Move literal_to_string to fmt::Display

2 files changed, 29 insertions, 1 deletions

diff --git a/src/libsyntax/parse/literal.rs b/src/libsyntax/parse/literal.rs
index ef55bf6b929..683d1641565 100644
--- a/src/libsyntax/parse/literal.rs
+++ b/src/libsyntax/parse/literal.rs
@@ -344,7 +344,7 @@ impl<'a> Parser<'a> {
                 // Pack possible quotes and prefixes from the original literal into
                 // the error literal's symbol so they can be pretty-printed faithfully.
                 let suffixless_lit = token::Lit::new(lit.kind, lit.symbol, None);
-                let symbol = Symbol::intern(&pprust::literal_to_string(suffixless_lit));
+                let symbol = Symbol::intern(&suffixless_lit.to_string());
                 let lit = token::Lit::new(token::Err, symbol, lit.suffix);
                 Lit::from_lit_token(lit, span).map_err(|_| unreachable!())
             }
diff --git a/src/libsyntax/parse/token.rs b/src/libsyntax/parse/token.rs
index ebd0decacb5..fccb556b95a 100644
--- a/src/libsyntax/parse/token.rs
+++ b/src/libsyntax/parse/token.rs
@@ -80,6 +80,34 @@ pub struct Lit {
     pub suffix: Option<Symbol>,
 }
 
+impl fmt::Display for Lit {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let Lit { kind, symbol, suffix } = *self;
+        match kind {
+            Byte          => write!(f, "b'{}'", symbol)?,
+            Char          => write!(f, "'{}'", symbol)?,
+            Str           => write!(f, "\"{}\"", symbol)?,
+            StrRaw(n)     => write!(f, "r{delim}\"{string}\"{delim}",
+                                     delim="#".repeat(n as usize),
+                                     string=symbol)?,
+            ByteStr       => write!(f, "b\"{}\"", symbol)?,
+            ByteStrRaw(n) => write!(f, "br{delim}\"{string}\"{delim}",
+                                     delim="#".repeat(n as usize),
+                                     string=symbol)?,
+            Integer       |
+            Float         |
+            Bool          |
+            Err           => write!(f, "{}", symbol)?,
+        }
+
+        if let Some(suffix) = suffix {
+            write!(f, "{}", suffix)?;
+        }
+
+        Ok(())
+    }
+}
+
 impl LitKind {
     /// An English article for the literal token kind.
     crate fn article(self) -> &'static str {