Fix #12592: Execution is interrupted when the subsequent flow of the else branch is in a new parallel stream.

[liuzhenghua]

Summary

Fixes #12592

Screenshots

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Checklist

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• This change requires a documentation update, included: Dify Document
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[crazywoola]

Why do you want let if/else execute the same logic? It doesn't make sense to me.

[liuzhenghua]

Why do you want let if/else execute the same logic? It doesn't make sense to me.

They do not execute the same logic. The if branch executes a parallel stream, while the else branch only executes a single line of the if branch's parallel stream.

The demo provided is only to demonstrate this bug. Our actual business logic is as shown in the figure below.

When the condition leads to the else branch, it gets interrupted and does not execute the else node as expected.

[crazywoola]

But it looks like the if/else are executing the same logic, this is confused by the UI. I don't think the if/else node should support parallel executing if they are using the same condition.