Python resolution order does not respect PATH

[VRehnberg]

I've searched open issues for similar requests

• Yes

I've manually reviewed logs to find potential errors

• Yes

I've recently downloaded the latest plugin version of mason.nvim

• Yes

Problem description

From a conda environment with Python 3.9.17 (picked up by :checkhealth mason) pypi installer picks up and uses system python version 3.10. Output from MasonLog:

[INFO  ons  3 jul 2024 11:11:01] ...e/nvim/lazy/mason.nvim/lua/mason-core/installer/init.lua:184: Executing installer for Package(name=ruff-lsp) {}
[ERROR ons  3 jul 2024 11:11:01] ...e/nvim/lazy/mason.nvim/lua/mason-core/installer/init.lua:249: Installation failed for Package(name=ruff-lsp) error=spawn: python3.10 failed with exit code 1 and signal 0. 

Expected behavior

PATH should be respected. It looks like the culprit is [resolve_python3](https://github.com/williamboman/mason.nvim/blob/main/lua/mason-core/installer/managers/pypi.lua#L20-L33)() and probably the call for versioned candidates at https://github.com/williamboman/mason.nvim/blob/main/lua/mason-core/installer/managers/pypi.lua#L91

Instead of taking the python resolved by PATH it picks the latest python version that is supported.

Steps to reproduce

1. Create a conda virtual environment with a supported Python version older than the system one
2. Set PATH="append" (or "skip"):

{
    "williamboman/mason.nvim",
    config = function()
      require('mason').setup({
        PATH = "append",
      })
    end
}

3. Open python file with Neovim (might need some python lsp neovim package as well, not sure what is telling mason to install ruff-lsp)

Affected packages

ruff-lsp

Neovim version (>= 0.7)

NVIM v0.10.0
Build type: RelWithDebInfo
LuaJIT 2.1.1713484068

Operating system/version

Linux c3se-TP6 6.5.0-41-generic #41~22.04.2-Ubuntu SMP PREEMPT_DYNAMIC Mon Jun 3 11:32:55 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

Healthcheck

==============================================================================
mason: require("mason.health").check()

mason.nvim ~
- OK mason.nvim version v1.10.0
- OK PATH: append
- OK Providers: 
    mason.providers.registry-api
    mason.providers.client
- OK neovim version >= 0.7.0

mason.nvim [Registries] ~
- OK Registry `github.com/mason-org/mason-registry version: 2024-07-02-cyan-tub` is installed.

mason.nvim [Core utils] ~
- OK unzip: `UnZip 6.00 of 20 April 2009, by Debian. Original by Info-ZIP.`
- OK wget: `GNU Wget 1.21.2 built on linux-gnu.`
- OK curl: `curl 7.81.0 (x86_64-pc-linux-gnu) libcurl/7.81.0 OpenSSL/3.0.2 zlib/1.2.11 brotli/1.0.9 zstd/1.4.8 libidn2/2.3.2 libpsl/0.21.0 (+libidn2/2.3.2) libssh/0.9.6/openssl/zlib nghttp2/1.43.0 librtmp/2.3 OpenLDAP/2.5.17`
- OK gzip: `gzip 1.10`
- OK tar: `tar (GNU tar) 1.34`
- OK bash: `GNU bash, version 5.1.16(1)-release (x86_64-pc-linux-gnu)`
- OK sh: `Ok`

mason.nvim [Languages] ~
- WARNING Go: not available
  - ADVICE:
    - spawn: go failed with exit code - and signal -. go is not executable
- WARNING cargo: not available
  - ADVICE:
    - spawn: cargo failed with exit code - and signal -. cargo is not executable
- WARNING luarocks: not available
  - ADVICE:
    - spawn: luarocks failed with exit code - and signal -. luarocks is not executable
- WARNING Ruby: not available
  - ADVICE:
    - spawn: ruby failed with exit code - and signal -. ruby is not executable
- WARNING RubyGem: not available
  - ADVICE:
    - spawn: gem failed with exit code - and signal -. gem is not executable
- WARNING Composer: not available
  - ADVICE:
    - spawn: composer failed with exit code - and signal -. composer is not executable
- WARNING PHP: not available
  - ADVICE:
    - spawn: php failed with exit code - and signal -. php is not executable
- WARNING javac: not available
  - ADVICE:
    - spawn: javac failed with exit code - and signal -. javac is not executable
- WARNING java: not available
  - ADVICE:
    - spawn: java failed with exit code - and signal -. java is not executable
- WARNING julia: not available
  - ADVICE:
    - spawn: julia failed with exit code - and signal -. julia is not executable
- OK python: `Python 3.9.17`
- OK node: `v18.16.0`
- OK pip: `pip 24.0 from /home/vikren/miniconda3/envs/ds/lib/python3.9/site-packages/pip (python 3.9)`
- OK python venv: `Ok`
- OK npm: `9.5.1`

mason.nvim [GitHub] ~
- OK GitHub API rate limit. Used: 0. Remaining: 60. Limit: 60. Reset: ons  3 jul 2024 12:49:17.
  Install and authenticate via gh-cli to increase rate limit.

Screenshots or recordings

No response

[VRehnberg]

A quick fix for me was to modify https://github.com/williamboman/mason.nvim/blob/main/lua/mason-core/installer/managers/pypi.lua#L91:

-    local target = resolve_python3(versioned_candidates) or stock_target
+    local target = stock_target

[VRehnberg]

My suggested solution would be to just use stock_target and check if it is compatible. If isn't, throw an error and exit rather than trying to use a non-default python. (But, that could be a breaking change for those that rely on the old behaviour).

[williamboman]

Should be fixed in #1736. Note that it will only use the python3 executable in PATH if it satisfies the python version requirement (if specified by the package).