Avoid extending `Type` from Base on Julia 1.12

[ararslan]

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The internal Flatbuf module defines a function called Type. On Julia 1.12, defining a new function by defining methods is insufficient to distinguish it from defining new constructor methods for a visible type of the same name. It's now necessary to forward-declare the function to ensure it takes precedence over the other visible binding. Without doing so, Base.Type is extended in Flatbuf instead.

On current main with Julia v1.13.0-DEV.122:

julia> using Arrow
Info Given Arrow was explicitly requested, output will be shown live
WARNING: Constructor for type "Type" was extended in `Flatbuf` without explicit qualification or import.
  NOTE: Assumed "Type" refers to `Base.Type`. This behavior is deprecated and may differ in future versions.
  NOTE: This behavior may have differed in Julia versions prior to 1.12.
  Hint: If you intended to create a new generic function of the same name, use `function Type end`.
  Hint: To silence the warning, qualify `Type` as `Base.Type` in the method signature or explicitly `import Base: Type`.
Precompiling Arrow finished.
  1 dependency successfully precompiled in 4 seconds. 47 already precompiled.
  1 dependency had output during precompilation:
┌ Arrow
│  [Output was shown above]
└

julia> methods(Type)
# 2 methods for type constructor:
 [1] Type(b::UInt8)
     @ Arrow.Flatbuf ~/Projects/julia-packages/arrow-julia/src/metadata/Schema.jl:489
 [2] Type(::Type{T}) where T
     @ Arrow.Flatbuf ~/Projects/julia-packages/arrow-julia/src/metadata/Schema.jl:519

julia> Arrow.Flatbuf.Type === Type
[ Warning: Type is defined in Core and is not public in Arrow.Flatbuf
true

With this PR, the output is the same because of https://github.com/JuliaLang/julia/issues/57546 but will have the correct behavior once that issue is fixed.

[codecov-commenter]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 86.96%. Comparing base (3712291) to head (9eb80c1). :warning: Report is 32 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #543      +/-   ##
==========================================
- Coverage   87.43%   86.96%   -0.48%     
==========================================
  Files          26       27       +1     
  Lines        3288     3398     +110     
==========================================
+ Hits         2875     2955      +80     
- Misses        413      443      +30     

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[ufechner7]

Same problem on Julia 1.12-beta3

[kou]

Could you rebase on main to re-run CI?

[ararslan]

@kou, I've rebased.

[kou]

Hmm... CI isn't executed... Could you re-rebase...?

[ararslan]

Done, but I still don't see CI status. Is the repository configured such that CI is not run on PRs from forks?

[kou]

Thanks. I can approve CI execution for "first-time contributor" now. I've approved now. Let's see the CI result with this change.

[ararslan]

Looks like CI fails on Julia nightly with multiple threads, but not in a way that could plausibly be related to the changes here, so I think we're okay.

[kou]

@quinnj @ericphanson @baumgold Can we merge this?

[kou]

@quinnj @ericphanson @baumgold I'll merge this in the next week if nobody objects it.

[palday]

@kou please merge since 1.12 is now RC2 ❤️

[kou]

Merged. Should we release a new version before Julia 1.12 release?

[palday]

@kou yes!

[kou]

OK. Let's discuss it in #567.