From 57444cf9f31b304d9759b63112f0957315592922 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Fri, 15 Sep 2023 08:21:40 +0200
Subject: use pretty_print_const_value from MIR constant 'extra' printing

---
 compiler/rustc_data_structures/src/lib.rs | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

(limited to 'compiler/rustc_data_structures/src')

diff --git a/compiler/rustc_data_structures/src/lib.rs b/compiler/rustc_data_structures/src/lib.rs
index bee5a89c4c7..7d037ddfa98 100644
--- a/compiler/rustc_data_structures/src/lib.rs
+++ b/compiler/rustc_data_structures/src/lib.rs
@@ -47,6 +47,8 @@ extern crate cfg_if;
 #[macro_use]
 extern crate rustc_macros;
 
+use std::fmt;
+
 pub use rustc_index::static_assert_size;
 
 #[inline(never)]
@@ -126,6 +128,23 @@ impl<F: FnOnce()> Drop for OnDrop<F> {
     }
 }
 
+/// Turns a closure that takes an `&mut Formatter` into something that can be display-formatted.
+pub fn make_display(f: impl Fn(&mut fmt::Formatter<'_>) -> fmt::Result) -> impl fmt::Display {
+    struct Printer<F> {
+        f: F,
+    }
+    impl<F> fmt::Display for Printer<F>
+    where
+        F: Fn(&mut fmt::Formatter<'_>) -> fmt::Result,
+    {
+        fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+            (self.f)(fmt)
+        }
+    }
+
+    Printer { f }
+}
+
 // See comments in src/librustc_middle/lib.rs
 #[doc(hidden)]
 pub fn __noop_fix_for_27438() {}
-- 
cgit 1.4.1-3-g733a5