fix(npm): correct use of pnpm lockfile dev flag

[jbedard]

Fix the usage of the lockfile dev flag, rename vars where possible to better indicate the meaning.

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Changes are visible to end-users: no

Test plan

• Covered by existing test cases
• Manual testing; please provide instructions so we can reproduce: jbedard@cf3f12a and toggling npm_translate_lock dev and prod flags.

[aspect-workflows]

Test

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212 tests (100.0%) were fully cached saving 37s.

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Test

e2e/bzlmod

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5 tests (100.0%) were fully cached saving 502ms.

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Test

e2e/gyp_no_install_script

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2 tests (100.0%) were fully cached saving 172ms.

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Test

e2e/js_image_oci

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1 test (100.0%) was fully cached saving 9s.

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e2e/npm_link_package

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3 tests (100.0%) were fully cached saving 555ms.

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Test

e2e/npm_link_package-esm

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3 tests (100.0%) were fully cached saving 575ms.

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e2e/npm_translate_lock

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1 test (100.0%) was fully cached saving 22ms.

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Test

e2e/npm_translate_lock_empty

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1 test (100.0%) was fully cached saving 22ms.

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e2e/npm_translate_lock_multi

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2 tests (100.0%) were fully cached saving 97ms.

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e2e/npm_translate_lock_partial_clone

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1 test (100.0%) was fully cached saving 22ms.

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e2e/npm_translate_lock_replace_packages

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3 tests (100.0%) were fully cached saving 145ms.

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e2e/npm_translate_lock_subdir_patch

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1 test (100.0%) was fully cached saving 93ms.

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e2e/npm_translate_package_lock

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1 test (100.0%) was fully cached saving 26ms.

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Test

e2e/npm_translate_yarn_lock

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1 test (100.0%) was fully cached saving 26ms.

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Test

e2e/package_json_module

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1 test (100.0%) was fully cached saving 362ms.

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Test

e2e/pnpm_lockfiles

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

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e2e/pnpm_workspace

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10 tests (100.0%) were fully cached saving 4s.

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e2e/pnpm_workspace_rerooted

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

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Test

e2e/repo_mapping

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2 tests (100.0%) were fully cached saving 276ms.

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Test

e2e/rules_foo

All tests were cache hits

2 tests (100.0%) were fully cached saving 115ms.

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Test

e2e/runfiles

All tests were cache hits

1 test (100.0%) was fully cached saving 116ms.

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Test

e2e/vendored_node

All tests were cache hits

1 test (100.0%) was fully cached saving 181ms.

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Buildifier      Format

[dzbarsky]

nit: Maybe also consider "dev_only" or "only_dev", its a bit closer to testonly?