Elixir-LS V0.30.0: Troubleshooting ASDF_DIR And ASDF_DATA_DIR

by Alex Johnson 62 views

Are you struggling to get Elixir-LS v0.30.0 working with your ASDF-managed Elixir installation? You're not alone! Many developers have encountered issues where the extension fails to detect the Elixir installation unless specific environment variables are set. This article dives deep into this problem, offering solutions and insights to help you get your Elixir Language Server up and running smoothly.

The Issue: Elixir-LS Not Detecting ASDF Elixir

Many users, particularly those on Arch Linux or similar systems using ASDF for managing Elixir and Erlang versions, have reported that Elixir-LS v0.30.0 doesn't work out of the box. Even with Elixir and Erlang properly installed and configured through ASDF, the Language Server Protocol (LSP) client in VS Code or other editors may fail to recognize the Elixir installation.

The core problem lies in how Elixir-LS discovers the Elixir executable. The extension needs to know where to find the elixir binary to provide features like autocompletion, go-to-definition, and diagnostics. When using ASDF, Elixir is installed in a specific directory managed by ASDF, which isn't always in the system's default $PATH.

This can be incredibly frustrating, especially after spending hours trying different configurations. You might encounter errors in your LSP client, or simply notice that Elixir-LS features aren't working as expected. Let's explore the solution that often resolves this issue: setting ASDF_DIR and ASDF_DATA_DIR.

The Solution: Setting ASDF_DIR and ASDF_DATA_DIR

The key to resolving this issue often involves explicitly setting the ASDF_DIR and ASDF_DATA_DIR environment variables. These variables tell Elixir-LS (and other tools that integrate with ASDF) where to find the ASDF installation and its data directory.

  • ASDF_DIR: This variable points to the directory where ASDF is installed itself. This is usually in your home directory, often at $HOME/.asdf. However, if you've installed ASDF in a different location, you'll need to adjust this accordingly.
  • ASDF_DATA_DIR: This variable specifies the directory where ASDF stores its data, including the installed versions of Elixir, Erlang, and other tools. By default, this is often set to $HOME/.asdf/installs, but can be customized.

The original reporter of this issue found that setting ASDF_DATA_DIR was the critical step in getting Elixir-LS to recognize their ASDF-installed Elixir. While the script might not explicitly read ASDF_DIR for versions greater than 0.16, setting both variables is a good practice to ensure compatibility and avoid future issues.

How to Set These Variables

There are several ways to set these environment variables, depending on your operating system and development environment:

  1. Globally in your shell: You can add the following lines to your shell's configuration file (e.g., .bashrc, .zshrc):

    export ASDF_DIR="$HOME/.asdf"
export ASDF_DATA_DIR="$HOME/.asdf/installs"

    After adding these lines, you'll need to restart your terminal or source the configuration file (e.g., source ~/.zshrc) for the changes to take effect.

  2. In your VS Code settings: You can set environment variables specifically for VS Code. This is often the preferred method, as it isolates the variables to your development environment. To do this:

    • Open VS Code settings (File > Preferences > Settings).

    • Search for "environment variables".

    • Click "Edit in settings.json".

    • Add the following to your settings.json file:

      "terminal.integrated.env.linux": {
    "ASDF_DIR": "$HOME/.asdf",
    "ASDF_DATA_DIR": "$HOME/.asdf/installs"
},
"terminal.integrated.env.osx": { // for macOS
    "ASDF_DIR": "$HOME/.asdf",
    "ASDF_DATA_DIR": "$HOME/.asdf/installs"
},
"terminal.integrated.env.windows": { // for Windows
    "ASDF_DIR": "%USERPROFILE%/.asdf",
    "ASDF_DATA_DIR": "%USERPROFILE%/.asdf/installs"
}

    • Adjust the paths if your ASDF installation is in a different location. You may need to adjust the OS key, such as linux, osx, and windows.

  3. In your project's .env file (if using a library like dotenv): If you're using a library like dotenv to manage environment variables for your project, you can add these variables to your .env file.

After setting these variables, restart VS Code or your LSP client to ensure the changes are applied.

Why This Works: How Elixir-LS Finds Elixir

Elixir-LS likely relies on ASDF's shims or its own mechanisms to locate the Elixir executable. ASDF uses shims, which are small executable files placed in your $PATH. When you run elixir, you're actually running the shim, which then figures out the correct Elixir version to use based on your project's configuration or the global ASDF configuration.

By setting ASDF_DIR and ASDF_DATA_DIR, you're providing Elixir-LS with the necessary information to correctly locate ASDF and its shims, allowing it to find the Elixir executable.

Troubleshooting Tips

If setting ASDF_DIR and ASDF_DATA_DIR doesn't immediately solve the issue, here are some additional troubleshooting steps:

  • Verify ASDF Installation: Ensure that ASDF is correctly installed and configured. You can check this by running asdf --version in your terminal. If ASDF is not found, you may need to add ASDF's shims directory to your $PATH.
  • Check Elixir Installation: Verify that Elixir is installed through ASDF by running asdf list elixir. This should show you the installed Elixir versions.
  • Inspect Elixir-LS Logs: Many LSP clients provide logs that can help diagnose issues. Check the Elixir-LS logs for any error messages related to finding Elixir or ASDF.
  • Restart LSP Client: Sometimes, restarting your LSP client (e.g., restarting VS Code) can resolve issues related to environment variable changes.
  • Check for Conflicting Elixir Installations: If you have Elixir installed through other means (e.g., your system's package manager), it might be conflicting with the ASDF installation. Ensure that ASDF's shims are prioritized in your $PATH.

Contributing to the Documentation

The original user who reported this issue suggested adding this troubleshooting information to the Elixir-LS README. This is an excellent idea, as it can save other developers from experiencing the same frustration. If you've encountered this issue and found a solution, consider contributing a pull request to the Elixir-LS documentation. Sharing your knowledge can help the entire Elixir community.

Conclusion

Getting Elixir-LS to work seamlessly with ASDF can sometimes be tricky, but by understanding the role of ASDF_DIR and ASDF_DATA_DIR, you can often resolve the issue. Remember to set these variables correctly in your environment, and don't hesitate to consult the troubleshooting tips if you encounter further problems. By working together and sharing our experiences, we can make Elixir development smoother and more enjoyable for everyone.

For more information about Elixir and related tools, you can visit the official Elixir website. This resource provides comprehensive documentation, guides, and community resources to help you learn and master Elixir development.