Add support for json deserializing enums and options, clean up tests

json.rs

@@ -316,9 +316,10 @@ enum JsonDeserializerState {
     JsonDeserializerValueState(Json),
     JsonDeserializerListState(vec::MoveItems<Json>),
     JsonDeserializerObjectState(treemap::MoveEntries<String, Json>),
+    JsonDeserializerEndState,
 }
 
-struct JsonDeserializer {
+pub struct JsonDeserializer {
     stack: Vec<JsonDeserializerState>,
 }
 
@@ -380,6 +381,9 @@ impl Iterator<Result<de::Token, ParserError>> for JsonDeserializer {
                         }
                     }
                 }
+                Some(JsonDeserializerEndState) => {
+                    return Some(Ok(de::End));
+                }
                 None => { return None; }
             }
         }
@@ -394,6 +398,131 @@ impl de::Deserializer<ParserError> for JsonDeserializer {
     fn syntax_error(&self) -> ParserError {
         SyntaxError(InvalidSyntax, 0, 0)
     }
+
+    // Special case treating options as a nullable value.
+    #[inline]
+    fn expect_option<
+        U: de::Deserializable<ParserError, JsonDeserializer>
+    >(&mut self, token: de::Token) -> Result<Option<U>, ParserError> {
+        match token {
+            de::Null => Ok(None),
+            token => {
+                let value: U = try!(de::Deserializable::deserialize_token(self, token));
+                Ok(Some(value))
+            }
+        }
+    }
+
+    #[inline]
+    fn expect_enum_start(&mut self, token: de::Token, _name: &str, variants: &[&str]) -> Result<uint, ParserError> {
+        let variant = match token {
+            de::String(variant) => {
+                self.stack.push(JsonDeserializerEndState);
+                variant
+            }
+            de::MapStart(_) => {
+                let state = match self.stack.pop() {
+                    Some(state) => state,
+                    None => { fail!("state machine error, state stack empty"); }
+                };
+
+                let mut iter = match state {
+                    JsonDeserializerObjectState(iter) => iter,
+                    _ => { fail!("state machine error, expected an object"); }
+                };
+
+                let mut variant = None;
+                let mut fields = None;
+
+                for (key, value) in iter {
+                    if key.equiv(&"variant") {
+                        match value {
+                            String(v) => { variant = Some(v); }
+                            value => {
+                                return Err(ExpectedError("String".to_string(),
+                                                         format!("{}", value)))
+                            }
+                        }
+                    } else if key.equiv(&"fields") {
+                        match value {
+                            List(v) => { fields = Some(v); }
+                            value => {
+                                return Err(ExpectedError("List".to_string(),
+                                                         format!("{}", value)))
+                            }
+                        }
+                    }
+                }
+
+                let (variant, fields) = match (variant, fields) {
+                    (Some(variant), Some(fields)) => (variant, fields),
+                    (None, _) => {
+                        return Err(MissingFieldError("variant".to_string()))
+                    }
+                    (_, None) => {
+                        return Err(MissingFieldError("fields".to_string()))
+                    }
+                };
+
+                self.stack.push(JsonDeserializerEndState);
+
+                for field in fields.move_iter().rev() {
+                    self.stack.push(JsonDeserializerValueState(field));
+                }
+
+                variant
+            }
+            token => {
+                return Err(ExpectedError("String or Object".to_string(),
+                                         format!("{}", token)))
+            }
+        };
+
+
+        /*
+
+
+        let name = match self.stack.pop() {
+            String(s) => s,
+            Object(mut object) => {
+                let n = match object.pop_equiv(&"variant") {
+                    Some(String(s)) => s,
+                    Some(value) => {
+                        return Err(ExpectedError("String".to_string(),
+                                                 format!("{}", value)))
+                    }
+                    None => {
+                        return Err(MissingFieldError("variant".to_string()))
+                    }
+                };
+                match object.pop_equiv(&"fields") {
+                    Some(List(list)) => {
+                        for field in list.move_iter().rev() {
+                            self.stack.push(JsonDeserializerValueState(field));
+                        }
+                    },
+                    Some(value) => {
+                        return Err(ExpectedError("List".to_string(),
+                                                 format!("{}", value)))
+                    }
+                    None => {
+                        return Err(MissingFieldError("fields".to_string()))
+                    }
+                }
+                n
+            }
+            json => {
+                return Err(ExpectedError("String or Object".to_string(),
+                                         format!("{}", json)))
+            }
+        };
+        */
+
+        match variants.iter().position(|v| *v == variant.as_slice()) {
+            Some(idx) => Ok(idx),
+            None => Err(UnknownVariantError(variant)),
+        }
+    }
 }
 
 /// The errors that can arise while parsing a JSON stream.
@@ -422,11 +551,15 @@ pub enum ParserError {
     /// msg, line, col
     SyntaxError(ErrorCode, uint, uint),
     IoError(io::IoErrorKind, &'static str),
+    ExpectedError(String, String),
+    MissingFieldError(String),
+    UnknownVariantError(String),
 }
 
 // Builder and Parser have the same errors.
 pub type BuilderError = ParserError;
 
+/*
 #[deriving(Clone, Eq, Show)]
 pub enum DecoderError {
     ParseError(ParserError),
@@ -434,6 +567,7 @@ pub enum DecoderError {
     MissingFieldError(String),
     UnknownVariantError(String),
 }
+*/
 
 /// Returns a readable error string for a given error code.
 pub fn error_str(error: ErrorCode) -> &'static str {
@@ -469,7 +603,7 @@ fn io_error_to_error(io: io::IoError) -> ParserError {
 }
 
 pub type EncodeResult = io::IoResult<()>;
-pub type DecodeResult<T> = Result<T, DecoderError>;
+//pub type DecodeResult<T> = Result<T, DecoderError>;
 
 fn escape_str(s: &str) -> String {
     let mut escaped = String::from_str("\"");
@@ -1754,7 +1888,7 @@ impl<T: Iterator<char>> de::Deserializer<ParserError> for Parser<T> {
     #[inline]
     fn expect_enum_start(&mut self, token: de::Token, _name: &str, variants: &[&str]) -> Result<uint, ParserError> {
         match token {
-            Str(name) => 
+            Str(name) =>
 
         }
 
@@ -2463,7 +2597,7 @@ mod tests {
         Object,
     };
     use super::{Parser, ParserError, from_iter};
-    use super::{JsonDeserializer, from_json};
+    use super::{JsonDeserializer, from_json, ToJson};
     use super::{
         EOFWhileParsingList,
         EOFWhileParsingObject,
@@ -2472,7 +2606,7 @@ mod tests {
         ExpectedColon,
         InvalidNumber,
         InvalidSyntax,
-        KeyMustBeAString, 
+        KeyMustBeAString,
         TrailingCharacters,
         SyntaxError,
     };
@@ -2483,6 +2617,14 @@ mod tests {
     use std::str;
     use collections::TreeMap;
 
+    macro_rules! treemap {
+        ($($k:expr => $v:expr),*) => ({
+            let mut _m = ::collections::TreeMap::new();
+            $(_m.insert($k, $v);)*
+            _m
+        })
+    }
+
     #[deriving(Eq, Show)]
     enum Animal {
         Dog,
@@ -2574,6 +2716,18 @@ mod tests {
         }
     }
 
+    impl ToJson for Inner {
+        fn to_json(&self) -> Json {
+            Object(
+                treemap!(
+                    "a".to_string() => self.a.to_json(),
+                    "b".to_string() => self.b.to_json(),
+                    "c".to_string() => self.c.to_json()
+                )
+            )
+        }
+    }
+
     #[deriving(Eq, Show)]
     struct Outer {
         inner: Vec<Inner>,
@@ -2622,6 +2776,16 @@ mod tests {
         }
     }
 
+    impl ToJson for Outer {
+        fn to_json(&self) -> Json {
+            Object(
+                treemap!(
+                    "inner".to_string() => self.inner.to_json()
+                )
+            )
+        }
+    }
+
     /*
     fn mk_object(items: &[(String, Json)]) -> Json {
         let mut d = box TreeMap::new();
@@ -2874,59 +3038,61 @@ mod tests {
     }
     */
 
-    fn test_parser_err<
+    fn test_parse_err<
         'a,
         T: Eq + Show + de::Deserializable<ParserError, Parser<str::Chars<'a>>>
     >(errors: &[(&'a str, ParserError)]) {
-        for &(s, err) in errors.iter() {
+        for &(s, ref err) in errors.iter() {
             let v: Result<T, ParserError> = from_iter(s.chars());
-            assert_eq!(v, Err(err));
+            assert_eq!(v.unwrap_err(), *err);
         }
     }
 
-    fn test_parser_ok<
+    fn test_parse_ok<
         'a,
-        T: Eq + Show + de::Deserializable<ParserError, Parser<str::Chars<'a>>>
+        T: Eq + Show + ToJson + de::Deserializable<ParserError, Parser<str::Chars<'a>>>
     >(errors: &[(&'a str, T)]) {
         for &(s, ref value) in errors.iter() {
             let v: T = from_iter(s.chars()).unwrap();
             assert_eq!(v, *value);
+
+            let v: Json = from_iter(s.chars()).unwrap();
+            assert_eq!(v, value.to_json());
         }
     }
 
-    fn test_json_deserializer_ok<
-        T: Eq + Show + de::Deserializable<ParserError, JsonDeserializer>
-    >(errors: &[(Json, T)]) {
-        for &(ref json, ref value) in errors.iter() {
-            let v: T = from_json(json.clone()).unwrap();
+    fn test_json_deserialize_ok<
+        T: Eq + Show + ToJson + de::Deserializable<ParserError, JsonDeserializer>
+    >(errors: &[T]) {
+        for value in errors.iter() {
+            let v: T = from_json(value.to_json()).unwrap();
             assert_eq!(v, *value);
         }
     }
 
     #[test]
-    fn test_decode_null() {
-        test_parser_err::<()>([
+    fn test_parse_null() {
+        test_parse_err::<()>([
             ("n", SyntaxError(InvalidSyntax, 1, 2)),
             ("nul", SyntaxError(InvalidSyntax, 1, 4)),
             ("nulla", SyntaxError(TrailingCharacters, 1, 5)),
         ]);
 
-        test_parser_ok([
+        test_parse_ok([
             ("null", ()),
         ]);
-
-        test_parser_ok([
-            ("null", Null),
-        ]);
-
-        test_json_deserializer_ok([
-            (Null, ()),
-        ]);
     }
 
     #[test]
-    fn test_decode_bool() {
-        test_parser_err::<bool>([
+    fn test_json_deserialize_null() {
+        test_json_deserialize_ok([
+            (),
+        ]);
+    }
+
+    #[test]
+    fn test_parse_bool() {
+        test_parse_err::<bool>([
             ("t", SyntaxError(InvalidSyntax, 1, 2)),
             ("truz", SyntaxError(InvalidSyntax, 1, 4)),
             ("f", SyntaxError(InvalidSyntax, 1, 2)),
@@ -2935,20 +3101,17 @@ mod tests {
             ("falsea", SyntaxError(TrailingCharacters, 1, 6)),
         ]);
 
-        test_parser_ok([
+        test_parse_ok([
             ("true", true),
             ("false", false),
         ]);
+    }
 
-        test_parser_ok([
-            ("true", Boolean(true)),
-            ("false", Boolean(false)),
-        ]);
-
-
-        test_json_deserializer_ok([
-            (Boolean(true), true),
-            (Boolean(false), false),
+    #[test]
+    fn test_json_deserialize_bool() {
+        test_json_deserialize_ok([
+            true,
+            false,
         ]);
     }
 
@@ -2975,8 +3138,8 @@ mod tests {
     */
 
     #[test]
-    fn test_decode_numbers() {
-        let errors = [
+    fn test_parse_numbers() {
+        test_parse_err::<f64>([
             ("+", SyntaxError(InvalidSyntax, 1, 1)),
             (".", SyntaxError(InvalidSyntax, 1, 1)),
             ("-", SyntaxError(InvalidNumber, 1, 2)),
@@ -2985,14 +3148,9 @@ mod tests {
             ("1e", SyntaxError(InvalidNumber, 1, 3)),
             ("1e+", SyntaxError(InvalidNumber, 1, 4)),
             ("1a", SyntaxError(TrailingCharacters, 1, 2)),
-        ];
+        ]);
 
-        for &(s, err) in errors.iter() {
-            let v: Result<f64, ParserError> = from_iter(s.chars());
-            assert_eq!(v, Err(err));
-        }
-
-        let values = [
+        test_parse_ok([
             ("3", 3.0),
             ("3.1", 3.1),
             ("-1.2", -1.2),
@@ -3000,12 +3158,20 @@ mod tests {
             ("0.4e5", 0.4e5),
             ("0.4e15", 0.4e15),
             ("0.4e-01", 0.4e-01),
-        ];
+        ]);
+    }
 
-        for &(s, value) in values.iter() {
-            let v: Result<f64, ParserError> = from_iter(s.chars());
-            assert_eq!(v, Ok(value));
-        }
+    #[test]
+    fn test_json_deserialize_numbers() {
+        test_json_deserialize_ok([
+            3.0,
+            3.1,
+            -1.2,
+            0.4,
+            0.4e5,
+            0.4e15,
+            0.4e-01,
+        ]);
     }
 
     /*
@@ -3028,33 +3194,39 @@ mod tests {
     */
 
     #[test]
-    fn test_decode_str() {
-        let errors = [
+    fn test_parse_str() {
+        test_parse_err::<String>([
             ("\"", SyntaxError(EOFWhileParsingString, 1, 2)),
             ("\"lol", SyntaxError(EOFWhileParsingString, 1, 5)),
             ("\"lol\"a", SyntaxError(TrailingCharacters, 1, 6)),
-        ];
+        ]);
 
-        for &(s, err) in errors.iter() {
-            let v: Result<String, ParserError> = from_iter(s.chars());
-            assert_eq!(v, Err(err));
-        }
+        test_parse_ok([
+            ("\"\"", "".to_string()),
+            ("\"foo\"", "foo".to_string()),
+            ("\"\\\"\"", "\"".to_string()),
+            ("\"\\b\"", "\x08".to_string()),
+            ("\"\\n\"", "\n".to_string()),
+            ("\"\\r\"", "\r".to_string()),
+            ("\"\\t\"", "\t".to_string()),
+            ("\"\\u12ab\"", "\u12ab".to_string()),
+            ("\"\\uAB12\"", "\uAB12".to_string()),
+        ]);
+    }
 
-        let s = [("\"\"", ""),
-                 ("\"foo\"", "foo"),
-                 ("\"\\\"\"", "\""),
-                 ("\"\\b\"", "\x08"),
-                 ("\"\\n\"", "\n"),
-                 ("\"\\r\"", "\r"),
-                 ("\"\\t\"", "\t"),
-                 ("\"\\u12ab\"", "\u12ab"),
-                 ("\"\\uAB12\"", "\uAB12")];
-
-        for &(i, o) in s.iter() {
-            let mut parser = Parser::new(i.chars());
-            let v: String = de::Deserializable::deserialize(&mut parser).unwrap();
-            assert_eq!(v.as_slice(), o);
-        }
+    #[test]
+    fn test_json_deserialize_str() {
+        test_json_deserialize_ok([
+            "".to_string(),
+            "foo".to_string(),
+            "\"".to_string(),
+            "\x08".to_string(),
+            "\n".to_string(),
+            "\r".to_string(),
+            "\t".to_string(),
+            "\u12ab".to_string(),
+            "\uAB12".to_string(),
+        ]);
     }
 
     /*
@@ -3081,44 +3253,56 @@ mod tests {
     */
 
     #[test]
-    fn test_decode_list() {
-        let errors = [
-            ("[",     SyntaxError(EOFWhileParsingValue, 1, 2)),
-            ("[ ",    SyntaxError(EOFWhileParsingValue, 1, 3)),
-            ("[1",    SyntaxError(EOFWhileParsingList,  1, 3)),
-            ("[1,",   SyntaxError(EOFWhileParsingValue, 1, 4)),
-            ("[1,]",  SyntaxError(InvalidSyntax,        1, 4)),
-            ("[1 2]", SyntaxError(InvalidSyntax,        1, 4)),
+    fn test_parse_list() {
+        test_parse_err::<Vec<f64>>([
+            ("[", SyntaxError(EOFWhileParsingValue, 1, 2)),
+            ("[ ", SyntaxError(EOFWhileParsingValue, 1, 3)),
+            ("[1", SyntaxError(EOFWhileParsingList,  1, 3)),
+            ("[1,", SyntaxError(EOFWhileParsingValue, 1, 4)),
+            ("[1,]", SyntaxError(InvalidSyntax, 1, 4)),
+            ("[1 2]", SyntaxError(InvalidSyntax, 1, 4)),
             ("[]a", SyntaxError(TrailingCharacters, 1, 3)),
-        ];
-        for &(s, err) in errors.iter() {
-            let v: Result<Vec<f64>, ParserError> = from_iter(s.chars());
-            assert_eq!(v, Err(err));
-        }
+        ]);
 
-        let v: Vec<()> = from_iter("[]".chars()).unwrap();
-        assert_eq!(v, vec![]);
+        test_parse_ok([
+            ("[]", vec!()),
+            ("[ ]", vec!()),
+            ("[null]", vec!(())),
+            ("[ null ]", vec!(())),
+        ]);
 
-        let v: Vec<()> = from_iter("[ ]".chars()).unwrap();
-        assert_eq!(v, vec![]);
+        test_parse_ok([
+            ("[true]", vec!(true)),
+        ]);
 
-        let v: Vec<()> = from_iter("[null]".chars()).unwrap();
-        assert_eq!(v, vec![()]);
+        test_parse_ok([
+            ("[3,1]", vec!(3, 1)),
+            ("[ 3 , 1 ]", vec!(3, 1)),
+        ]);
 
-        let v: Vec<()> = from_iter("[ null ]".chars()).unwrap();
-        assert_eq!(v, vec![()]);
+        test_parse_ok([
+            ("[[3], [1, 2]]", vec!(vec!(3), vec!(1, 2))),
+        ]);
+    }
 
-        let v: Vec<bool> = from_iter("[true]".chars()).unwrap();
-        assert_eq!(v, vec![true]);
+    #[test]
+    fn test_json_deserialize_list() {
+        test_json_deserialize_ok([
+            vec!(),
+            vec!(()),
+        ]);
 
-        let v: Vec<int> = from_iter("[3,1]".chars()).unwrap();
-        assert_eq!(v, vec![3, 1]);
+        test_json_deserialize_ok([
+            vec!(true),
+        ]);
 
-        let v: Vec<int> = from_iter("[ 3 , 1 ]".chars()).unwrap();
-        assert_eq!(v, vec![3, 1]);
+        test_json_deserialize_ok([
+            vec!(3, 1),
+        ]);
 
-        let v: Vec<Vec<uint>> = from_iter("[[3], [1, 2]]".chars()).unwrap();
-        assert_eq!(v, vec![vec![3], vec![1, 2]]);
+        test_json_deserialize_ok([
+            vec!(vec!(3), vec!(1, 2)),
+        ]);
     }
 
     /*
@@ -3179,8 +3363,8 @@ mod tests {
     */
 
     #[test]
-    fn test_decode_object() {
-        let errors = [
+    fn test_parse_object() {
+        test_parse_err::<TreeMap<String, int>>([
             ("{", SyntaxError(EOFWhileParsingString, 1, 2)),
             ("{ ", SyntaxError(EOFWhileParsingString, 1, 3)),
             ("{1", SyntaxError(KeyMustBeAString, 1, 2)),
@@ -3193,82 +3377,101 @@ mod tests {
             ("{\"a\":1 1", SyntaxError(InvalidSyntax, 1, 8)),
             ("{\"a\":1,", SyntaxError(EOFWhileParsingString, 1, 8)),
             ("{}a", SyntaxError(TrailingCharacters, 1, 3)),
-        ];
+        ]);
 
-        for &(s, err) in errors.iter() {
-            let v: Result<TreeMap<String, int>, ParserError> = from_iter(s.chars());
-            assert_eq!(v, Err(err));
-        }
+        test_parse_ok([
+            ("{}", treemap!()),
+            ("{ }", treemap!()),
+            (
+                "{\"a\":3}",
+                treemap!("a".to_string() => 3)
+            ),
+            (
+                "{ \"a\" : 3 }",
+                treemap!("a".to_string() => 3)
+            ),
+            (
+                "{\"a\":3,\"b\":4}",
+                treemap!("a".to_string() => 3, "b".to_string() => 4)
+            ),
+            (
+                "{ \"a\" : 3 , \"b\" : 4 }",
+                treemap!("a".to_string() => 3, "b".to_string() => 4),
+            ),
+        ]);
 
-        let v: TreeMap<String, int> = from_iter("{}".chars()).unwrap();
-        let m = TreeMap::new();
-        assert!(v == m);
-
-        let v: TreeMap<String, int> = from_iter("{ }".chars()).unwrap();
-        let m = TreeMap::new();
-        assert!(v == m);
-
-        let v: TreeMap<String, int> = from_iter("{\"a\":3}".chars()).unwrap();
-        let mut m = TreeMap::new();
-        m.insert("a".to_str(), 3);
-        assert!(v == m);
-
-        let v: TreeMap<String, int> = from_iter("{\"a\" :3}".chars()).unwrap();
-        let mut m = TreeMap::new();
-        m.insert("a".to_str(), 3);
-        assert!(v == m);
-
-        let v: TreeMap<String, int> = from_iter("{\"a\" : 3}".chars()).unwrap();
-        let mut m = TreeMap::new();
-        m.insert("a".to_str(), 3);
-        assert!(v == m);
-
-        let v: TreeMap<String, int> = from_iter("{\"a\": 3, \"b\": 4}".chars()).unwrap();
-        let mut m = TreeMap::new();
-        m.insert("a".to_str(), 3);
-        m.insert("b".to_str(), 4);
-        assert!(v == m);
-
-        let v: TreeMap<String, int> = from_iter("{ \"a\": 3, \"b\": 4 }".chars()).unwrap();
-        let mut m = TreeMap::new();
-        m.insert("a".to_str(), 3);
-        m.insert("b".to_str(), 4);
-        assert!(v == m);
-
-        let v: TreeMap<String, TreeMap<String, int>> = from_iter("{\"a\": {\"b\": 3, \"c\": 4}}".chars()).unwrap();
-        let mut mm = TreeMap::new();
-        mm.insert("b".to_str(), 3);
-        mm.insert("c".to_str(), 4);
-        let mut m = TreeMap::new();
-        m.insert("a".to_str(), mm);
-        assert!(v == m);
+        test_parse_ok([
+            (
+                "{\"a\": {\"b\": 3, \"c\": 4}}",
+                treemap!("a".to_string() => treemap!("b".to_string() => 3, "c".to_string() => 4)),
+            ),
+        ]);
     }
 
     #[test]
-    fn test_decode_struct() {
-        let s = "{
-            \"inner\": [
-                { \"a\": null, \"b\": 2, \"c\": [\"abc\", \"xyz\"] }
-            ]
-        }";
-        let v: Outer = from_iter(s.chars()).unwrap();
-        assert_eq!(
-            v,
+    fn test_json_deserialize_object() {
+        test_json_deserialize_ok([
+            treemap!(),
+            treemap!("a".to_string() => 3),
+            treemap!("a".to_string() => 3, "b".to_string() => 4),
+        ]);
+
+        test_json_deserialize_ok([
+            treemap!("a".to_string() => treemap!("b".to_string() => 3, "c".to_string() => 4)),
+        ]);
+    }
+
+    #[test]
+    fn test_parse_struct() {
+        test_parse_ok([
+            (
+                "{
+                    \"inner\": []
+                }",
+                Outer {
+                    inner: vec![]
+                },
+            ),
+            (
+                "{
+                    \"inner\": [
+                        { \"a\": null, \"b\": 2, \"c\": [\"abc\", \"xyz\"] }
+                    ]
+                }",
+                Outer {
+                    inner: vec![
+                        Inner { a: (), b: 2, c: vec!["abc".to_string(), "xyz".to_string()] }
+                    ]
+                },
+            )
+        ]);
+    }
+
+    #[test]
+    fn test_json_deserialize_struct() {
+        test_json_deserialize_ok([
             Outer {
                 inner: vec![
                     Inner { a: (), b: 2, c: vec!["abc".to_string(), "xyz".to_string()] }
                 ]
-            }
-        );
+            },
+        ]);
     }
 
     #[test]
-    fn test_decode_option() {
-        let value: Result<Option<String>, ParserError> = from_iter("null".chars());
-        assert_eq!(value, Ok(None));
+    fn test_parse_option() {
+        test_parse_ok([
+            ("null", None),
+            ("\"jodhpurs\"", Some("jodhpurs".to_string())),
+        ]);
+    }
 
-        let value: Result<Option<String>, ParserError> = from_iter("\"jodhpurs\"".chars());
-        assert_eq!(value, Ok(Some("jodhpurs".to_string())));
+    #[test]
+    fn test_json_deserialize_option() {
+        test_json_deserialize_ok([
+            None,
+            Some("jodhpurs".to_string()),
+        ]);
     }
 
         /*