Generate an plan base on the output

[nevermore3]

What type of PR is this?

• bug
• feature
• enhancement

What problem(s) does this PR solve?

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• Unit test(positive and negative cases)
• Function test
• Performance test
• N/A

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• Performance impacted: Consumes more CPU/Memory

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ex. Fixed the bug .....

[czpmango]

Just return false if you dont care this scenario.

[czpmango]

This is code logic you should check elsewhere than here, IMHO.

[nevermore3]

should report error if user input
go from ... yield vertex as v

[czpmango]

Didn't the previous implementation check that, I mean you shouldn't mess with the logic of checking if there is an endpoint.

[nevermore3]

I think checking whether there is information about the destination vertex and whether to joinDst is logically consistent and does not need to be implemented separately

[nevermore3]

got what's u mean

[czpmango]

Maybe this is better:

bool ExpressionUtils::existAnyDstVertex(const Expression* expr) {
    auto finder = [](const Expression* e) -> bool {
        return (e->kind() == ExprKind::kDstProperty) ||
               (e->kind == ExprKind::kVertex &&
                static_cast<const VertexExpression*>(e)->name() == "$$");
    }
    FindVisitor visitor(finder);
    const_cast<Expression*>(expr)->accept(&visitor);
    return !visitor.results().empty();
}

[czpmango]

goCtx_->joinDst = ExpressionUtils::existAnyDstVertex(filter);

[nevermore3]

although the functions are separated, it also causes repeated verification