stricter shapes for setindex

[adienes]

not now ambitious enough to claim this fixes #40018, but let's just say I wrote it while reading the issue

fixes JuliaSparse/SparseArrays.jl#569
updates #45374 (closes?)

[giordano]

not ambitious enough to claim this fixes #40018

By writing that you automatically marked this PR to close that issue anyway. If you don't want to do that, put something between "fixes" and "#40018", like "issue".

[adienes]

I (believe) this implements the idea in #40018 (comment)

I really hope it isn't a performance trainwreck

edit: BitArray needs fixing

[adienes]

JuliaSparse/SparseArrays.jl#637

would fix the sparsearrays test case

looks like there was some previous discussion in #43644

[adienes]

@nanosoldier runtests()

[nanosoldier]

The package evaluation job you requested has completed - possible new issues were detected.
The full report is available.

Report summary

✖ Packages that failed

9 packages failed only on the current version.

• Package has test failures: 1 packages
• Package tests unexpectedly errored: 5 packages
• Test duration exceeded the time limit: 3 packages

16 packages failed on the previous version too.

✔ Packages that passed tests

3 packages passed tests only on the current version.

• Other: 3 packages

58 packages passed tests on the previous version too.

~ Packages that at least loaded

3 packages successfully loaded only on the current version.

• Other: 3 packages

24 packages successfully loaded on the previous version too.

[adienes]

that's better. so there are ~5 real failures, all of which are trying to drop non-trailing singleton dimensions besides Vlasiator.jl, which gets
DimensionMismatch: tried to assign 3×8192 array to 3×32×16×16 destination

FYI I tried to outline the error path, but it looks like there are bootstrap issues with @noinline to annotate functions, so I had to remove it.

[adienes]

triage also considered the fact that this implementation would allow I or X in an A[I] = X expression to have differently-offset axes so long as the size matches the rule here, and was cautiously ok with that

[jishnub]

Just to clarify: ignoring the axes offset in setindex! seems to be what we already do (#45374), and this PR doesn't change anything here?

[adienes]

correct; this PR should not change the behavior of the MWE there

julia> a = [1:7;];

julia> a[Base.IdentityUnitRange(3:4)] = 2:3
2:3

although it may add documentation clarifying that this is allowed

[mbauman]

I threw a commit on here that tries to document this; it's just meant to be a starting point.

[adienes]

not to add another wrinkle but should this PR also remove the require_one_based_indexing here ?

julia/base/array.jl

Line 1028 in 13f6b3b

require_one_based_indexing(X)

if we are going to really commit to "sizes must match, axes need not" decision

[adienes]

I will need help coordinating with JuliaSparse/SparseArrays.jl#637

[adienes]

I'm going to run a bunch of benchmarks for setindex! across various sizes / dimensionalities / array types / eltypes etc. and if I don't see any regressions or hear any new feedback about the added docs / news, I'll follow the plan in JuliaSparse/SparseArrays.jl#637 (comment) to get it merged