[Bug] Stacked bar regression when changing from 5.2.2 to 5.3.0

[dirslashls]

Version

5.3.0

Link to Minimal Reproduction

No response

Steps to Reproduce

Use the following code and notice that in 5.2.2 the bars stack up while in 5.3.0 they seem to be one on top of the other essentially showing only one bar.

Go to https://echarts.apache.org/examples/en/editor.html and try the following in 5.2.2 and 5.3.0.

option = {
    "xAxis": [
        {
            "gridIndex": 0,
            "type": "category"
        }
    ],
    "yAxis": [
        {
            "gridIndex": 0,
            "type": "value"
        }
    ],
    "visualMap": [
        {
            "type": "piecewise",
            "dimension": "Sales Channel",
            "categories": [
                "Offline",
                "Online"
            ],
            "seriesIndex": [
                0
            ],
            "orient": "horizontal",
            "top": 30,
            "left": 90
        }
    ],
    "series": [
        {
            "type": "bar",
            "name": "",
            "label": {
                "show": false
            },
            "stack": "stack_0.0.0.0_y_0",
            "coordinateSystem": "cartesian2d",
            "xAxisIndex": 0,
            "yAxisIndex": 0,
            "encode": {
                "x": 1,
                "y": 2,
            },
            "emphasis": {
                "itemStyle": {
                    "shadowBlur": 3
                }
            },
            "sampling": "lttb",
            "barMaxWidth": 100,
            "dimensions": [
                {
                    "name": "Sales Channel"
                },
                {
                    "name": "Region"
                },
                {
                    "name": "Revenue",
                    "type": "float"
                }
            ],
            "data": [
                {
                    "value": [
                        "Offline",
                        "Asia",
                        940911478.85
                    ]
                },
                {
                    "value": [
                        "Online",
                        "Asia",
                        1064394097.17
                    ]
                },
            ],
            "id": "series_0"
        }
    ]
}

Current Behavior

The bar chart has 2 data points for the same x-axis category value of Asia. However, there is a piecewise visualmap on a different category dimension. In 5.2.2 this results in showing the data as stacked with the "stack" option. But in 5.3.0 one data point seem to overwrite the other.

Expected Behavior

The bar should show as stacked.

Environment

- OS: N/A
- Browser: N/A
- Framework: N/A

Any additional comments?

The stacking behavior as seen in 5.2.2 was there for a long time including in v4.

[pissang]

@dirslashls The stack should be not applied in one series. Stack will only be applied between two series. The original behavior is not expected.

[dirslashls]

@pissang, thanks for providing the reason for why this is now happening. The requirement to have separate series for stacked bar works well for static stacks (like cost + profit = total revenue), but forces to create lots of series if the stack is dynamic (revenue broken down by country). It would be nice to not regress the existing behavior if possible or provide any other suitable way to solve the dynamic stacks without creating one series per dimension value.