Fix 'latest' version resolution and zls error handling for asdf-vm/actions v4

[Copilot]

PR #21 upgrades asdf-vm/actions from v3 to v4, which exposed two issues in the plugin:

1. Ubuntu tests fail with "There is no such version: latest"
2. macOS tests fail when zigtools.org API returns HTTP 500

Changes

• lib/utils.py: Resolve 'latest' to actual version number before lookup

  if version == 'latest':
      versions = list(k for k in index.keys() if k != 'master')
      versions.sort(key=lambda v: tuple(map(int, v.split('.'))))
      version = versions[-1]

• lib/utils.py: Wrap optional zls download in try-except to prevent installation failures

• .gitignore: Exclude Python cache files

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• ziglang.org
  • Triggering command: /usr/bin/python3 python3 lib/utils.py latest-version (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

Pull request: #21

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[Copilot]

Pull request overview

This PR addresses two issues exposed by the asdf-vm/actions v4 upgrade: handling of the 'latest' version string and preventing installation failures when the zls download service is unavailable.

Changes:

• Added logic to resolve 'latest' version string to an actual version number before lookup
• Added error handling to make zls download optional, preventing installation failures
• Added Python cache files to .gitignore

Reviewed changes

Copilot reviewed 1 out of 2 changed files in this pull request and generated 3 comments.

File	Description
lib/utils.py	Added 'latest' version resolution logic and wrapped zls download in try-except for graceful failure handling
.gitignore	Added Python bytecode cache exclusions (*.pyc and pycache/)

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[Copilot]

The version sorting logic will fail if any version string contains non-numeric components (e.g., "0.11.0-dev.1234+abc"). The map(int, v.split('.')) will raise a ValueError when trying to convert non-numeric strings to integers. This logic is duplicated from the all_versions() function at line 83, which has the same issue. Consider using a more robust version parsing approach or catching and handling malformed version strings appropriately.

[Copilot]

This version resolution logic duplicates the functionality already present in the all_versions() function (lines 80-84). Consider refactoring to call all_versions() directly and return the last element, which would reduce code duplication and ensure consistency.

[Copilot]

The broad exception handler catches all exceptions, including programming errors like AttributeError, NameError, or KeyboardInterrupt. Consider catching more specific exceptions (e.g., HTTPAccessError, HTTPError, URLError) to avoid silently suppressing unexpected errors that should be addressed.