install: drop the query string and fragment from a tarball URL's extraction folder name

[robobun]

Problem

• bun add http://host/pkg-1.0.0.tgz?token=abc fails on Windows. Any tarball URL with a query string does; the same URL without one installs fine, and so does the same URL declared under a name in package.json:

  error: ENOENT when create temporary directory named ".2fabfa77918bdd48-1.pkg-1.0.0.tgz?token=abc" (while extracting "http://host/pkg-1.0.0.tgz?token=abc")
  error: InstallFailed extracting tarball from http://host/pkg-1.0.0.tgz?token=abc
  

  With the streaming extractor (bodies of 2 MiB or more) the first line is ENOENT extracting tarball for "<url>" instead.
• The same URL with a : in the query or fragment (?expires=12:00, #ref:main) fails on every platform with Refusing to install package with invalid name "<url>".
• Cause: ExtractTarball::name_and_basename (src/install/extract_tarball.rs:201) derives the label for the extraction temp directory from the placeholder name, which for bun add <url> is the URL itself. It takes bun_paths::basename(url) and strips .tgz, so the query string and fragment stay in the label. ? is not a legal NTFS file name character, so mkdir fails in extract(); is_safe_install_folder_name (src/install/dependency.rs:561) rejects a : in the label, and since the placeholder is a remote tarball both callers (extract() and TarballStream::open_destination) report that as an invalid package name.

Fix

• Cut the URL at the first ? or # before taking its basename, so the label is pkg-1.0.0 for both URLs above.
• If the label is still not a usable folder name (for example a URL with no path, where the basename is host:port), use package instead of failing. The validation the callers do is meant for dependency aliases, and a name starting with http(s):// is never an alias: it is the placeholder bun add <url> uses until the tarball's package.json is read, and the label is only used to name the temp directory. The cache folder is named after a hash of the URL (cached_tarball_folder_name_print) and is unaffected.
• name_and_basename is shared by the buffered extractor and the streaming one, so both paths are fixed by the same change. Aliased dependencies ("foo": "http://...") and npm packages do not take the changed branch and still go through the existing validation.
• Verified with the new cases in test/cli/install/bun-add.test.ts (?token=abc, ?expires=12:00, #ref:main, and /?file=... on a URL with no path for the package fallback, each through the buffered and the streaming extractor; the streaming cases assert the extractor's verbose Streamed line so both paths are known to be exercised):
  • Linux, without the fix: the 4 colon cases fail with Refusing to install package with invalid name; with the fix all 8 pass.
  • Windows x64, without the fix: the ?token=abc and /?file=... cases fail with the ENOENT errors above; the colon cases pass there only because the Windows branch of this function already cut the label at the last :. With the fix all 8 pass there as well.
  • The rest of bun-add.test.ts and bun-install-streaming-extract.test.ts pass with the fix.

Background

• Tarball extraction: a downloaded tarball is extracted into a fresh directory inside bun's temp directory and then renamed into the install cache. FileSystem::tmpname names that directory .<random>-<counter>.<label>; the label exists only to make leftover temp directories recognizable.
• Placeholder names: until a URL tarball has been extracted, bun does not know the package's name, so the dependency created by bun add <url> is named after the URL literal (PackageManagerResolution swaps in the real name afterwards). A dependency declared in package.json as "foo": "http://..." is named foo instead.
• is_safe_install_folder_name: the check applied to dependency names before they are used as directory names (rejects empty, ., .., \, : and NUL). The hardening rounds (Hardening: input validation and bounds tightening across 27 subsystems (round 6) #31417, Hardening: input validation and protocol tightening across 24 subsystems (round 7) #31495) made extraction refuse npm and remote tarball packages whose name fails it, so an untrusted alias cannot pick the directory; git and local tarball packages fall back to the label package there.
• Buffered vs streaming extraction: small responses are downloaded in full and extracted by ExtractTarball::extract; responses of at least BUN_INSTALL_STREAMING_MIN_SIZE (2 MiB by default) that arrive in several reads are extracted while downloading by TarballStream. Both call name_and_basename to pick the temp directory name; with --verbose the streaming path prints a Streamed ... tarball line, which the tests use to tell them apart.

[robobun]

Status: ready for review (head 5fef7c3).

Reproduced with the new cases in test/cli/install/bun-add.test.ts ("should add a tarball URL with a query string or fragment", 4 URL shapes, each through the buffered and the streaming extractor):

• Linux, unfixed build: the ?expires=12:00 and #ref:main cases fail with Refusing to install package with invalid name; the other two pass there because ? is a legal file name character on POSIX.
• Windows x64 (1.4.0 canary), unfixed build: the ?token=abc and /?file=... cases fail with ENOENT when create temporary directory named ".…-1.qs-pkg-1.0.0.tgz?token=abc" (buffered) and ENOENT extracting tarball for "<url>" (streaming); the colon cases pass there because the Windows branch of this function already cut the label at the last :.
• With the fix all 8 cases pass on Linux and on Windows x64 (debug builds of this branch); the rest of bun-add.test.ts and bun-install-streaming-extract.test.ts pass on Linux.

CI (build 97995): all 177 jobs that ran passed, including every Windows 2019 x64 and Windows 11 aarch64 test shard. The build is marked failed only because the two macOS 14 aarch64 test jobs expired without an agent picking them up, which is currently happening to every build in the pipeline; the annotated test failures (bun-audit, metafile, inspect-error-leak, test-crypto-dh-leak, ctrl-c, node-gyp EBUSY on Windows aarch64) all passed on retry and are unrelated to this change. Not retriggering until macOS agents are back.

[coderabbitai]

Walkthrough

Changes

The tarball installer now removes URL query and fragment suffixes before deriving extraction folder names. Unsafe URL-derived names use package. Tests cover buffered and streaming downloads.

Tarball URL basename handling

Layer / File(s)	Summary
URL and non-URL basename derivation src/install/extract_tarball.rs	URL-derived basenames strip query and fragment suffixes, remove archive extensions, and use package when unsafe. Non-URL basename handling remains unchanged.
Buffered and streaming URL coverage test/cli/install/bun-add.test.ts	Tests cover query strings, fragments, colon-containing suffixes, buffered extraction, streaming extraction, and successful dependency installation.

Possibly related PRs

• oven-sh/bun#37590: Handles related tarball dependency metadata and installation path behavior.
• oven-sh/bun#37669: Modifies related tarball extraction and streaming safety behavior.

Suggested reviewers: jarred-sumner

🚥 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 to tarball URL extraction folder names.
Description check	✅ Passed	The description explains the problem, fix, scope, and verification, although it does not use the template headings exactly.

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[coderabbitai]

Actionable comments posted: 1

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Inline comments:
In `@test/cli/install/bun-add.test.ts`:
- Around line 2677-2681: The suffix test cases in bun-add.test.ts do not cover
an unsafe archive basename. Add a case using a URL path such as /:.tgz and
assert that bun add succeeds, exercising the package fallback in the tarball
extraction path while preserving the existing suffix coverage.

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Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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📥 Commits

Reviewing files that changed from the base of the PR and between 732491c and 000adcc.

📒 Files selected for processing (2)

• src/install/extract_tarball.rs
• test/cli/install/bun-add.test.ts

[robobun]

^{Updated 4:45 AM PT - Aug 15th, 2026}

@robobun, your commit 5fef7c3 is building: #97995

[claude]

LGTM — the b"package" fallback coverage I flagged earlier is now exercised by the "query string on a URL without a path" case, and the comment-cop note was addressed in 5fef7c3.

What was reviewed:

• name_and_basename restructure: URL branch cuts at ?/#, strips archive extensions, falls back to b"package" when unsafe; non-URL branch (scoped names, Windows : strip) unchanged.
• Confirmed both callers (extract() and TarballStream::open_destination) still re-validate the truncated basename, so the alias path-traversal guard from #31417/#31495 is intact for non-URL names.
• Checked basename uses in move_to_cache_directory (create_subdir, index creation) — behavior unchanged for URL placeholders since is_safe_install_folder_name(name) was already false for full URLs.
• 8 test cases (4 URL shapes × buffered/streaming) with the Streamed marker asserting each mode took its own path.

Extended reasoning...

Overview

The PR fixes bun add <tarball-url> when the URL has a query string or fragment. ExtractTarball::name_and_basename (src/install/extract_tarball.rs:189) previously took bun_paths::basename(url) of the whole URL and stripped .tgz, leaving ?token=abc or #ref:main in the temp-directory label. On Windows ? is not a legal filename character (mkdir → ENOENT); on all platforms a : in the truncated label fails is_safe_install_folder_name and reports "Refusing to install package with invalid name". The fix restructures the function so URL-prefixed names are cut at the first ?/# before basename, and fall back to b"package" if the result still isn't a safe folder name. Non-URL names (npm packages, aliased dependencies) go through the unchanged else branch.

Security risks

None. The label is only used as the suffix of a random temp-directory name (FileSystem::tmpname); the cache folder for remote tarballs comes from cached_tarball_folder_name_print (a hash of the URL), not from this basename. The is_safe_install_folder_name gate that #31417/#31495 added to block path-traversal via dependency aliases is preserved: both callers still re-check the truncated basename, and the non-URL branch (which handles user-chosen aliases) is unchanged. The new b"package" fallback only applies to names that literally start with http:// or https://, which are the placeholders bun add <url> synthesizes — never a user-chosen alias.

Level of scrutiny

Medium. This is package-manager extraction code that touches directory naming, so I traced every downstream use of basename in move_to_cache_directory (the create_subdir heuristic and the per-version index symlink) to confirm URL placeholders behave as before — they do, because is_safe_install_folder_name(name) was already false for full URLs, so the index branch was and remains skipped. The Windows-only : strip moving into the else branch is safe because the URL branch now handles : via the fallback.

Other factors

• My earlier review flagged that the b"package" fallback had no test; e40f560 added the /?file=... case whose post-cut basename is 127.0.0.1:PORT (contains :), which reaches the fallback on every platform. The comment-cop bot's paragraph-comment note was addressed in 5fef7c3 (one line remains).
• Tests cover the full variant matrix per REVIEW.md: 4 URL shapes × buffered/streaming, with an explicit Streamed marker assertion so each mode is known to take its own extraction path. Fail-before/pass-after was verified on Linux and Windows x64 per the PR description.
• The fix is at the shared helper, so both extraction paths are covered by one change; aliased dependencies and npm packages don't take the changed branch.