Overhaul the `intravisit::Map` trait.

First of all, note that `Map` has three different relevant meanings.
- The `intravisit::Map` trait.
- The `map::Map` struct.
- The `NestedFilter::Map` associated type.

The `intravisit::Map` trait is impl'd twice.
- For `!`, where the methods are all unreachable.
- For `map::Map`, which gets HIR stuff from the `TyCtxt`.

As part of getting rid of `map::Map`, this commit changes `impl
intravisit::Map for map::Map` to `impl intravisit::Map for TyCtxt`. It's
fairly straightforward except various things are renamed, because the
existing names would no longer have made sense.

- `trait intravisit::Map` becomes `trait intravisit::HirTyCtxt`, so named
  because it gets some HIR stuff from a `TyCtxt`.
- `NestedFilter::Map` assoc type becomes `NestedFilter::MaybeTyCtxt`,
  because it's always `!` or `TyCtxt`.
- `Visitor::nested_visit_map` becomes `Visitor::maybe_tcx`.

I deliberately made the new trait and associated type names different to
avoid the old `type Map: Map` situation, which I found confusing. We now
have `type MaybeTyCtxt: HirTyCtxt`.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/librustdoc/clean/inline.rs b/src/librustdoc/clean/inline.rs
index 0cdf1b98915..e10a74221ae 100644
--- a/src/librustdoc/clean/inline.rs
+++ b/src/librustdoc/clean/inline.rs
@@ -703,7 +703,7 @@ fn build_module_items(
 pub(crate) fn print_inlined_const(tcx: TyCtxt<'_>, did: DefId) -> String {
     if let Some(did) = did.as_local() {
         let hir_id = tcx.local_def_id_to_hir_id(did);
-        rustc_hir_pretty::id_to_string(&tcx.hir(), hir_id)
+        rustc_hir_pretty::id_to_string(&tcx, hir_id)
     } else {
         tcx.rendered_const(did).clone()
     }