From 83d7bad54ba5db3a44198d6df0ff2e81621683fa Mon Sep 17 00:00:00 2001
From: David Tolnay <dtolnay@gmail.com>
Date: Fri, 26 Jan 2024 13:14:48 -0800
Subject: [PATCH] Format f64 in error messages using ryu

---
 src/error.rs | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/error.rs b/src/error.rs
index 0e3323972..fbf9eb14e 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -466,10 +466,14 @@ struct JsonUnexpected<'a>(de::Unexpected<'a>);
 
 impl<'a> Display for JsonUnexpected<'a> {
     fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
-        if let de::Unexpected::Unit = self.0 {
-            formatter.write_str("null")
-        } else {
-            Display::fmt(&self.0, formatter)
+        match self.0 {
+            de::Unexpected::Unit => formatter.write_str("null"),
+            de::Unexpected::Float(value) => write!(
+                formatter,
+                "floating point `{}`",
+                ryu::Buffer::new().format(value),
+            ),
+            unexp => Display::fmt(&unexp, formatter),
         }
     }
 }