fix(bootstrap): always try only-system fallback (drop too-strict gate, refs #130)

[debpalash]

Follow-up from verifying #140 by driving the real uv binary.

Finding: system_python_ge_311() was stricter than uv's own interpreter discovery — it probed only python3/python. On this Mac, python3 is the system 3.9.6 (no python), so the gate returned false and the only-system fallback was skipped — even though UV_PYTHON_PREFERENCE=only-system uv venv immediately resolves the Homebrew CPython 3.14.5. So in the exact worst case the fallback exists for (GitHub and mirror blocked), a user with a perfectly good system Python could be sent to the remediation screen.

Fix: drop the pre-gate (and the now-unused parse_py_version/system_python_ge_311 helpers + the parse test); always add the system-python attempt as the last cascade step. uv's discovery is the authority — with requires-python = ">=3.11" it resolves any compatible system interpreter (3.12/3.13/3.14…) or fails fast → remediation.

Verified live (real uv 0.11.14): only-system uv venv built a venv from system CPython 3.14.5 on a host with no 3.11.x. cargo test + cargo check clean.

Refs #130.

🤖 Generated with Claude Code

Summary by CodeRabbit

• Refactor
  • Improved bootstrap virtual environment creation with more reliable system Python fallback strategy. The setup process now consistently attempts system Python as a final option, leveraging built-in dependency version constraints for compatibility validation instead of pre-checks.

[coderabbitai]

Caution

Review failed

Pull request was closed or merged during review

📝 Walkthrough

Walkthrough

The PR simplifies venv bootstrap by removing pre-flight Python version checking and unconditionally adding a system-python fallback strategy that uses uv venv with system-only interpreter discovery. Version compatibility is delegated to uv and project constraints instead of shell-based pre-checks.

Changes

Bootstrap System Python Fallback Simplification

Layer / File(s)	Summary
Version pre-check helper removal frontend/src-tauri/src/bootstrap.rs	Functions parse_py_version and system_python_ge_311 that performed shell-based pre-flight Python >= 3.11 detection are removed, along with their unit test covering version string parsing.
Unconditional system-python fallback strategy frontend/src-tauri/src/bootstrap.rs	Bootstrap strategy selection now unconditionally appends a final uv venv attempt configured with UV_PYTHON_PREFERENCE=only-system, delegating version compatibility checks to uv interpreter discovery and the project's requires-python constraints instead of pre-checking on PATH.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The PR description provides a comprehensive explanation of the problem, the fix, and verification, but the template structure with Summary/Changes/Type/Testing/Checklist sections is not followed.	Reorganize the description to match the template: add a structured Summary section, list Changes as bullet points, check the appropriate Type checkbox (🐛 Bug fix applies here), document Testing steps, and complete the Checklist items.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately describes the main change: removing a strict gate and always attempting the system-python fallback, which aligns with the changeset that removes helper functions and unconditionally adds the fallback strategy.
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.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/bootstrap-only-system-fallback

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[greptile-apps]

Greptile Summary

This PR removes the system_python_ge_311 pre-gate (and its parse_py_version helper and associated test) from the ensure_venv_ready bootstrap cascade, replacing the conditional push with an unconditional one so the UV_PYTHON_PREFERENCE=only-system fallback is always attempted as the last resort.

• Drops parse_py_version and system_python_ge_311 helper functions along with the parse_py_version_handles_real_and_garbage unit test — the helpers were the only callers, so no dead code remains.
• The system-python venv attempt is now always appended to venv_attempts, delegating interpreter compatibility checks to uv's own discovery (governed by requires-python = \">=3.11\" in the project manifest) rather than a hand-rolled python3/python probe that missed Homebrew-managed interpreters.

Confidence Score: 4/5

The change is safe to merge — it strictly expands coverage by removing an overly conservative gate, and the worst-case outcome of the new path is the same remediation screen the gate would have shown.

The logic change is small and well-reasoned: delegating interpreter discovery to uv is clearly more reliable than the hand-rolled python3/python probe. The only leftover is a stale comment fragment referencing the removed condition, which has no runtime impact. The deleted test covered only the deleted helpers, so test coverage of remaining code is unaffected.

Only one file changed. The stale '(only if >= 3.11)' fragment in the step-by-step comment on line 454 is worth cleaning up before merging.

Important Files Changed

Filename	Overview
frontend/src-tauri/src/bootstrap.rs	Removes system_python_ge_311 pre-gate and parse_py_version helpers; always appends the UV_PYTHON_PREFERENCE=only-system venv attempt as a final fallback. One stale comment still references the old '(only if >= 3.11)' condition.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    A[ensure_venv_ready] --> B[resolve_uv]
    B --> C{uv available?}
    C -- No --> Z[fail → remediation]
    C -- Yes --> D[Attempt 1: uv venv --python 3.11 --managed-python\ndefault GitHub host]
    D -- success --> OK[venv_ok = true → proceed to uv sync]
    D -- fail --> E[Attempt 2: uv venv --python 3.11 --managed-python\nUV_PYTHON_INSTALL_MIRROR=gh-proxy]
    E -- success --> OK
    E -- fail --> F[Attempt 3: uv venv\nUV_PYTHON_PREFERENCE=only-system\nalways added — no pre-gate]
    F -- success --> OK
    F -- fail --> Z
    OK --> G[uv sync --frozen --no-dev]
    G -- success --> H[Return venv_python path]
    G -- fail --> Z

Loading

Comments Outside Diff (1)

1. frontend/src-tauri/src/bootstrap.rs, line 451-454 (link)

   The parenthetical (only if >= 3.11) is a leftover from the removed system_python_ge_311 gate and now describes behavior that no longer exists — the fallback is always added unconditionally.

   Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!

   

_{Reviews (1): Last reviewed commit: "fix(bootstrap): always try only-system f..." | Re-trigger Greptile}