add-unit-true-to-ember-tests.js

// USAGE:
// 
// This script is supposed to be used with `jscodeshift`. Here is how you would invoke it:
//   $ jscodeshift -t add-unit-true-to-ember-tests.js --fn=moduleForComponent path/to/unit/tests/
//
// The `--fn` argument above can be changed to `moduleFor`, `moduleForModel`, etc.

module.exports = function transform(file, api, options) {
  var j = api.jscodeshift;
  var fn = options.fn || 'moduleForComponent';
  var affected = false;

  function shouldAddUnit(obj) {
    return obj.properties.every(p => p.key.name !== 'unit' && p.key.name !== 'needs');
  }

  function addUnitToObject(obj) {
    if (shouldAddUnit(obj)) {
      obj.properties.unshift(j.property('init', j.identifier('unit'), j.literal(true)));
      return true;
    }
  }

  function transformCall(call) {
    var args = call.value.arguments;
    var obj = null;

    for (var i = 0; i < args.length; i++) {
      if (j.ObjectExpression.check(args[i])) {
        obj = args[i];
        break;
      }
    }

    if (!obj) {
      obj = j.objectExpression([]);
      args.push(obj);
    }

    if (addUnitToObject(obj)) {
      affected = true;
    }
    return call;
  }

  function forceReprint(path) {
    path.node.original = null;
  }


  const transformed =
    j(file.source)
    .find(j.CallExpression, { callee: { name: fn } })
    .forEach(transformCall)
    .toSource({ trailingComma: true, wrapColumn: 120 });

  if (affected) {
    // Remove trailing comma from function calls. This won't be necessary after this issue is closed
    // https://github.com/benjamn/recast/issues/335
    return j(transformed)
      .find(j.CallExpression, { callee: { name: fn } })
      .forEach(forceReprint)
      .toSource({ trailingComma: false, wrapColumn: 120 });
  } else {
    return transformed;
  }
};