install: key the extraction cache slot by the registry URL, not only its hostname

[robobun]

Problem

• The npm extraction cache folder is <name>@<version>@@<hostname>@@@1, and the hostname is the configured registry's. Two registries on one host share a slot: a Nexus or Artifactory repository path, a CodeArtifact repository, two Verdaccio ports. The first registry to extract foo@1.0.0 serves every later project configured for the other one. That project issues no tarball request, links the other registry's bytes, writes its own registry's sha512 into bun.lock, and runs the other registry's postinstall when foo is in trustedDependencies.
• A lockfile that pins another registry's tarball URL has the same effect across hostnames: the install downloads the pinned URL and extracts it into the configured registry's slot.
• Cause: cached_npm_package_folder_name_print (src/install/PackageManager/PackageManagerDirectories.rs) names the slot after scope_for_package_name(name).url.hostname alone.

Fix

• A package on a non-default registry lives in <name>@<version>@@<host>__<16 hex>@@@1, where the hex is scope.url_hash, the hash of the whole registry URL that already names the packument cache (*.npm). Port and path now tell registries apart. A package on the default registry keeps <name>@<version>@@@1.
• Every site that names a slot passes the package's tarball URL (resolution.npm().url). A tarball on the configured registry or on registry.npmjs.org gets the registry's slot. A tarball on neither (a lockfile written against another registry) gets @@<tarball host>__<hash of the tarball URL>, so it never fills the configured registry's slot.
• bun.lock writes an npmjs tarball URL as "" and rebuilds it under the configured registry on the next install. Both spellings resolve to the registry's slot, so the lockfile round-trip stays a cache hit (asserted in the test).
• Verified: test/cli/install/bun-install.test.ts (registries that share a hostname, three tests, all fail on the unfixed build). Also bun-install-registry.test.ts, bun-add.test.ts, bun-patch.test.ts, isolated-install.test.ts, bun-install-offline.test.ts, config-precedence.test.ts, and test/cli/run/run-autoinstall.test.ts.

Background

• The install cache (~/.bun/install/cache or BUN_INSTALL_CACHE_DIR) is shared by every project on a machine. A package is extracted once into a folder there, and installs link out of it. A cache hit is a directory probe, so the folder name is the only thing that ties a slot to its origin.
• The cache is keyed by resolution identity and verifies bytes once, at fetch (the model written down when install: key npm cache entries by their integrity, derive URL-based cache names with SHA-256 #37756 was closed). For an npm package that identity is the registry plus name@version. This change makes the key carry the whole registry URL instead of its hostname. It does not add content hashes to the key.
• bun.lock writes a non-npmjs tarball URL verbatim, and an install honors it even when bunfig.toml now names another registry. That is the one case where the tarball URL, not the configured registry, names the slot.

Notes

Reproduction (two stub registries on one host, the second on a different port and path):

W=$(mktemp -d); cd $W; export HOME=$W/home BUN_INSTALL_CACHE_DIR=$W/cache; mkdir -p $HOME
# reg.js: serves /<prefix>/foo and /<prefix>/foo/-/foo-1.0.0.tgz, index.js exports the variant name
node reg.js 4873 /npm-public PUBLIC & node reg.js 4874 /npm-private PRIVATE &
for p in A B; do mkdir $p; echo '{"name":"'$p'","dependencies":{"foo":"1.0.0"}}' > $p/package.json; done
printf '[install]\nregistry = "http://127.0.0.1:4873/npm-public/"\n'  > A/bunfig.toml
printf '[install]\nregistry = "http://127.0.0.1:4874/npm-private/"\n' > B/bunfig.toml
(cd A && bun install && bun -p 'require("foo")')   # PUBLIC
(cd B && bun install && bun -p 'require("foo")')   # before: PUBLIC, one foo@1.0.0@@127.0.0.1@@@1
                                                   # after: PRIVATE, foo@1.0.0@@127.0.0.1__<hex>@@@1 per registry

Slot names:

• foo@1.0.0@@@1: default registry (unchanged).
• foo@1.0.0@@nexus.corp__<16 hex>@@@1: non-default registry, hex = hash of the registry URL (the same url_hash as in <id>-<url_hash>.npm).
• foo@1.0.0@@other.host__<16 hex>@@@1: tarball URL that is on neither the configured registry nor npmjs, hex = hash of that URL.

Every slot on a non-default registry moves once (from @@host@@@1 to @@host__hex@@@1), so an existing cache fetches each such package one more time. Default-registry slots are untouched.

The <cache>/<name>/<version>... index symlink follows the slot name. path_for_cached_npm_path takes the tarball URL too. resolve_from_disk_cache (--prefer-offline auto-install) passes an empty URL and gets the registry's slot. That path did not resolve a non-default-registry package before this change either, and is tracked separately. bun install --offline is a different path and is covered by bun-install-offline.test.ts.

History of this PR: the first revision keyed the slot by the lockfile integrity. It was reworked because that is the "subset, not a model" shape the #37756 close note rejected, because it needed an integrity parameter on compute_cache_dir_and_subpath that #39016 also adds with a different encoding, and because a registry-keyed name is derivable from the lockfile row alone. A second revision keyed by the raw tarball URL; review found that bun.lock normalizes an npmjs tarball URL to "", which would have split one package across two slots for a mirror whose packuments point at npmjs, so the registry URL is the key and the tarball URL only decides whether the tarball belongs to that registry.

VerdaccioRegistry.cacheFolderName(cacheDir, name, version) in test/harness.ts finds the slot by pattern for the three existing tests that asserted @@localhost@@@1.

Test runs with the debug build: bun-install.test.ts fails only the tests that need the public internet (bitbucket, gitlab, https://some.url), same as main. config-precedence.test.ts and bun-run-dir.test.ts time out at the 5 s default under the debug build on main as well and pass with --timeout 120000.

[coderabbitai]

Walkthrough

NPM cache naming now includes resolved tarball URLs for non-default registries. Cache path callers propagate lockfile and package resolution URLs. Tests validate separate cache entries for registries with different paths or ports.

Changes

NPM cache identity

Layer / File(s)	Summary
URL-aware cache naming src/install/PackageManager/PackageManagerDirectories.rs	NPM cache names preserve default-registry behavior and use the parsed hostname plus a hash of non-default tarball URLs.
Resolution URL propagation src/install/PackageManager/PackageManagerDirectories.rs, src/install/PackageManager/PackageManagerLifecycle.rs, src/install/PackageManager/PackageManagerResolution.rs, src/install/PackageInstaller.rs, src/install/extract_tarball.rs, src/install/isolated_install.rs, src/install/isolated_install/Installer.rs	Lockfile and package resolution flows pass tarball URLs into NPM cache path generation.
Cache isolation validation test/cli/install/bun-install-registry.test.ts, test/cli/install/bun-install.test.ts, test/cli/install/config-precedence.test.ts, test/harness.ts	Tests derive cache paths through registry helpers and validate isolation across registry paths and ports, including frozen-lockfile installs.

Suggested reviewers: jarred-sumner, alii

Merge Risk: 🟠 High · up to e36db

Offline installs can fail despite the requested package already being cached from a non-default registry. This should be fixed before merge.

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title clearly and concisely describes the main change: extraction cache slots are keyed by the registry URL instead of only the hostname.
Description check	✅ Passed	The description clearly explains the problem, implementation, behavior, risks, and verification results. It does not use the exact template headings, but it provides the required content through equiv…

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[robobun]

^{Updated 11:27 AM PT - Sep 6th, 2026}

⏳ @robobun, your commit 3080a68 is still building in Build #111627, but has 1 failures so far (All Failures):

• test/js/node/test/parallel/test-crypto-dh-leak.js - code 1 on 🐧 13 x64-asan

[robobun]

Status: reproduced with two stub registries on one host (different port and path). Project B linked project A's bytes with no tarball request, and wrote its own registry's sha512 into bun.lock. With this branch, B fetches its own tarball and the cache holds one slot per registry URL. Verified with the new tests in test/cli/install/bun-install.test.ts (registries that share a hostname), which fail on the unfixed build.

Current shape (3080a68): the slot of a non-default-registry package is keyed by the full registry URL (the same url_hash as the packument cache). A tarball that a lockfile pins to some other registry is keyed by its own URL. Default-registry slots are unchanged.

CI (build 111627): every lane that ran this diff's tests is green. The one red job is test/js/node/test/parallel/test-crypto-dh-leak.js on debian x64-asan, which fails on main as well. The two darwin x64 test jobs expired waiting for an agent and did not run. Ready for review.

[claude]

Nothing blocking. The comments below are optional suggestions. There is no need to push a fix for them before merging.

[coderabbitai]

Actionable comments posted: 1

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Inline comments:
In `@src/install/PackageManager/PackageManagerResolution.rs`:
- Line 204: Update resolve_from_disk_cache to preserve and pass the discovered
cache directory entry or URL-derived key from
get_installed_versions_from_disk_cache instead of b"". Ensure
path_for_cached_npm_path selects the discovered non-default-registry cache slot
so readlinkat can find the cached package during offline resolution.

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📥 Commits

Reviewing files that changed from the base of the PR and between d316760 and e36dbd0.

📒 Files selected for processing (11)

• src/install/PackageInstaller.rs
• src/install/PackageManager/PackageManagerDirectories.rs
• src/install/PackageManager/PackageManagerLifecycle.rs
• src/install/PackageManager/PackageManagerResolution.rs
• src/install/extract_tarball.rs
• src/install/isolated_install.rs
• src/install/isolated_install/Installer.rs
• test/cli/install/bun-install-registry.test.ts
• test/cli/install/bun-install.test.ts
• test/cli/install/config-precedence.test.ts
• test/harness.ts

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[claude]

Nothing blocking. The comments below are optional suggestions. There is no need to push a fix for them before merging.

[claude]

Code review found no issues

No high-confidence issues detected in this change.

[claude]

Code review found no issues

No high-confidence issues detected in this change.