[jdx]

Summary

Extends the resolve_exact_version fast path introduced for cargo in #11013 to the npm, go, gem, pipx, and dotnet backends.

When a version request parses as full semver (versions::SemVer), resolution now skips fetching the remote version list entirely and defers authoritative validation to the underlying installer, which fails cleanly when the version doesn't exist upstream:

Backend	Installer validation
npm	npm/bun/pnpm/aube install pkg@version
go	go install mod@vX.Y.Z (validates against the module proxy; v-prefixed requests are normalized to match listed versions)
gem	gem install --version
pipx	pipx install pkg==version / uv tool install
dotnet	dotnet tool install --version

This mostly benefits flows the lockfile short-circuit doesn't cover: exact pins in mise.toml without a lockfile, first-time mise install tool@x.y.z, and mise x tool@x.y.z.

What still uses remote discovery

• Fuzzy/prefix/channel requests (latest, 3, 3.1, ^1.2.3, next)
• Non-semver version schemes, so prefix promotion keeps working where those schemes exist: RubyGems 4-part versions (5.0.0.1) and dotted prereleases (1.2.3.rc1), PEP 440 (1.2.3.post1, 1.2.3rc1, 1.2.3.4), legacy 4-part NuGet versions
• Git-sourced pipx tools (pipx:owner/repo, pipx:git+...) — versions there are repo tags, mirroring the cargo git_url escape hatch

Behavior tradeoff (same as #11013)

An exact 3-part pin that does not exist upstream now fails at install time with the installer's error, instead of being silently promoted to a separator-suffixed variant (1.2.3 → 1.2.3.4 / 1.2.3-rc1) during resolution. Explicit exact pins also stay outside release-age filtering, per the existing comment in tool_version.rs.

Verification

• 11 new unit tests mirroring the cargo ones (exact resolves, fuzzy/non-semver/git fall through) — all pass
• Traced end-to-end with a debug build: mise install --dry-run npm:cowsay@1.6.0 resolves with zero remote calls (no npm view), while the fuzzy control npm:cowsay@1.6 still fetches the version list and resolves to 1.6.0

---

This PR was generated by an AI coding assistant.

🤖 Generated with Claude Code

---

Note

Medium Risk
Changes version resolution behavior for exact pins across five install backends; wrong semver classification could skip needed remote discovery or change failure mode from resolution promotion to install-time errors.

Overview
Extends the resolve_exact_version fast path (from cargo) to npm, go, gem, pipx, and dotnet. When a pin parses as full semver via versions::SemVer, mise skips remote version-list fetches and treats the string as exact; missing versions surface at install time from the package manager instead of during resolution.

Backend-specific rules: go strips a leading v before semver checks; pipx only applies the fast path for PyPI tools (git-sourced tools still use remote discovery); gem, dotnet, and pipx leave non-semver schemes (RubyGems 4-part/dotted prereleases, NuGet 4-part, PEP 440) on the remote-discovery path so prefix promotion keeps working.

Tradeoff: exact semver pins that do not exist upstream no longer get silently promoted to separator-suffixed variants during resolution—they fail with the installer’s error instead.

Adds unit tests on each backend mirroring cargo (exact semver resolves, fuzzy/non-semver/git fall through).

^{Reviewed by Cursor Bugbot for commit c6fd9d2. Bugbot is set up for automated code reviews on this repo. Configure here.}

Summary by CodeRabbit

• New Features

  • Improved version resolution for .NET, RubyGems, Go, npm, and pipx packages.
  • Exact semantic versions, including supported prerelease versions and Go’s v prefix, can now resolve directly.
  • Non-semantic, partial, range-based, legacy, and Git-based version references continue through remote discovery for more accurate results.

• Tests

  • Added coverage for exact, fuzzy, legacy, prerelease, and unsupported version formats across supported package ecosystems.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Central YAML (base), Organization UI (inherited)

Review profile: CHILL

Plan: Pro Plus

Run ID: e294f17b-d961-4378-9935-60da5b6a8445

📥 Commits

Reviewing files that changed from the base of the PR and between 33440d6 and c6fd9d2.

📒 Files selected for processing (5)

• src/backend/dotnet.rs
• src/backend/gem.rs
• src/backend/go.rs
• src/backend/npm.rs
• src/backend/pipx.rs

---

📝 Walkthrough

Walkthrough

Five package backends now resolve exact SemVer inputs locally, while non-SemVer, fuzzy, range, legacy, and Git-based inputs return None for remote discovery. Async Tokio tests cover accepted and rejected version formats.

Changes

Exact version resolution

Layer / File(s)	Summary
Standard backend SemVer resolution src/backend/dotnet.rs, src/backend/gem.rs, src/backend/go.rs, src/backend/npm.rs	Dotnet, Gem, Go, and NPM validate exact versions as SemVer, with Go normalizing a leading v; tests cover valid, fuzzy, range, and legacy inputs.
PIPX target-specific resolution src/backend/pipx.rs	PIPX resolves SemVer versions locally for PyPI targets and returns None for non-SemVer values and Git-based specifications, with corresponding async tests.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Suggested reviewers: risu729

Poem

A rabbit hops through versions bright,
SemVer stars resolve just right.
Fuzzy tags take the distant trail,
Git winds tug a remote sail.
Tests thump softly: green and neat!

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly summarizes the main change: expanding exact-version fast paths to more backends and skipping remote discovery.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
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.

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}

[greptile-apps]

Greptile Summary

This PR extends the resolve_exact_version fast path (previously only on cargo) to the npm, go, gem, pipx, and dotnet backends. When a version string parses as full semver, mise now skips fetching the remote version list entirely and defers authoritative validation to the underlying installer; non-semver, fuzzy, and git-sourced version requests continue through normal remote discovery.

• Each backend correctly gates on versions::SemVer::new(version) to catch only strict 3-part versions; backend-specific non-semver schemes (NuGet 4-part, RubyGems dotted prerelease, PEP 440 extras) all fall through as intended, verified by the new unit tests.
• The go backend strips a leading v before the semver check and returns the bare version, matching how listed versions are stored; install_version_ already re-adds the v prefix before invoking go install, so there is no mismatch.
• The pipx backend deliberately calls get_registry_url() in the fast path to surface misconfigured index URLs at resolve time, consistent with what remote discovery does.

Confidence Score: 5/5

Safe to merge — the change is a narrowly-scoped fast path that only activates for full three-part semver strings; all other version patterns (fuzzy, prerelease scheme variants, git-sourced) continue through the existing remote-discovery code path.

Each backend's semver gate is correct and independently unit-tested. The go v-prefix normalization is consistent with how install_version_ later re-adds the prefix. The pipx git-source escape hatch is well-covered by tests. No correctness gap was found across all five backends.

No files require special attention; all five backends follow the same pattern and the unit tests are comprehensive.

Important Files Changed

Filename	Overview
src/backend/dotnet.rs	Adds resolve_exact_version fast path: full semver bypasses remote discovery; 4-part NuGet versions fall through correctly. Tests cover exact, fuzzy, and legacy formats.
src/backend/gem.rs	Adds resolve_exact_version fast path: 4-part (5.0.0.1) and dotted-prerelease (1.2.3.rc1) RubyGems versions correctly fall through; strict 3-part semver is treated as exact.
src/backend/go.rs	Adds resolve_exact_version fast path with v-prefix stripping; returned version without v matches how listed versions are stored and install_version_ re-adds the prefix before invoking go install.
src/backend/npm.rs	Adds resolve_exact_version fast path: strict semver (including prerelease like 1.1.0-beta.1) is treated as exact; dist-tags and range expressions fall through to remote discovery.
src/backend/pipx.rs	Adds resolve_exact_version fast path: git-sourced tools always fall through; PyPI tools validate registry URL config eagerly (intentional parity with remote-discovery behaviour) then skip fetch for strict semver versions.

_{Reviews (2): Last reviewed commit: "fix(backend): validate pipx registry url..." | Re-trigger Greptile}

[github-actions]

Hyperfine Performance

mise x -- echo

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
mise-2026.7.7 x -- echo	20.9 ± 1.1	18.6	26.5	1.01 ± 0.10
mise x -- echo	20.6 ± 1.8	18.3	46.9	1.00

mise env

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
mise-2026.7.7 env	20.5 ± 1.1	18.4	25.0	1.10 ± 0.08
mise env	18.7 ± 0.9	17.1	23.6	1.00

mise hook-env

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
mise-2026.7.7 hook-env	21.0 ± 1.0	19.0	24.7	1.07 ± 0.07
mise hook-env	19.6 ± 1.0	17.8	23.8	1.00

mise ls

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
mise-2026.7.7 ls	18.5 ± 1.0	16.7	23.1	1.06 ± 0.08
mise ls	17.5 ± 1.0	15.4	22.0	1.00

xtasks/test/perf

Command	mise-2026.7.7	mise	Variance
install (cached)	168ms	171ms	-1%
ls (cached)	64ms	59ms	+8%
bin-paths (cached)	63ms	61ms	+3%
task-ls (cached)	128ms	128ms	+0%

[coderabbitai]

Caution

Review failed

An error occurred during the review process. Please try again later.

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}