Support configuring custom rspec command in VS Code (#57)

* Add support configuring rspec command and relative path

* Fix command generation and type issues

* Add specs to exercise new configuration options

* Add documentation for new configuration items

* Add debug option and clarify preferred dev container strategy

This commit adds an option (consumed from VS Code settings) that
allows a debug mode to troubleshoot configuration issues.

Further, this commit clarifies the preferred approach for using
this addon with Dev Containers.

Projects that use Docker or other container technologies for development
should use a the VS Code Dev Containers extension to run Ruby LSP _within_
the dev Container.

This prevents situations where the spec paths provided to rspec are
host machine paths rather than container paths.

* Correct linting errors

README.md

@@ -56,6 +56,83 @@ In VS Code this feature can be triggered by one of the following methods:
 
 <img src="misc/go-to-definition.gif" alt="Go to definition" width="75%">
 
+### VS Code Configuration
+`ruby-lsp-rspec` supports various configuration items exposed via `settings.json` in VS Code.
+
+These configuration options require the `ruby-lsp` VS Code plugin are nested within `rubyLsp.addonSettings`:
+```json
+{
+  ...
+  "rubyLsp.addonSettings": {
+    "Ruby LSP RSpec": {
+      // Configuration goes here
+    }
+  }
+}
+```
+
+#### `rspecCommand`
+**Description:**
+Override the inferred rspec command with a user-specified command
+
+**Default Value**: `nil` (infer rspec command based on presence of a binstub or Gemfile)
+
+**Example**
+```json
+{
+  ...
+  "rubyLsp.addonSettings": {
+    "Ruby LSP RSpec": {
+      "rspecCommand": "rspec -f d",
+    }
+  }
+}
+```
+
+#### `debug`
+**Description:**
+A boolean flag that prints the complete RSpec command to stdout when enabled.
+
+View the output in VS Code's `OUTPUT` panel under `Ruby LSP`.
+
+**Default Value**: `false`
+
+**Example**
+```json
+{
+  ...
+  "rubyLsp.addonSettings": {
+    "Ruby LSP RSpec": {
+      "debug": true
+    }
+  }
+}
+```
+
+#### Developing on containers
+If your project uses containers for development, you should use `Visual Studio Code Dev Containers` extension.
+
+This extension will run Ruby LSP (and thus Ruby LSP RSpec) within the Dev Container, which allows the proper spec paths to be sent to rspec.
+
+For more details on using Ruby LSP with containers and setting up the dev continers extension, see [the Ruby LSP documentation](https://github.com/Shopify/ruby-lsp/blob/main/vscode/README.md?tab=readme-ov-file#developing-on-containers).
+
+Be sure to specify Ruby LSP as an extension that should run _within_ the Dev Container in your `.devcontainer.json`:
+```json
+{
+  "name": "my-app",
+  ...
+  "customizations": {
+    "vscode": {
+      "extensions": [
+        "Shopify.ruby-lsp"
+        ...
+      ]
+    }
+  }
+}
+```
+
+
 ## Development
 
 After checking out the repo, run `bin/setup` to install dependencies. Then, run `rake spec` to run the tests. You can also run `bin/console` for an interactive prompt that will allow you to experiment.

lib/ruby_lsp/ruby_lsp_rspec/addon.rb

@@ -14,9 +14,26 @@ module RSpec
     class Addon < ::RubyLsp::Addon
       extend T::Sig
 
+      sig { returns(T.nilable(String)) }
+      attr_reader :rspec_command
+
+      sig { returns(T::Boolean) }
+      attr_reader :debug
+
+      sig { void }
+      def initialize
+        super
+        @debug = T.let(false, T::Boolean)
+        @rspec_command = T.let(nil, T.nilable(String))
+      end
+
       sig { override.params(global_state: GlobalState, message_queue: Thread::Queue).void }
       def activate(global_state, message_queue)
         @index = T.let(global_state.index, T.nilable(RubyIndexer::Index))
+
+        settings = global_state.settings_for_addon(name)
+        @rspec_command = T.let(settings&.dig(:rspecCommand), T.nilable(String))
+        @debug = settings&.dig(:debug) || false
       end
 
       sig { override.void }
@@ -38,7 +55,7 @@ def version
       def create_code_lens_listener(response_builder, uri, dispatcher)
         return unless uri.to_standardized_path&.end_with?("_test.rb") || uri.to_standardized_path&.end_with?("_spec.rb")
 
-        CodeLens.new(response_builder, uri, dispatcher)
+        CodeLens.new(response_builder, uri, dispatcher, rspec_command: rspec_command, debug: debug)
       end
 
       sig do

lib/ruby_lsp/ruby_lsp_rspec/code_lens.rb

@@ -13,9 +13,11 @@ class CodeLens
           response_builder: ResponseBuilders::CollectionResponseBuilder[Interface::CodeLens],
           uri: URI::Generic,
           dispatcher: Prism::Dispatcher,
+          rspec_command: T.nilable(String),
+          debug: T::Boolean,
         ).void
       end
-      def initialize(response_builder, uri, dispatcher)
+      def initialize(response_builder, uri, dispatcher, rspec_command: nil, debug: false)
         @response_builder = response_builder
         # Listener is only initialized if uri.to_standardized_path is valid
         @path = T.let(T.must(uri.to_standardized_path), String)
@@ -24,8 +26,10 @@ def initialize(response_builder, uri, dispatcher)
         @anonymous_example_count = T.let(0, Integer)
         dispatcher.register(self, :on_call_node_enter, :on_call_node_leave)
 
+        @debug = debug
         @base_command = T.let(
-          begin
+          # The user-configured command takes precedence over inferred command default
+          rspec_command || begin
             cmd = if File.exist?(File.join(Dir.pwd, "bin", "rspec"))
               "bin/rspec"
             else
@@ -71,6 +75,11 @@ def on_call_node_leave(node)
 
       private
 
+      sig { params(message: String).void }
+      def log_message(message)
+        puts "[#{self.class}]: #{message}"
+      end
+
       sig { params(node: Prism::CallNode).returns(T::Boolean) }
       def valid_group?(node)
         !(node.block.nil? || (node.receiver && node.receiver&.slice != "RSpec"))
@@ -104,6 +113,8 @@ def add_test_code_lens(node, name:, kind:)
         line_number = node.location.start_line
         command = "#{@base_command} #{@path}:#{line_number}"
 
+        log_message("Full command: `#{command}`") if @debug
+
         grouping_data = { group_id: @group_id_stack.last, kind: kind }
         grouping_data[:id] = @group_id if kind == :group
 

spec/code_lens_spec.rb

@@ -161,6 +161,43 @@
       end
     end
 
+    context "with a custom rspec command configured" do
+      let(:configuration) do
+        {
+          rspecCommand: "docker compose run --rm web rspec",
+        }
+      end
+
+      before do
+        allow_any_instance_of(RubyLsp::GlobalState).to receive(:settings_for_addon).and_return(configuration)
+      end
+
+      it "uses the configured rspec command" do
+        source = <<~RUBY
+          RSpec.describe Foo do
+            it "does something" do
+            end
+          end
+        RUBY
+
+        with_server(source, uri) do |server, uri|
+          server.process_message(
+            {
+              id: 1,
+              method: "textDocument/codeLens",
+              params: {
+                textDocument: { uri: uri },
+                position: { line: 0, character: 0 },
+              },
+            },
+          )
+
+          response = pop_result(server).response
+          expect(response[0].command.arguments[2]).to eq("docker compose run --rm web rspec /fake_spec.rb:1")
+        end
+      end
+    end
+
     context "when the file is not a test file" do
       let(:uri) { URI("file:///not_spec_file.rb") }