How to use the zrender/src/core/util.merge function in zrender

completeVisualOption: function () {
        var ecModel = this.ecModel;
        var thisOption = this.option;
        var base = {inRange: thisOption.inRange, outOfRange: thisOption.outOfRange};

        var target = thisOption.target || (thisOption.target = {});
        var controller = thisOption.controller || (thisOption.controller = {});

        zrUtil.merge(target, base); // Do not override
        zrUtil.merge(controller, base); // Do not override

        var isCategory = this.isCategory();

        completeSingle.call(this, target);
        completeSingle.call(this, controller);
        completeInactive.call(this, target, 'inRange', 'outOfRange');
        // completeInactive.call(this, target, 'outOfRange', 'inRange');
        completeController.call(this, controller);

        function completeSingle(base) {
            // Compatible with ec2 dataRange.color.
            // The mapping order of dataRange.color is: [high value, ..., low value]
            // whereas inRange.color and outOfRange.color is [low value, ..., high value]
            // Notice: ec2 has no inverse.
            if (isArray(thisOption.color)

function mergeNewElOptionToExist(existList, index, newElOption) {
  // Update existing options, for `getOption` feature.
  var newElOptCopy = zrUtil.extend({}, newElOption);
  var existElOption = existList[index];
  var $action = newElOption.$action || 'merge';

  if ($action === 'merge') {
    if (existElOption) {
      // We can ensure that newElOptCopy and existElOption are not
      // the same object, so `merge` will not change newElOptCopy.
      zrUtil.merge(existElOption, newElOptCopy, true); // Rigid body, use ignoreSize.

      layoutUtil.mergeLayoutParam(existElOption, newElOptCopy, {
        ignoreSize: true
      }); // Will be used in render.

      layoutUtil.copyLayoutParams(newElOption, existElOption);
    } else {
      existList[index] = newElOptCopy;
    }
  } else if ($action === 'replace') {
    existList[index] = newElOptCopy;
  } else if ($action === 'remove') {
    // null will be cleaned later.
    existElOption && (existList[index] = null);
  }
}

// parallelIndex: null,

    areaSelectStyle: {
        width: 20,
        borderWidth: 1,
        borderColor: 'rgba(160,197,232)',
        color: 'rgba(160,197,232)',
        opacity: 0.3
    },

    realtime: true, // Whether realtime update view when select.

    z: 10
};

zrUtil.merge(AxisModel.prototype, axisModelCommonMixin);

function getAxisType(axisName, option) {
    return option.type || (option.data ? 'category' : 'value');
}

axisModelCreator('parallel', AxisModel, getAxisType, defaultOption);

export default AxisModel;

mergeDefaultAndTheme: function (option, ecModel) {
    var layoutMode = this.layoutMode;
    var inputPositionParams = layoutMode ? getLayoutParams(option) : {}; // Backward compat: using subType on theme.
    // But if name duplicate between series subType
    // (for example: parallel) add component mainType,
    // add suffix 'Series'.

    var themeSubType = this.subType;

    if (ComponentModel.hasClass(themeSubType)) {
      themeSubType += 'Series';
    }

    zrUtil.merge(option, ecModel.getTheme().get(this.subType));
    zrUtil.merge(option, this.getDefaultOption()); // Default label emphasis `show`

    modelUtil.defaultEmphasis(option, 'label', ['show']);
    this.fillDataTextStyle(option.data);

    if (layoutMode) {
      mergeLayoutParam(option, inputPositionParams, layoutMode);
    }
  },
  mergeOption: function (newSeriesOption, ecModel) {

this._componentsMap = createHashMap({series: []});

    /**
     * Mapping between filtered series list and raw series list.
     * key: filtered series indices, value: raw series indices.
     * @type {Array.}
     * @private
     */
    this._seriesIndices;

    this._seriesIndicesMap;

    mergeTheme(baseOption, this._theme.option);

    // TODO Needs clone when merging to the unexisted property
    merge(baseOption, globalDefault, false);

    this.mergeOption(baseOption);
}

mergeOption: function (newOption) {
        var inputRawOption = retrieveRawOption(newOption);

        //FIX #2591
        zrUtil.merge(this.option, newOption, true);
        zrUtil.merge(this.settledOption, inputRawOption, true);

        this.doInit(inputRawOption);
    },

if (!opt[styleName].normal) {
        opt[styleName].normal = normalItemStyleOpt[styleName];
      } else {
        zrUtil.merge(opt[styleName].normal, normalItemStyleOpt[styleName]);
      }

      normalItemStyleOpt[styleName] = null;
    }

    if (emphasisItemStyleOpt && emphasisItemStyleOpt[styleName]) {
      opt[styleName] = opt[styleName] || {};

      if (!opt[styleName].emphasis) {
        opt[styleName].emphasis = emphasisItemStyleOpt[styleName];
      } else {
        zrUtil.merge(opt[styleName].emphasis, emphasisItemStyleOpt[styleName]);
      }

      emphasisItemStyleOpt[styleName] = null;
    }
  }
}

mergeDefaultAndTheme: function (option, ecModel) {
    var layoutMode = this.layoutMode;
    var inputPositionParams = layoutMode ? layout.getLayoutParams(option) : {};
    var themeModel = ecModel.getTheme();
    zrUtil.merge(option, themeModel.get(this.mainType));
    zrUtil.merge(option, this.getDefaultOption());

    if (layoutMode) {
      layout.mergeLayoutParam(option, inputPositionParams, layoutMode);
    }
  },
  mergeOption: function (option, extraOpt) {

dataParams.axisDim = item.axisDim;
                    dataParams.axisIndex = item.axisIndex;
                    dataParams.axisType = item.axisType;
                    dataParams.axisId = item.axisId;
                    dataParams.axisValue = axisHelper.getAxisRawValue(axisModel.axis, axisValue);
                    dataParams.axisValueLabel = valueLabel;

                    if (dataParams) {
                        singleParamsList.push(dataParams);
                        var seriesTooltip = series.formatTooltip(dataIndex, true, null, renderMode);

                        var html;
                        if (zrUtil.isObject(seriesTooltip)) {
                            html = seriesTooltip.html;
                            var newMarkers = seriesTooltip.markers;
                            zrUtil.merge(markers, newMarkers);
                        }
                        else {
                            html = seriesTooltip;
                        }
                        seriesDefaultHTML.push(html);
                    }
                });

zrUtil.each(this.option.feature, function (featureOpt, featureName) {
      var Feature = featureManager.get(featureName);
      Feature && zrUtil.merge(featureOpt, Feature.defaultOption);
    });
  },