Use "RFC 2528: type-changing struct update syntax" when it is stabilized

[sezna]

I recently refactored a lot of semantic_analysis to use a struct called TypeCheckArguments. This provides a consistent interface across our many type checking functions.

I wanted to be able to do something like this:

  TypedExpression::type_check(TypeCheckArguments {
      checkee: lhs.clone(),
      help_text: Default::default(),
      mode: Mode::NonAbi, opts,
      ..arguments
  }),

However, this implicit cast of arguments from TypeCheckArguments<T> to TypeCheckArguments<R> is experimental, and nightly only: rust-lang/rust#86555

Without that cast, we have to write this:

    TypedExpression::type_check(TypeCheckArguments {
        checkee: lhs.clone(),
        help_text: Default::default(),
        mode: Mode::NonAbi, opts,
        self_type,
        namespace,
        crate_namespace,
        return_type_annotation,
        build_config,
        dead_code_graph,
        dependency_graph,
    })

This could save us a ton of LOC -- we are currently manually plumbing parameters in lots of places. Once the above issue gets to rust stable, we should refactor these calls to use this syntax.

[sezna]

Along with this issue, we could switch all type checking functions to use t he TypeCheckArguments abstraction

[otrho]

Since most (half? 5/10?) of those args are re-used, would it work to have a type checker struct and just make all the type checks methods? I guess it would be spread across multiple source files, but still fit under the semantic actions type checking umbrella.

[sezna]

Some of them are truly never modified, like the dead code graph and stuff. That's a good idea!

[mohammadfawaz]

#2004 switched all instances of TypeCheckArguments to use a context instead. I believe this can be closed now.