rust: use i32 type in Value

[axic]

Depends on #517.

[axic]

The confusing fact is that even though it is called i32, the type is u32 in the bindgen translated fizzy.h.

[codecov]

Codecov Report

Merging #702 (1c10042) into master (d483edf) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #702   +/-   ##
=======================================
  Coverage   99.31%   99.31%           
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  Files          72       72           
  Lines       10628    10628           
=======================================
  Hits        10555    10555           
  Misses         73       73           

Flag	Coverage Δ
spectests	90.84% <ø> (ø)
unittests	99.31% <ø> (ø)

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[gumb0]

It looks like no unit tests use i64 now (neither floating point types)

Consider adding tests for Value conversions.

[axic]

Sure, but what test exactly? Neither Value or sys::FizzyValue is typed so not sure what is an appropriate test.

[axic]

This is the kind of test we could have (this passes, at least on my CPU/FPU):

    #[test]
    fn value_conversions() {
        let v:Value = i32::MIN.into();
        assert_eq!(v.as_i32(), i32::MIN);
        assert_eq!(v.as_u32(), 2147483648);
        assert_eq!(v.as_i64(), 2147483648);
        assert_eq!(v.as_u64(), 2147483648);
        assert_eq!(v.as_f32(), -0.0);
        assert_eq!(v.as_f64(), 0.000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010609978955);