src/options/tab-size.js
function(ast) {
    let value = this.value;

    ast.traverseByType('space', function(space) {
      space.content = space.content.replace(/\t/, value);
    });
  }
function(ast) {
    let value = this.value;

    ast.traverseByType('space', function(space) {
      space.content = space.content.replace(/\t/, value);
    });
  }
Processes tree node.

@param {node} ast