Make single_range_in_vec_init ignore type annotations, fn arguments and ExprFields

[matzemathics]

picking up on #11088.

I will still look at using #11166, as @Alexendoo suggested there.

changelog: Enhancement: [single_range_in_vec_init]: Ignores if it's a local that has type annotations, or is immediately passed to a function or struct initializer

[rustbot]

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[dswij]

Just a friendly ping to check in on the progress and if you need any help to move it forward @matzemathics :)

[matzemathics]

@dswij I got (still am) somewhat confused, because the suggested lib::expr_use_ctxt did not manage to find the parents: It returns an ExprUseCtxt { ExprUseNode::Other, ... } if the expression is unused (used as a statement), which is expected. But in all other cases I just got None. I suspect the following check is wrong, and should check the span of child_id instead of parent_id, but then again, that would affect other lints, so why does it work elsewhere?

rust-clippy/clippy_utils/src/lib.rs

Lines 2754 to 2756 in 7063e34

	if cx.tcx.hir().span(parent_id).ctxt() != ctxt {
	return ControlFlow::Break(());
	}

So if you have any ideas, help would be much appreciated.

EDIT: I tried changing the check in question, and all uitests still pass, so maybe this is a logic error in the expr_use_ctxt function?