fix(activate): don't reorder PATH for the mise dir in --shims mode

[JamBalaya56562]

Problem

On a deb/rpm install (mise at /usr/bin/mise), mise activate bash --shims emits:

export PATH="/usr/bin:$PATH"
export PATH="/home/viktor/.local/share/mise/shims:$PATH"

The first line duplicates /usr/bin and moves it ahead of /usr/local/bin, changing command resolution — locally/admin-installed binaries in /usr/local/bin no longer take precedence. Reported in #10264.

Root cause

activate_shims() prepends both the shims dir and the directory containing the mise executable. PR #8757 made --shims activation always prepend (dropping the "already in PATH" guard) so the shims dir reliably moves to the front when shell config is re-sourced (e.g. VS Code terminals). But activate_shims() routes both the shims dir and the mise exe dir through that same unconditional helper, so the exe dir lost the guard too. For a deb install the exe dir is /usr/bin, which is already in PATH — so it gets re-prepended and reordered.

Fix

Keep always-prepending the shims dir (preserving #8757''s re-source behavior), but emit the mise executable''s own dir through the guarded prepend_path, which skips directories already in PATH. The exe dir only needs to be present so mise is callable — never at the front.

For a deb install, activation now emits only:

export PATH="$HOME/.local/share/mise/shims:$PATH"

and never reorders existing PATH entries.

Testing

• Extended e2e/shell/test_shims_activate_prepend: when the mise executable''s dir is already in PATH, exactly one export PATH= line (the shims dir) is emitted — the exe dir is not re-prepended. The existing assertions (shims dir is always prepended, with or without it already in PATH) still hold.
• cargo fmt --all -- --check passes.

Addresses #10264

🤖 Generated with Claude Code

Summary by CodeRabbit

• Bug Fixes

  • Prevented shim activation from reordering PATH when the tool's install directory is already present, avoiding redundant PATH modifications.

• Tests

  • Added a regression test to confirm activation emits a single PATH export and does not re-prepend an existing install directory.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 0f950f3c-53c4-4130-abbe-0161ca94259f

📥 Commits

Reviewing files that changed from the base of the PR and between efbe835 and 5498a86.

📒 Files selected for processing (2)

• e2e/shell/test_shims_activate_prepend
• src/cli/activate.rs

🚧 Files skipped from review as they are similar to previous changes (2)

• e2e/shell/test_shims_activate_prepend
• src/cli/activate.rs

---

📝 Walkthrough

Walkthrough

Switches shims activation to use guarded prepend_path(exe_dir) (avoiding re-prepend/reorder of an already-present exe_dir) and adds an e2e test verifying activation emits a single PATH export that begins with SHIMS_DIR when exe_dir is already in PATH.

Changes

Executable Directory Prepend Fix

Layer / File(s)	Summary
Guarded prepend logic for executable directory src/cli/activate.rs	activate_shims now calls prepend_path(exe_dir) instead of shims_prepend_path(shell, exe_dir), so exe_dir is only emitted when allowed by guards; doc comment for shims_prepend_path updated to clarify shim-specific behavior.
Regression test for executable directory prepend e2e/shell/test_shims_activate_prepend	Adds a test that sets PATH including EXE_DIR, runs mise activate bash --shims, asserts the exported PATH begins with SHIMS_DIR, and verifies exactly one export PATH= line is produced.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Poem

A rabbit hops through PATH so fleet,
It checks the trail with nimble feet,
If exe is found, it will not shove—
Shims lead the dance, one path above. 🐰

🚥 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 directly and clearly summarizes the main fix: preventing PATH reordering for the mise directory in --shims mode, which is the core change across both modified files.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
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.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

---

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

[greptile-apps]

Greptile Summary

This PR fixes a PATH reordering bug in --shims activation mode where the directory containing the mise binary (e.g. /usr/bin on deb/rpm installs) was unconditionally prepended to PATH on every re-source, moving it ahead of entries like /usr/local/bin. The fix routes the mise executable's directory through the guarded prepend_path() (which skips directories already present in PATH) while keeping the shims directory on the unconditional shims_prepend_path() path so it reliably stays at the front on re-source.

• src/cli/activate.rs: activate_shims() now calls self.prepend_path(exe_dir) instead of self.shims_prepend_path(shell, exe_dir), adding an is_dir_in_path guard for the executable directory without affecting the shims dir behaviour.
• e2e/shell/test_shims_activate_prepend: Adds a regression test that pre-populates PATH with EXE_DIR and asserts only one export PATH= line (the shims dir) is emitted.

Confidence Score: 5/5

Safe to merge — the change is a one-line switch to an already-present guarded helper with a targeted regression test covering the fixed scenario.

The diff is minimal: one call-site change in activate_shims() and a new e2e test case. The guarded prepend_path() it switches to was already used by the non-shims activate() path and is well understood. The regression test directly exercises the fixed case and correctly uses the existing assert_contains_text harness helper. No logic around the shims directory itself is touched.

No files require special attention.

Important Files Changed

Filename	Overview
src/cli/activate.rs	Switches activate_shims() to use the guarded prepend_path() for exe_dir instead of the always-prepend shims_prepend_path(); the shims dir keeps its unconditional prepend via shims_prepend_path(). Change is minimal and correctly scoped.
e2e/shell/test_shims_activate_prepend	Adds a regression test that sets PATH to include EXE_DIR before activation, then asserts exactly one export PATH= line is emitted (the shims dir); correctly uses the existing assert_contains_text helper.

_{Reviews (2): Last reviewed commit: "fix(activate): don't reorder PATH for th..." | Re-trigger Greptile}

[greptile-apps]

Fish: exe_dir switches from MovePrependEnv to PrependEnv

Before this PR, activate_shims() called shims_prepend_path(shell, exe_dir), which emitted MovePrependEnv for fish (using fish's native path dedup so re-sourcing is idempotent). The new prepend_path(exe_dir) always emits PrependEnv regardless of shell. For fish users where exe_dir is not already in PATH (e.g. a custom ~/.local/bin install), re-sourcing the config after a system-level rc resets PATH could duplicate exe_dir, because PrependEnv is not natively idempotent under fish. The guard !is_dir_in_path makes this safe for the common re-source case, but it breaks in the "PATH reset between sources" scenario that MovePrependEnv handles natively. Consider emitting MovePrependEnv(exe_dir) when shell.supports_move_path() is true, falling back to the guarded PrependEnv otherwise.

[JamBalaya56562]

Thanks, but I don''t think this one applies here. On fish, PrependEnv renders as fish_add_path --global --path (src/shell/fish.rs), and fish_add_path is idempotent — it won''t add a path that''s already present, so re-sourcing (even after a PATH reset) doesn''t duplicate exe_dir. The only behavioural difference vs MovePrependEnv (fish_add_path --move) is whether an already-present entry gets moved to the front.

Moving it is exactly what this PR is fixing: for a deb install exe_dir is /usr/bin, which is already in PATH, so MovePrependEnv would move /usr/bin ahead of /usr/local/bin — reintroducing #10264 on fish. The guarded prepend_path leaves an already-present exe_dir untouched on every shell (and fish_add_path --path adds it idempotently when it is genuinely missing), matching what the non-shims activate() path already does for exe_dir. So I''m keeping prepend_path here.

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@e2e/shell/test_shims_activate_prepend`:
- Around line 23-29: The test currently masks failures by appending "|| true" to
the activation command that sets out, so replace that pattern: run the
activation command capturing its stdout/stderr into out (keep env
PATH="$EXE_DIR:..." "$MISE_BIN" activate bash --shims 2>&1), then immediately
check the command's exit status and fail the test if it's non-zero (print out
the captured out for diagnostics and exit non‑zero) before continuing with
assert_contains_text and the path_lines checks; this removes the "|| true"
suppression while preserving captured output for assertions.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

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

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 4d9745a8-d5bf-4ba3-989b-458787537dae

📥 Commits

Reviewing files that changed from the base of the PR and between e420ad4 and 46296bd.

📒 Files selected for processing (2)

• e2e/shell/test_shims_activate_prepend
• src/cli/activate.rs