Function applySingleDataTransform

_benchmarks/sample_echarts.js:21446–21580

(transOption, upSourceList, infoForPrint, // If `pipeIndex` is null/undefined, no piped transform.
    pipeIndex)

    }

    function applySingleDataTransform(transOption, upSourceList, infoForPrint, // If `pipeIndex` is null/undefined, no piped transform.
    pipeIndex) {
      var errMsg = '';

      if (!upSourceList.length) {
        if ("development" !== 'production') {
          errMsg = 'Must have at least one upstream dataset.';
        }

        throwError(errMsg);
      }

      if (!isObject(transOption)) {
        if ("development" !== 'production') {
          errMsg = 'transform declaration must be an object rather than ' + typeof transOption + '.';
        }

        throwError(errMsg);
      }

      var transType = transOption.type;
      var externalTransform = externalTransformMap.get(transType);

      if (!externalTransform) {
        if ("development" !== 'production') {
          errMsg = 'Can not find transform on type "' + transType + '".';
        }

        throwError(errMsg);
      } // Prepare source


      var extUpSourceList = map(upSourceList, function (upSource) {
        return createExternalSource(upSource, externalTransform);
      });
      var resultList = normalizeToArray(externalTransform.transform({
        upstream: extUpSourceList[0],
        upstreamList: extUpSourceList,
        config: clone(transOption.config)
      }));

      if ("development" !== 'production') {
        if (transOption.print) {
          var printStrArr = map(resultList, function (extSource) {
            var pipeIndexStr = pipeIndex != null ? ' === pipe index: ' + pipeIndex : '';
            return ['=== dataset index: ' + infoForPrint.datasetIndex + pipeIndexStr + ' ===', '- transform result data:', makePrintable(extSource.data), '- transform result dimensions:', makePrintable(extSource.dimensions)].join('\n');
          }).join('\n');
          consoleLog(printStrArr);
        }
      }

      return map(resultList, function (result, resultIndex) {
        var errMsg = '';

        if (!isObject(result)) {
          if ("development" !== 'production') {
            errMsg = 'A transform should not return some empty results.';
          }