Do not access .size field in DataType

[eschnett]

Closes https://github.com/JuliaIO/JLD2.jl/issues/428.

[codecov[bot]]

Codecov Report

Base: 84.09% // Head: 84.07% // Decreases project coverage by -0.02% :warning:

Coverage data is based on head (904a3e6) compared to base (cdf2ab8). Patch coverage: 88.88% of modified lines in pull request are covered.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #438 +/- ## ========================================== - Coverage 84.09% 84.07% -0.03% ========================================== Files 30 30 Lines 4113 4119 +6 ========================================== + Hits 3459 3463 +4 - Misses 654 656 +2 ``` | [Impacted Files](https://codecov.io/gh/JuliaIO/JLD2.jl/pull/438?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=JuliaIO) | Coverage Δ | | |---|---|---| | [src/data/type\_defs.jl](https://codecov.io/gh/JuliaIO/JLD2.jl/pull/438/diff?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=JuliaIO#diff-c3JjL2RhdGEvdHlwZV9kZWZzLmps) | `88.88% <71.42%> (-11.12%)` | :arrow_down: | | [src/data/number\_types.jl](https://codecov.io/gh/JuliaIO/JLD2.jl/pull/438/diff?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=JuliaIO#diff-c3JjL2RhdGEvbnVtYmVyX3R5cGVzLmps) | `73.68% <100.00%> (ø)` | | | [src/data/reconstructing\_datatypes.jl](https://codecov.io/gh/JuliaIO/JLD2.jl/pull/438/diff?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=JuliaIO#diff-c3JjL2RhdGEvcmVjb25zdHJ1Y3RpbmdfZGF0YXR5cGVzLmps) | `76.43% <100.00%> (ø)` | | | [src/data/writing\_datatypes.jl](https://codecov.io/gh/JuliaIO/JLD2.jl/pull/438/diff?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=JuliaIO#diff-c3JjL2RhdGEvd3JpdGluZ19kYXRhdHlwZXMuamw=) | `96.84% <100.00%> (ø)` | | Help us with your feedback. Take ten seconds to tell us [how you rate us](https://about.codecov.io/nps?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=JuliaIO). Have a feature suggestion? [Share it here.](https://app.codecov.io/gh/feedback/?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=JuliaIO)

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[eschnett]

The failing check is a spurious small apparent reduction in coverage because codecov miscounts some function metadata. There is no actual reduction in coverage.

[JonasIsensee]

Hi @eschnett, thanks a lot for figuring this out!

[IanButterworth]

This issue resurfaced because julia compat was not updated https://github.com/JuliaRegistries/General/pull/93505

[giordano]

It'd be appreciated if package developers proactively added appropriate compat bounds in the registry to avoid troubles to users, when they fix errors like this one.

[JonasIsensee]

Hi @giordano ,

I'm aware of the problem but don't have a proper solution.

Can I limit the compat on Julia (by default on the current minor version) without preventing tests on nightly?

Should I just manually keep track of problems and make handcrafted pull requests to the registry?

[giordano]

We already fixed it in the PR linked above: https://github.com/JuliaRegistries/General/pull/93505. That was more a suggestion for the future.

[JonasIsensee]

Sure, I was just wondering whether I can prevent his from happening again or whether the best/only option is for me to create such a PR next time.

The current JLD2 release claims to be compatible with all future 1.x releases which is probably not correct. (Since it relies on Julia internals and I don't think it's possible to get rid of this entirely)

[giordano]

Ideally you wouldn't use julia's internals. If that's really not possible, when you become aware of some breakage, like #428, it'd be good to do a PR to General like the one linked above, to prevent the package to be installed on incompatible versions of julia.