Fix MSSQL decoding large unsigned u32 & u16

Tracking in #14

Author: saltymango2619

sqlx-core/src/mssql/types/int.rs

@@ -172,7 +172,7 @@ fn decode_numeric(bytes: &[u8], _precision: u8, mut scale: u8) -> Result<i64, Bo
     Ok(n * if negative { -1 } else { 1 })
 }
 
-fn convert_integer<T>(i64_val: i64) -> Result<T, BoxDynError>
+pub(super) fn convert_integer<T>(i64_val: i64) -> Result<T, BoxDynError>
 where
     T: TryFrom<i64>,
     T::Error: std::error::Error + Send + Sync + 'static,

sqlx-core/src/mssql/types/uint.rs

@@ -53,8 +53,8 @@ impl Encode<'_, Mssql> for u16 {
 
 impl Decode<'_, Mssql> for u16 {
     fn decode(value: MssqlValueRef<'_>) -> Result<Self, BoxDynError> {
-        let v = <i16 as Decode<'_, Mssql>>::decode(value)?;
-        Ok(u16::try_from(v)?)
+        let i64_val = <i64 as Decode<Mssql>>::decode(value)?;
+        super::int::convert_integer::<Self>(i64_val)
     }
 }
 
@@ -80,8 +80,8 @@ impl Encode<'_, Mssql> for u32 {
 
 impl Decode<'_, Mssql> for u32 {
     fn decode(value: MssqlValueRef<'_>) -> Result<Self, BoxDynError> {
-        let v = <i32 as Decode<'_, Mssql>>::decode(value)?;
-        Ok(u32::try_from(v)?)
+        let i64_val = <i64 as Decode<Mssql>>::decode(value)?;
+        super::int::convert_integer::<Self>(i64_val)
     }
 }