);
      case 'unit':
        return new Ident(other.toString());
      default:
        return super.coerce(other);
    }
  };

  /**
   * Operate on `right` with the given `op`.
   *
   * @param {String} op
   * @param {Node} right
   * @return {Node}
   * @api public
   */

  operate(op, right) {
    var val = right.first;
    switch (op) {
      case '-':
        if ('unit' == val.nodeName) {
          var expr = new nodes.Expression;
          val = val.clone();
          val.val = -val.val;
          expr.push(this);
          expr.push(val);
          return expr;
        }
      case '+':
        return new nodes.Ident(this.string + this.coerce(val).string);
    }
    return super.operate(op, right);
  };
};