strong-trace/apply_changelist.js

StrongTrace Node.js Tracer

"use strict";

var inherits = require("util").inherits

module.exports = applyChangelist

function applyChangelist(content, changelist) {
  if (changelist.length === 0) {
    return content
  }

  changelist = changelist.sort(function (a, b) {
    // Sort by position, then pri (priority) in case of tie.
    return (a.pos == b.pos) ? b.pri - a.pri : b.pos - a.pos
  })

  // console.log(changelist)

  for (var i = 0; i < changelist.length; i++) {
    content = spliceIn(content, changelist[i])
  }
  return content
}

function spliceIn(content, change) {
  var prelude = content.slice(0, change.pos)
  var remove = change.remove || 0
  var after = content.slice(change.pos + remove)

  return prelude + change.insertion + after
}