[xkykai]

find_λ_range uses floor(λ / 360) in place of the hand-built floor division ifelse((λ < 0) & (mod(λ, 360) != 0), λ ÷ 360 - 1, λ ÷ 360), so interpolate! compiles on Metal for Float32 LatitudeLongitudeGrids.

On Julia ≥ 1.12, ÷ and fld on Float32 go through Float64 (JuliaGPU/Metal.jl#972), which Metal can't compile. The upstream fix, JuliaGPU/Metal.jl#975, needs Metal ≥ 1.10.1, which needs GPUCompiler 2, and Enzyme and Reactant cap it at 1.x. floor(λ / 360) matches fld(λ, 360) for every Float32 with 2.5e-43 < |λ| < 1.9e8 on the CPU.

• Adds a Metal test that interpolates between Float32 LatitudeLongitudeGrids with longitudes (-180, 180) and (0, 360).
• A TODO at find_λ_range to switch to fld once Oceananigans can use a Metal release with the fix.

Closes #6056

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 74.84%. Comparing base (2429a6a) to head (efa542f).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6057      +/-   ##
==========================================
+ Coverage   74.83%   74.84%   +0.01%     
==========================================
  Files         439      439              
  Lines       27385    27382       -3     
==========================================
+ Hits        20493    20494       +1     
+ Misses       6892     6888       -4     

Flag	Coverage Δ
buildkite	70.55% <100.00%> (+<0.01%)	⬆️
distributed_tripolar	20.55% <0.00%> (ø)
julia	70.55% <100.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.