From 6ce5ab6a7e566932ad1e3987ae7645eb0125dfe5 Mon Sep 17 00:00:00 2001
From: Vadim Petrochenkov <vadim.petrochenkov@gmail.com>
Date: Wed, 26 Feb 2020 21:24:22 +0300
Subject: [PATCH] rustc_span: Add `Symbol::to_ident_string` for use in
 diagnostic messages

---
 src/librustc_span/symbol.rs | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/librustc_span/symbol.rs b/src/librustc_span/symbol.rs
index b8e5ea97f4e..d6232f32f4c 100644
--- a/src/librustc_span/symbol.rs
+++ b/src/librustc_span/symbol.rs
@@ -1023,6 +1023,14 @@ pub fn as_str(self) -> SymbolStr {
     pub fn as_u32(self) -> u32 {
         self.0.as_u32()
     }
+
+    /// This method is supposed to be used in error messages, so it's expected to be
+    /// identical to printing the original identifier token written in source code
+    /// (`token_to_string`, `Ident::to_string`), except that symbols don't keep the rawness flag
+    /// or edition, so we have to guess the rawness using the global edition.
+    pub fn to_ident_string(self) -> String {
+        Ident::with_dummy_span(self).to_string()
+    }
 }
 
 impl fmt::Debug for Symbol {