output of json encode/decode of structs containing f64 arrays is not equivalent to the input

[holder66]

Describe the bug

Applying json.encode and then json.decode to a struct containing an f64 array generates an output which is no longer equivalent to the input.
It appears to be related to how and where rounding is done.

Reproduction Steps

module main

import json

struct Test {
mut:
	arr []f64
}

fn main() {
	mut a := Test{}
	a.arr = [0.9716157205240175, 0.9336099585062241]
	println(a)
	mut enc := json.encode(a)
	println(enc)
	println(json.decode(Test, enc)!)
	println(a == json.decode(Test, enc)!)
}

Expected Behavior

the input should be equivalent to the output

Current Behavior

Test{
    arr: [0.9716157205240175, 0.9336099585062241]
}
{"arr":[0.97161572052401746,0.933609958506224]}
Test{
    arr: [0.9716157205240175, 0.933609958506224]
}
false

Possible Solution

No response

Additional Information/Context

No response

V version

V 0.4.8 df51e84, timestamp: 2024-11-14 13:58:50 +0200

Environment details (OS name and version, etc.)

V full version: V 0.4.8 dad8e3c.df51e84
OS: macos, macOS, 15.0.1, 24A348
Processor: 16 cpus, 64bit, little endian, Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz

getwd: /Users/henryolders
vexe: /Users/henryolders/v/v
vexe mtime: 2024-11-14 15:14:24

vroot: OK, value: /Users/henryolders/v
VMODULES: OK, value: /Users/henryolders/.vmodules
VTMP: OK, value: /tmp/v_507

env VFLAGS: "-use-os-system-to-run"

Git version: git version 2.47.0
Git vroot status: weekly.2024.06-1635-gdf51e840
.git/config present: true

CC version: Apple clang version 16.0.0 (clang-1600.0.26.4)
emcc version: N/A
thirdparty/tcc status: thirdparty-macos-amd64 975f1ad8

Note

You can use the 👍 reaction to increase the issue's priority for developers.

Please note that only the 👍 reaction to the issue itself counts as a vote.
Other reactions and those to comments will not be taken into account.