Function getNormalizationType

static/vuejs/vue.common.js:8765–8783

(children)

// 1: simple normalization needed (possible 1-level deep nested array)
// 2: full normalization needed
function getNormalizationType (children) {
  var res = 0;
  for (var i = 0; i < children.length; i++) {
    var el = children[i];
    if (el.type !== 1) {
      continue
    }
    if (needsNormalization(el) ||
        (el.ifConditions && el.ifConditions.some(function (c) { return needsNormalization(c.block); }))) {
      res = 2;
      break
    }
    if (maybeComponent(el) ||
        (el.ifConditions && el.ifConditions.some(function (c) { return maybeComponent(c.block); }))) {
      res = 1;
    }
  }
  return res
}

function needsNormalization (el) {
  return el.for !== undefined || el.tag === 'template' || el.tag === 'slot'