Debugging Rails under ASDF in VSCode

Question

I'm trying to set a breakpoint in a Rails application from VSCode on a Mac. I'm using ASDF to install Ruby etc.

The default launch configuration in VSCode for Rails looks like this:

{
    "name": "Rails server",
    "type": "Ruby",
    "request": "launch",
    "program": "${workspaceRoot}/bin/rails",
    "args": [
        "server"
    ]
}

That fails because my which rails is Users/timregan/.asdf/shims/rails. But if I replace "program": "${workspaceRoot}/bin/rails" in the launch.json with "program": "/Users/timregan/.asdf/shims/rails" I get this error message when I try to launch a debugging session:

    Uncaught exception: /Users/timregan/.asdf/shims/rails:3: unknown regexp options - hbrw
    exec /opt/homebrew/opt/asdf/libexec/bin/asdf ex...
            ^~~~~~~~~
    /Users/timregan/.asdf/shims/rails:3: syntax error, unexpected local variable or method, expecting `do' or '{' or '('
    .../opt/asdf/libexec/bin/asdf exec "rails" "$@"
    ...                           ^~~~

        /Users/timregan/.asdf/installs/ruby/3.0.3/bin/rdebug-ide:25:in `load'
        /Users/timregan/.asdf/installs/ruby/3.0.3/bin/rdebug-ide:25:in `'

What is the correct setting to use in VSCode's launch.json to debug Rails when using ASDF?

Answer 1

This is due to ruby interpreting the . in .asdf or user.name as a regular expression and messing up the paths.

What solved it, was adding binstubs to wrap the real path of the executable (.../.asdf/.../rspec) with a {workspaceFolder}/bin/rspec

bundle binstubs bundler ruby-debug-ide solargraph rspec-core

and the binstubs to reference the shimed executables:

      "program": "${workspaceFolder}/bin/rspec",
      "pathToRDebugIDE": "/${workspaceFolder}/bin/rdebug-ide",
      "pathToBundler": "${workspaceFolder}/bin/bundle",

---

Source: Found the solution in this article where you get a step-by-step on setting up your project + launch.json:

https://dev.to/abstractart/easy-way-to-setup-debugger-and-autocomplete-for-ruby-in-visual-studio-code-2gcc

Big kudos to the author