Anonymous closure arguments inside #expect fail in macro expansion

[grynspan]

Description

The following test function fails to compile due to the use of anonymous closure arguments along with the macro expansion generating another closure to contain them:

    @Test func foo() {
        let x = [2, 4, 6]
        x.forEach {
            #expect($0 % 2 == 0)
        }
    }

Errors vary slightly depending on the exact expression and compiler version.

Expected behavior

We should be able to expand this macro correctly by substituting our own labels for dollar identifiers in the initial expression.

Actual behavior

Compiler go splat.

Steps to reproduce

Try to build the test function above.

swift-testing version/commit hash

808e44f

Swift & OS version (output of swift --version ; uname -a)

No response

[grynspan]

Blocked by swiftlang/swift-syntax#2256
Blocked by swiftlang/swift#68475

Tracked internally as rdar://114275884.

[grynspan]

Looks like this was fixed in yesterday's toolchain for us!

[grynspan]

Duplicate of swiftlang/swift#68475