Converting Dates.FixedPeriod to Quantity{...,𝐓}

[mcabbott]

Fixes #125, or at least makes a start.

Edit: I moved this to a new file, as it needs to come after the relevant units have been defined.

julia> uconvert(s, Microsecond(1))
1//1000000 s

julia> convert(typeof(1f0s), Minute(1))
60.0f0 s

julia> promote(Minute(1), 1s) 
(60 s, 1 s)

Should things like this be made to work?

julia> Minute(1) + 1s
ERROR: MethodError: no method matching +(::Minute, ::Quantity{Int64,𝐓,Unitful.FreeUnits{(s,)

[sostock]

I also started to implement this some time ago, I have uploaded it here so you can maybe use some of my code:

https://gist.github.com/sostock/68e5eda1abee911116dcc08970843d0c

The broken tests should work on Julia ≥ 1.5, since JuliaLang/julia#34645 was fixed recently.

[mcabbott]

OK, perhaps I should close this in favour of that, you've taken this far more seriously.

Would the plan be to just not run those tests on Julia < 1.5?

[codecov-io]

Codecov Report

Merging #329 into master will decrease coverage by 0.25%.
The diff coverage is 65.00%.

@@            Coverage Diff             @@
##           master     #329      +/-   ##
==========================================
- Coverage   80.23%   79.98%   -0.26%     
==========================================
  Files          15       16       +1     
  Lines        1174     1194      +20     
==========================================
+ Hits          942      955      +13     
- Misses        232      239       +7     

Impacted Files	Coverage Δ
src/Unitful.jl	100.00% <ø> (ø)
src/dates.jl	65.00% <65.00%> (ø)

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[sostock]

OK, perhaps I should close this in favour of that, you've taken this far more seriously.

If you want, I can make a PR with my changes. I think I didn’t do that because I wanted to implement some more stuff (like support for CompoundPeriods) before making a PR.

Would the plan be to just not run those tests on Julia < 1.5?

Yes, that’s how I would do it.

[mcabbott]

OK, no great rush, but having even the basics would be nice.

[sostock]

I opened #331 as a replacement.