[Bug] getInitialData function may return uncatched undefined

[JuNe98]

Version

5.5.0

Link to Minimal Reproduction

https://echarts.apache.org/examples/en/editor.html?c=sankey-simple&code=PYBwLglsB2AEC8sDeAoWsDOBTAThLGAXMmurGAJ4hbEDkGAhtANZYW0A0p6ANgxcACuYOtBhZO3WFgC2IABYMMEIiTJkAZsADGg1bQYATAFYNtWaNvZSAvl3WGGYBsUHRDWDRGhZD9sjzezKoA2lLoqOrqGEI45nQMklFkzjgA5lgisAYAjEnJsABuDDyCNLAArOGwdtWRBTGCceUG-cmpGVkGAExtUcWl5QDM1bXJ9cmNzXQARn3qHZmzef7JA2XEAByjq2QTUVPx2Ym7CwzpS9kzK9Xo68M7dbeYsUe01_Mp550JNwVFJQ2sByj3Gz0OLQ-py-Fy62k-d0B5W6oykAF1SDYUDYANxAA

Steps to Reproduce

If your sankey diagram options doesn't contain data and links attribute the return of the getInitialData will be undefined and so the wrapData function will throw an error.

Current Behavior

If you set data and links in a sankey diagram to undefined you will get an error:

TypeError: Cannot read properties of undefined (reading 'CHANGABLE_METHODS')
    at wrapData (Series.js:512:39)
    at SeriesModel2.mergeOption (Series.js:145:5)
    at GlobalModel2.<anonymous> (Global.js:321:28)
    at Array.forEach (<anonymous>)
    at each (util.js:171:9)
    at GlobalModel2.visitComponent (Global.js:272:7)
    at entity.topologicalTravel (component.js:109:18)
    at GlobalModel2._mergeOption (Global.js:251:20)
    at GlobalModel2._resetOption (Global.js:181:14)
    at GlobalModel2.setOption (Global.js:157:10)

This error is the result of the getInitialData function in the SankeySeries.ts file at line 175.

 /**
     * Init a graph data structure from data in option series
     */
    getInitialData(option: SankeySeriesOption, ecModel: GlobalModel) {
        const links = option.edges || option.links;
        const nodes = option.data || option.nodes;
        const levels = option.levels;
        this.levelModels = [];
        const levelModels = this.levelModels;

        for (let i = 0; i < levels.length; i++) {
            if (levels[i].depth != null && levels[i].depth >= 0) {
                levelModels[levels[i].depth] = new Model(levels[i], this, ecModel);
            }
            else {
                if (__DEV__) {
                    throw new Error('levels[i].depth is mandatory and should be natural number');
                }
            }
        }
        if (nodes && links) {        // => no return of the data object, when there are links or nodes undefined or null
            const graph = createGraphFromNodeEdge(nodes, links, this, true, beforeLink);
            return graph.data;
        }
        function beforeLink(nodeData: SeriesData, edgeData: SeriesData) {
            nodeData.wrapMethod('getItemModel', function (model: Model, idx: number) {
                const seriesModel = model.parentModel as SankeySeriesModel;
                const layout = seriesModel.getData().getItemLayout(idx);
                if (layout) {
                    const nodeDepth = layout.depth;
                    const levelModel = seriesModel.levelModels[nodeDepth];
                    if (levelModel) {
                        model.parentModel = levelModel;
                    }
                }
                return model;
            });

            edgeData.wrapMethod('getItemModel', function (model: Model, idx: number) {
                const seriesModel = model.parentModel as SankeySeriesModel;
                const edge = seriesModel.getGraph().getEdgeByIndex(idx);
                const layout = edge.node1.getLayout();
                if (layout) {
                    const depth = layout.depth;
                    const levelModel = seriesModel.levelModels[depth];
                    if (levelModel) {
                        model.parentModel = levelModel;
                    }
                }
                return model;
            });
        }
    }

Expected Behavior

There should be no error, because in the interface definition data and links can be undefined.

Environment

- OS: Windows 10
- Browser: Chrome
- Framework: Angular

Any additional comments?

No response

[echarts-bot]

This issue is labeled with difficulty: easy.
@JuNe98 Would you like to debug it by yourself? This is a quicker way to get your problem fixed. Or you may wait for the community to fix.

Please have a look at How to debug ECharts if you'd like to give a try. 🤓

[sz-p]

The way to fix this issue is change interface definition? or if no data just no error no graph?

[JuNe98]

@sz-p yes, I just initially set nodes and links to an empty array and the error is gone. But in the interface it is allowed to set it as undefined or null. So it is a bit confusing.

[sz-p]

@sz-p yes, I just initially set nodes and links to an empty array and the error is gone. But in the interface it is allowed to set it as undefined or null. So it is a bit confusing.

I know what you mean. I just don't know use which way to fix this. need some one more professional to give me some suggestions. I can work on this.

@plainheart can you give me some suggestions?

[plainheart]

The way to fix this issue is change interface definition? or if no data just no error no graph?

@sz-p I agree with the latter way.