Implement TestSerializer to replace serde_json for the serialize tests

Author: FSMaxB

ext_tests/Cargo.toml

@@ -6,12 +6,11 @@ edition = "2018"
 publish = false
 
 [dependencies]
-serde_json = "1.0"
 serde = "1.0"
 
 [dependencies.js_int]
 path = "../"
 features = ["serde"]
 
 [features]
-lax_deserialize = ["js_int/lax_deserialize", "serde_json/float_roundtrip"]
+lax_deserialize = ["js_int/lax_deserialize"]

ext_tests/src/lib.rs

@@ -1,15 +1,17 @@
+mod test_serializer;
+
 #[cfg(test)]
 mod tests {
-    use serde::{de::IntoDeserializer, Deserialize};
-    use serde_json::{from_str as from_json_str, to_string as to_json_string};
-
     use js_int::{int, uint, Int, UInt};
+    use serde::{de::IntoDeserializer, Deserialize, Serialize};
+
+    use crate::test_serializer::{Serialized, TestSerializer};
 
     #[test]
     fn serialize_int() {
-        assert_eq!(to_json_string(&int!(100)).unwrap(), "100");
-        assert_eq!(to_json_string(&int!(0)).unwrap(), "0");
-        assert_eq!(to_json_string(&int!(-100)).unwrap(), "-100");
+        assert_eq!(int!(100).serialize(TestSerializer).unwrap(), Serialized::Signed(100));
+        assert_eq!(int!(0).serialize(TestSerializer).unwrap(), Serialized::Signed(0));
+        assert_eq!(int!(-100).serialize(TestSerializer).unwrap(), Serialized::Signed(-100));
     }
 
     #[test]
@@ -25,8 +27,8 @@ mod tests {
 
     #[test]
     fn serialize_uint() {
-        assert_eq!(to_json_string(&uint!(100)).unwrap(), "100");
-        assert_eq!(to_json_string(&uint!(0)).unwrap(), "0");
+        assert_eq!(uint!(100).serialize(TestSerializer).unwrap(), Serialized::Unsigned(100));
+        assert_eq!(uint!(0).serialize(TestSerializer).unwrap(), Serialized::Unsigned(0));
     }
 
     #[test]

ext_tests/src/test_serializer.rs

@@ -0,0 +1,181 @@
+use serde::{ser::Impossible, Serialize, Serializer};
+
+pub struct TestSerializer;
+
+#[derive(Debug, PartialEq)]
+pub enum Serialized {
+    Signed(i64),
+    Unsigned(u64),
+}
+
+impl Serializer for TestSerializer {
+    type Ok = Serialized;
+    type Error = serde::de::value::Error;
+    type SerializeSeq = Impossible<Self::Ok, Self::Error>;
+    type SerializeTuple = Impossible<Self::Ok, Self::Error>;
+    type SerializeTupleStruct = Impossible<Self::Ok, Self::Error>;
+    type SerializeTupleVariant = Impossible<Self::Ok, Self::Error>;
+    type SerializeMap = Impossible<Self::Ok, Self::Error>;
+    type SerializeStruct = Impossible<Self::Ok, Self::Error>;
+    type SerializeStructVariant = Impossible<Self::Ok, Self::Error>;
+
+    fn serialize_i64(self, value: i64) -> Result<Self::Ok, Self::Error> {
+        Ok(Serialized::Signed(value))
+    }
+
+    fn serialize_u64(self, value: u64) -> Result<Self::Ok, Self::Error> {
+        Ok(Serialized::Unsigned(value))
+    }
+
+    // Required because `Int` and `UInt` are both newtype structs so this method is called by the
+    // serialize implementation generated by `#[derive(Serialize)]`
+    fn serialize_newtype_struct<T: ?Sized>(
+        self,
+        _: &'static str,
+        value: &T,
+    ) -> Result<Self::Ok, Self::Error>
+    where
+        T: Serialize,
+    {
+        value.serialize(self)
+    }
+
+    // The remaining methods are all unimplemented
+
+    fn serialize_bool(self, _: bool) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_i8(self, _: i8) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_i16(self, _: i16) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_i32(self, _: i32) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_u8(self, _: u8) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_u16(self, _: u16) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_u32(self, _: u32) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_f32(self, _: f32) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_f64(self, _: f64) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_char(self, _: char) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_str(self, _: &str) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_bytes(self, _: &[u8]) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_none(self) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_some<T: ?Sized>(self, _: &T) -> Result<Self::Ok, Self::Error>
+    where
+        T: Serialize,
+    {
+        unimplemented!()
+    }
+
+    fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_unit_struct(self, _: &'static str) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_unit_variant(
+        self,
+        _: &'static str,
+        _: u32,
+        _: &'static str,
+    ) -> Result<Self::Ok, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_newtype_variant<T: ?Sized>(
+        self,
+        _: &'static str,
+        _: u32,
+        _: &'static str,
+        _: &T,
+    ) -> Result<Self::Ok, Self::Error>
+    where
+        T: Serialize,
+    {
+        unimplemented!()
+    }
+
+    fn serialize_seq(self, _: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_tuple(self, _: usize) -> Result<Self::SerializeTuple, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_tuple_struct(
+        self,
+        _: &'static str,
+        _: usize,
+    ) -> Result<Self::SerializeTupleStruct, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_tuple_variant(
+        self,
+        _: &'static str,
+        _: u32,
+        _: &'static str,
+        _: usize,
+    ) -> Result<Self::SerializeTupleVariant, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_map(self, _: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_struct(
+        self,
+        _: &'static str,
+        _: usize,
+    ) -> Result<Self::SerializeStruct, Self::Error> {
+        unimplemented!()
+    }
+
+    fn serialize_struct_variant(
+        self,
+        _: &'static str,
+        _: u32,
+        _: &'static str,
+        _: usize,
+    ) -> Result<Self::SerializeStructVariant, Self::Error> {
+        unimplemented!()
+    }
+}