Correct test IDs based on relative path

When running rspec from a parent directory the example's location used to generate the test IDs will not match how the tests are registered in the LSP.

By defining the envvar RUBY_LSP_RSPEC_RELPATH the path prefix will be removed for while generating the test IDs so that they align up.

Author: elmuerte

lib/ruby_lsp/ruby_lsp_rspec/rspec_formatter.rb

@@ -18,6 +18,7 @@ class RSpecFormatter
 
       def initialize(output)
         @output = output
+        @relative_path = ENV["RUBY_LSP_RSPEC_RELPATH"]
       end
 
       def example_started(notification)
@@ -59,7 +60,12 @@ def uri_for(example)
       end
 
       def generate_id(example)
-        [example, *example.example_group.parent_groups].reverse.map(&:location).join("::")
+        [example, *example.example_group.parent_groups].reverse.map(&:location).map(&method(:make_relative)).join("::")
+      end
+
+      def make_relative(location)
+        return location unless @relative_path
+        location.sub(/^#{@relative_path}/, "./")
       end
     end
   end