perf: reduce use of bazel_skylib paths.join

[jbedard]

In most scenarios we don't need all the logic detecting empty segments or detecting absolute paths in individual parts.

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Changes are visible to end-users: no

Test plan

• Covered by existing test cases

[aspect-workflows]

Test

3 test targets passed

Targets

//npm/private/test:bin_test [k8-fastbuild]                     2s
//npm/private:_test_gendocs_0_0 [k8-fastbuild]                 210ms
//npm/private:_test_gendocs_0_1 [k8-fastbuild]                 181ms

Total test execution time was 2s. 190 tests (98.4%) were fully cached saving 37s.

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Test

e2e/bzlmod

All tests were cache hits

4 tests (100.0%) were fully cached saving 486ms.

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Test

e2e/gyp_no_install_script

All tests were cache hits

2 tests (100.0%) were fully cached saving 557ms.

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Test

e2e/js_image_oci

All tests were cache hits

1 test (100.0%) was fully cached saving 7s.

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Test

e2e/npm_link_package

All tests were cache hits

2 tests (100.0%) were fully cached saving 1s.

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Test

e2e/npm_link_package-esm

All tests were cache hits

2 tests (100.0%) were fully cached saving 923ms.

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Test

e2e/npm_translate_lock

All tests were cache hits

1 test (100.0%) was fully cached saving 73ms.

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Test

e2e/npm_translate_lock_empty

All tests were cache hits

1 test (100.0%) was fully cached saving 73ms.

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Test

e2e/npm_translate_lock_multi

All tests were cache hits

2 tests (100.0%) were fully cached saving 271ms.

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Test

e2e/npm_translate_lock_partial_clone

All tests were cache hits

1 test (100.0%) was fully cached saving 117ms.

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Test

e2e/npm_translate_lock_subdir_patch

All tests were cache hits

1 test (100.0%) was fully cached saving 251ms.

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Test

e2e/npm_translate_package_lock

All tests were cache hits

1 test (100.0%) was fully cached saving 73ms.

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Test

e2e/npm_translate_yarn_lock

All tests were cache hits

1 test (100.0%) was fully cached saving 73ms.

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Test

e2e/package_json_module

All tests were cache hits

1 test (100.0%) was fully cached saving 566ms.

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Test

e2e/pnpm_lockfiles

All tests were cache hits

28 tests (100.0%) were fully cached saving 10s.

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Test

e2e/pnpm_workspace

All tests were cache hits

8 tests (100.0%) were fully cached saving 3s.

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Test

e2e/pnpm_workspace_rerooted

All tests were cache hits

6 tests (100.0%) were fully cached saving 3s.

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Test

e2e/repo_mapping

All tests were cache hits

2 tests (100.0%) were fully cached saving 453ms.

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Test

e2e/rules_foo

All tests were cache hits

2 tests (100.0%) were fully cached saving 605ms.

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Test

e2e/vendored_node

All tests were cache hits

1 test (100.0%) was fully cached saving 187ms.

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