Rollup merge of #144776 - nnethercote:Printer-cleanups, r=cjgillot

`Printer` cleanups

The trait `Printer` is implemented by six types, and the sub-trait `PrettyPrinter` is implemented by three of those types. The traits and the impls are complex and a bit of a mess. This PR starts to clean them up.

r? ``@davidtwco``

1 files changed, 7 insertions, 6 deletions

diff --git a/compiler/rustc_const_eval/src/interpret/operand.rs b/compiler/rustc_const_eval/src/interpret/operand.rs
index 41713457908..14541809070 100644
--- a/compiler/rustc_const_eval/src/interpret/operand.rs
+++ b/compiler/rustc_const_eval/src/interpret/operand.rs
@@ -188,18 +188,18 @@ pub struct ImmTy<'tcx, Prov: Provenance = CtfeProvenance> {
 impl<Prov: Provenance> std::fmt::Display for ImmTy<'_, Prov> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         /// Helper function for printing a scalar to a FmtPrinter
-        fn p<'a, 'tcx, Prov: Provenance>(
-            cx: &mut FmtPrinter<'a, 'tcx>,
+        fn print_scalar<'a, 'tcx, Prov: Provenance>(
+            p: &mut FmtPrinter<'a, 'tcx>,
             s: Scalar<Prov>,
             ty: Ty<'tcx>,
         ) -> Result<(), std::fmt::Error> {
             match s {
-                Scalar::Int(int) => cx.pretty_print_const_scalar_int(int, ty, true),
+                Scalar::Int(int) => p.pretty_print_const_scalar_int(int, ty, true),
                 Scalar::Ptr(ptr, _sz) => {
                     // Just print the ptr value. `pretty_print_const_scalar_ptr` would also try to
                     // print what is points to, which would fail since it has no access to the local
                     // memory.
-                    cx.pretty_print_const_pointer(ptr, ty)
+                    p.pretty_print_const_pointer(ptr, ty)
                 }
             }
         }
@@ -207,8 +207,9 @@ impl<Prov: Provenance> std::fmt::Display for ImmTy<'_, Prov> {
             match self.imm {
                 Immediate::Scalar(s) => {
                     if let Some(ty) = tcx.lift(self.layout.ty) {
-                        let s =
-                            FmtPrinter::print_string(tcx, Namespace::ValueNS, |cx| p(cx, s, ty))?;
+                        let s = FmtPrinter::print_string(tcx, Namespace::ValueNS, |p| {
+                            print_scalar(p, s, ty)
+                        })?;
                         f.write_str(&s)?;
                         return Ok(());
                     }