fix: slot binding on inner element read error in arrow function

[magentaqin]

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Tests

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Description

Related #7485
As I commented in this issue, the root reason is not about named slot or default slot. The root reason of the bug is let binding on inner fragment element can not read in arrow function.

[tanhauhau]

Thanks! I've moved the test from parser test, which just test if it can parse the code correctly, to a runtime test, which test if the component works as expected after being compiled without errors, asserting that the innerCall function works as expected

[magentaqin]

@tanhauhau Thanks for adding runtime test! Still, I think runtime and parser test are both necessary, as this bug is at compiler stage and will throw error when running npm run build.

[tanhauhau]

@tanhauhau Thanks for adding runtime test! Still, I think runtime and parser test are both necessary, as this bug is at compiler stage and will throw error when running npm run build.

if the component build could not be build, the runtime test would failed too.

[magentaqin]

@tanhauhau Thanks for adding runtime test! Still, I think runtime and parser test are both necessary, as this bug is at compiler stage and will throw error when running npm run build.

if the component build could not be build, the runtime test would failed too.

Got it.

[magentaqin]

@tanhauhau I notice this PR has been approved but not merged. Is this PR any merging problem?