Improve go to relevant file performance

By doing a walk over the tree of directories in the workpsace we improve
the dir Glob time because it only checks for the closest test directory
folder, instead of searching in all the files of the workspace.

Author: domingo2000

lib/ruby_lsp/requests/go_to_relevant_file.rb

@@ -35,12 +35,53 @@ def perform
 
       #: -> Array[String]
       def find_relevant_paths
-        candidate_paths = Dir.glob(File.join("**", relevant_filename_pattern))
+        pattern = File.join(search_root, "**", relevant_filename_pattern)
+        candidate_paths = Dir.glob(pattern)
+          .uniq
+          .map { |path| path.delete_prefix(@workspace_path).delete_prefix("/") }
+
         return [] if candidate_paths.empty?
 
         find_most_similar_with_jaccard(candidate_paths).map { File.join(@workspace_path, _1) }
       end
 
+      # Determine the search roots based on the closest test directories.
+      # This scopes the search to reduce the number of files that need to be checked.
+      #: -> String
+      def search_root
+        current_path = File.join(@workspace_path, @path)
+
+        current_dir = File.dirname(current_path)
+        while current_dir != @workspace_path
+          dir_basename = File.basename(current_dir)
+
+          # If current directory is a test directory, return its parent as search root
+          if TEST_KEYWORDS.include?(dir_basename)
+            return File.dirname(current_dir)
+          end
+
+          # Search the test directories by walking up the directory tree
+          begin
+            contains_test_dir = Dir
+              .entries(current_dir)
+              .filter { |entry| TEST_KEYWORDS.include?(entry) }
+              .any? { |entry| File.directory?(File.join(current_dir, entry)) }
+
+            return current_dir if contains_test_dir
+          rescue Errno::EACCES, Errno::ENOENT
+            # Skip directories we can't read
+          end
+
+          # Move up one level
+          parent_dir = File.dirname(current_dir)
+          break if parent_dir == current_dir
+
+          current_dir = parent_dir
+        end
+
+        @workspace_path
+      end
+
       #: -> String
       def relevant_filename_pattern
         input_basename = File.basename(@path, File.extname(@path))

test/requests/go_to_relevant_file_test.rb

@@ -5,6 +5,7 @@
 
 class GoToRelevantFileTest < Minitest::Test
   def test_when_input_is_test_file_returns_array_of_implementation_file_locations
+    stub_directory_structure("/workspace/test/requests", has_test_dir: false)
     stub_glob_pattern("**/go_to_relevant_file.rb", ["lib/ruby_lsp/requests/go_to_relevant_file.rb"])
 
     test_file_path = "/workspace/test/requests/go_to_relevant_file_test.rb"
@@ -15,8 +16,12 @@ def test_when_input_is_test_file_returns_array_of_implementation_file_locations
   end
 
   def test_when_input_is_implementation_file_returns_array_of_test_file_locations
-    pattern =
-      "**/{{test_,spec_,integration_test_}go_to_relevant_file,go_to_relevant_file{_test,_spec,_integration_test}}.rb"
+    stub_directory_structure("/workspace/lib/ruby_lsp/requests", has_test_dir: false)
+    stub_directory_structure("/workspace/lib/ruby_lsp", has_test_dir: false)
+    stub_directory_structure("/workspace/lib", has_test_dir: false)
+    stub_directory_structure("/workspace", has_test_dir: true)
+
+    pattern = "**/{{test_,spec_,integration_test_}go_to_relevant_file,go_to_relevant_file{_test,_spec,_integration_test}}.rb"
     stub_glob_pattern(pattern, ["test/requests/go_to_relevant_file_test.rb"])
 
     impl_path = "/workspace/lib/ruby_lsp/requests/go_to_relevant_file.rb"
@@ -149,6 +154,21 @@ def test_it_finds_integration_tests_for_implementation
   private
 
   def stub_glob_pattern(pattern, matches)
-    Dir.stubs(:glob).with(pattern).returns(matches)
+    absolute_pattern = pattern.start_with?("/") ? pattern : "/workspace/#{pattern}"
+    absolute_matches = matches.map { |match| match.start_with?("/") ? match : "/workspace/#{match}" }
+    Dir.stubs(:glob).with(absolute_pattern).returns(absolute_matches)
+  end
+
+  def stub_directory_structure(dir_path, has_test_dir:)
+    File.stubs(:directory?).with(File.join(dir_path, "other_dir")).returns(true)
+
+    if has_test_dir
+      Dir.stubs(:entries).with(dir_path).returns([".", "..", "test", "lib", "other_dir"])
+      File.stubs(:directory?).with(File.join(dir_path, "test")).returns(true)
+      File.stubs(:directory?).with(File.join(dir_path, "lib")).returns(true)
+    else
+      Dir.stubs(:entries).with(dir_path).returns([".", "..", "some_file.rb", "other_dir"])
+      File.stubs(:directory?).with(File.join(dir_path, "some_file.rb")).returns(false)
+    end
   end
 end