Json.Decode.keyValuePairs does not keep field order

[jinjor]

It looks Json.Decode.keyValuePairs returns fields in reversed order. I expect it keeps the order as they are defined.

> import Json.Decode as D
> import Json.Encode as E

> D.decodeString (D.keyValuePairs D.int) "{\"a\":1,\"b\":2}"
Ok [("b",2),("a",1)] : Result.Result String (List ( String, Int ))

> D.decodeString (D.keyValuePairs D.int) "{\"b\":1,\"a\":2}"
Ok [("a",2),("b",1)] : Result.Result String (List ( String, Int ))

> D.decodeString (D.keyValuePairs D.int) "{\"a\":1,\"b\":2, \"c\":3}"
Ok [("c",3),("b",2),("a",1)] : Result.Result String (List ( String, Int ))

> D.decodeValue (D.keyValuePairs D.int) (E.object [("a", E.int 1), ("b", E.int 2)])
Ok [("b",2),("a",1)] : Result.Result String (List ( String, Int ))

> D.decodeValue (D.keyValuePairs D.int) (E.object [("b", E.int 1), ("a", E.int 2)])
Ok [("a",2),("b",1)] : Result.Result String (List ( String, Int ))

I confirmed JavaScript works as I expected.

> Object.keys({a:1, b:2})
[ 'a', 'b' ]

> Object.keys({b:1, a:2})
[ 'b', 'a' ]

> Object.keys(JSON.parse('{"a":1, "b":2}')) 
[ 'a', 'b' ]

> Object.keys(JSON.parse('{"b":1, "a":2}')) 
[ 'b', 'a' ]

---

Elm: 0.18.0
elm-lang/core: 5.1.1
OS: macOS

[process-bot]

Thanks for the issue! Make sure it satisfies this checklist. My human colleagues will appreciate it!

Here is what to expect next, and if anyone wants to comment, keep these things in mind.

[process-bot]

Thanks for the issue! Make sure it satisfies this checklist. My human colleagues will appreciate it!

Here is what to expect next, and if anyone wants to comment, keep these things in mind.

[jinjor]

Oops, I found the correct spec is written here.

An object is an unordered collection of zero or more name/value
pairs, where a name is a string and a value is a string, number,
boolean, null, object, or array.

[jinjor]

Oops, I found the correct spec is written here.

An object is an unordered collection of zero or more name/value
pairs, where a name is a string and a value is a string, number,
boolean, null, object, or array.