fix(states): guard against undefined view in blurSeries

[davesecops]

Brief Information

This pull request is in the type of:

• bug fixing
• new feature
• others

What does this PR do?

Adds a null guard in blurSeries() to prevent a TypeError when api.getViewOfSeriesModel() returns undefined for disposed series during mouse events.

Fixed issues

• [Bug] Cannot read properties of undefined (reading 'group') in blurSeries during React re-render #21559: Cannot read properties of undefined (reading 'group') in blurSeries during React re-render
• Related: Cannot read property 'getRawIndex' of undefined #9402, [Bug] TypeError in getDataParams when getData() returns null on disposed series #21535 (same class of bug — stale series references during mouse events)

Details

Before: What was the problem?

In blurSeries() (src/util/states.ts), api.getViewOfSeriesModel(seriesModel) can return undefined when a series model still exists in GlobalModel but its view has been disposed during a React/Vue re-render cycle (via setOption with notMerge, or component unmount). The code unconditionally accesses view.group:

const view = api.getViewOfSeriesModel(seriesModel);
view.group.traverse(function (child) {  // 💥 TypeError if view is undefined

This is triggered by mousemove events that fire on stale DOM elements during the window between disposal and re-creation. The call path is:

HandlerDomProxy.mousemove → Handler.mousemove → Handler.dispatchToElement →
Eventful.trigger → handleGlobalMouseOverForHighDown → blurSeries →
eachSeries callback → view.group.traverse  💥

After: How does it behave after the fixing?

const view = api.getViewOfSeriesModel(seriesModel);
if (!view || !view.group) {
    return;
}
view.group.traverse(function (child) {

The blur effect is simply skipped for disposed series — consistent with the existing pattern in toggleSeriesBlurState and allLeaveBlur which already handle undefined views gracefully.

Related test cases or examples to use the new APIs

This is a race condition triggered by real user mouse interaction during framework re-renders. The fix is defensive — it prevents a crash on a code path that can legitimately receive undefined, matching patterns already used elsewhere in the same file.

Document Info

• This PR doesn't relate to document changes

Misc

Security Checking

• This PR uses security-sensitive Web APIs.

ZRender Changes

• This PR depends on ZRender changes.

Merging options

• Please squash the commits into a single one when merging.

Other information

This is a 3-line addition (null guard + return + closing brace). It is the same class of bug addressed in #21537 (getDataParams null guard) — both stem from stale series references during mouse events on disposed charts. This PR specifically guards the blurSeries → view.group access path which is not covered by the getDataParams fix.

Author: David Langlands david@grantllama.com
Co-Authored-By: Claude Opus 4.6 noreply@anthropic.com

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