feat: expand the usefulness of resource_sets

[novas0x2a]

This adds a new public function, resource_set_for, which takes a cpu and memory value and returns an appropriate resource_set function for those values, adding some support for the cross-product mentioned in the previous pass. The bazel resource_set API isn't very easy to work with, and this hides the ugliness here, rather than expecting every module to implement something like rules_rust did.

The ugliness of the implementation is mitigated slightly by using a helper script to generate it, and I reason that people attempting to use the resource_set API would be better off with additional abstraction, so if/when this gets fixed in bazel, most people don't need to notice.

[aspect-workflows]

Bazel 8 (Test)

2 test targets passed

Targets

//lib/tests/copy_to_directory:case_22_test [k8-fastbuild]                    185ms
//lib/tests/copy_to_directory_bin_action:test [k8-fastbuild]                 73ms

Total test execution time was 258ms. 134 tests (98.5%) were fully cached saving 42s.

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Bazel 9 (Test)

2 test targets passed

Targets

//lib/tests/copy_to_directory:case_22_test [k8-fastbuild]                    156ms
//lib/tests/copy_to_directory_bin_action:test [k8-fastbuild]                 235ms

Total test execution time was 391ms. 134 tests (98.5%) were fully cached saving 55s.

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Bazel 7 (Test)

e2e/api_entries

All tests were cache hits

1 test (100.0%) was fully cached saving 23ms.

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Bazel 8 (Test)

e2e/api_entries

All tests were cache hits

1 test (100.0%) was fully cached saving 23ms.

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Bazel 9 (Test)

e2e/api_entries

All tests were cache hits

1 test (100.0%) was fully cached saving 24ms.

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Bazel 7 (Test)

e2e/copy_action

All tests were cache hits

1 test (100.0%) was fully cached saving 20ms.

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Bazel 8 (Test)

e2e/copy_action

All tests were cache hits

1 test (100.0%) was fully cached saving 21ms.

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Bazel 9 (Test)

e2e/copy_action

All tests were cache hits

1 test (100.0%) was fully cached saving 37ms.

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Bazel 7 (Test)

e2e/copy_to_directory

All tests were cache hits

6 tests (100.0%) were fully cached saving 309ms.

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Bazel 8 (Test)

e2e/copy_to_directory

All tests were cache hits

6 tests (100.0%) were fully cached saving 295ms.

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Bazel 9 (Test)

e2e/copy_to_directory

All tests were cache hits

6 tests (100.0%) were fully cached saving 349ms.

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Bazel 7 (Test)

e2e/coreutils

All tests were cache hits

4 tests (100.0%) were fully cached saving 204ms.

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Bazel 8 (Test)

e2e/coreutils

All tests were cache hits

4 tests (100.0%) were fully cached saving 260ms.

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Bazel 9 (Test)

e2e/coreutils

All tests were cache hits

4 tests (100.0%) were fully cached saving 191ms.

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Bazel 7 (Test)

e2e/external_copy_to_directory

All tests were cache hits

1 test (100.0%) was fully cached saving 20ms.

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Bazel 8 (Test)

e2e/external_copy_to_directory

All tests were cache hits

1 test (100.0%) was fully cached saving 21ms.

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Bazel 9 (Test)

e2e/external_copy_to_directory

All tests were cache hits

1 test (100.0%) was fully cached saving 37ms.

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Bazel 7 (Test)

e2e/smoke

All tests were cache hits

4 tests (100.0%) were fully cached saving 415ms.

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Bazel 8 (Test)

e2e/smoke

All tests were cache hits

4 tests (100.0%) were fully cached saving 636ms.

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Bazel 9 (Test)

e2e/smoke

All tests were cache hits

4 tests (100.0%) were fully cached saving 872ms.

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Bazel 7 (Test)

e2e/write_source_files

All tests were cache hits

1 test (100.0%) was fully cached saving 30ms.

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Bazel 8 (Test)

e2e/write_source_files

All tests were cache hits

1 test (100.0%) was fully cached saving 28ms.

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Bazel 9 (Test)

e2e/write_source_files

All tests were cache hits

1 test (100.0%) was fully cached saving 33ms.

[novas0x2a]

As a follow-up, here are some of the other things I was looking at doing:

1. making resource_set respond to tags as well as the attribute, as in: cpu:<small|medium|large|enormous>, cpu:<cores:int>, mem:<small|medium|large|enormous>, mem:<num:int><m|g> (i could be convinced to drop cpu:<int> and mem:<int> in favor of just having the symbolic sizes, though that'd represent a compat break if i did that for the attr, too)
2. provide some sort of tuning mechanism to allow end users to configure what the sizes mean (as in: all "larges" are given 8 cores: e.g. //setting:cpu_large=8; this is important to give users an out for projects overtuning for large ci machines)
3. finally, I plan to integrate this into rules_foreign_cc and sync it with the underlying build systems, defaulting (e.g.) CMAKE_BUILD_PARALLEL_LEVEL to the resource_set's cpu request.

I'm interested in helping achieve cross-consistency for these behaviors, which means I'd like (at least) 1 to be handled in bazel-lib, and maybe 2 if there's consensus.