fix: reinfer never type in array repeat expressions - #23232
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Array repeat expressions could produce false-positive type mismatches when the initializer diverged and the element type still had to be inferred from later context.
The issue was that
infer_exprcould constrain the fresh inference variable to!too early. I switched this path to the existinginfer_expr_suptype_coerce_neverhelper, which also matches howrustchandles the never-type coercion in this case.I also added a minimal regression test next to the existing never-type reinference tests.
Fixes #23177
Tests:
cargo test -p hir-tycargo clippy -p hir-ty --all-targets -- --cap-lints warncargo lintcargo testAI disclosure: AI was used to help investigate and review the change. I wrote the implementation and ran the validation manually.