Support 128-bit integers in to_value

Author: dtolnay

src/value/ser.rs

@@ -5,6 +5,8 @@ use crate::value::{to_value, Value};
 use alloc::borrow::ToOwned;
 use alloc::string::{String, ToString};
 use alloc::vec::Vec;
+#[cfg(not(feature = "arbitrary_precision"))]
+use core::convert::TryFrom;
 use core::fmt::Display;
 use core::result;
 use serde::ser::{Impossible, Serialize};
@@ -92,9 +94,22 @@ impl serde::Serializer for Serializer {
         Ok(Value::Number(value.into()))
     }
 
-    #[cfg(feature = "arbitrary_precision")]
     fn serialize_i128(self, value: i128) -> Result<Value> {
-        Ok(Value::Number(value.into()))
+        #[cfg(feature = "arbitrary_precision")]
+        {
+            Ok(Value::Number(value.into()))
+        }
+
+        #[cfg(not(feature = "arbitrary_precision"))]
+        {
+            if let Ok(value) = u64::try_from(value) {
+                Ok(Value::Number(value.into()))
+            } else if let Ok(value) = i64::try_from(value) {
+                Ok(Value::Number(value.into()))
+            } else {
+                Err(Error::syntax(ErrorCode::NumberOutOfRange, 0, 0))
+            }
+        }
     }
 
     #[inline]
@@ -117,9 +132,20 @@ impl serde::Serializer for Serializer {
         Ok(Value::Number(value.into()))
     }
 
-    #[cfg(feature = "arbitrary_precision")]
     fn serialize_u128(self, value: u128) -> Result<Value> {
-        Ok(Value::Number(value.into()))
+        #[cfg(feature = "arbitrary_precision")]
+        {
+            Ok(Value::Number(value.into()))
+        }
+
+        #[cfg(not(feature = "arbitrary_precision"))]
+        {
+            if let Ok(value) = u64::try_from(value) {
+                Ok(Value::Number(value.into()))
+            } else {
+                Err(Error::syntax(ErrorCode::NumberOutOfRange, 0, 0))
+            }
+        }
     }
 
     #[inline]