Add -e, --type, and --method-type options to rbs parse

lib/rbs/cli.rb

@@ -921,6 +921,10 @@ def run_vendor(args, options)
     end
 
     def run_parse(args, options)
+      parse_method = :parse_signature
+      # @type var e_code: String?
+      e_code = nil
+
       OptionParser.new do |opts|
         opts.banner = <<-EOB
 Usage: rbs parse [files...]
@@ -930,22 +934,37 @@ def run_parse(args, options)
 Examples:
 
   $ rbs parse sig/app/models.rbs sig/app/controllers.rbs
+
+Options:
         EOB
+
+        opts.on('-e CODE', 'One line RBS script to parse') { |e| e_code = e }
+        opts.on('--type', 'Parse code as a type') { |e| parse_method = :parse_type }
+        opts.on('--method-type', 'Parse code as a method type') { |e| parse_method = :parse_method_type }
       end.parse!(args)
 
       loader = options.loader()
 
       syntax_error = false
-      args.each do |path|
+      bufs = args.flat_map do |path|
         path = Pathname(path)
-        loader.each_file(path, skip_hidden: false, immediate: true) do |file_path|
-          RBS.logger.info "Parsing #{file_path}..."
-          buffer = Buffer.new(content: file_path.read, name: file_path)
-          Parser.parse_signature(buffer)
-        rescue RBS::ParsingError => ex
-          stdout.puts ex.message
-          syntax_error = true
+        loader.each_file(path, skip_hidden: false, immediate: true).map do |file_path|
+          Buffer.new(content: file_path.read, name: file_path)
+        end
+      end
+      bufs << Buffer.new(content: e_code, name: '-e') if e_code
+
+      bufs.each do |buf|
+        RBS.logger.info "Parsing #{buf.name}..."
+        case parse_method
+        when :parse_signature
+          Parser.parse_signature(buf)
+        else
+          Parser.public_send(parse_method, buf, require_eof: true)
         end
+      rescue RBS::ParsingError => ex
+        stdout.puts ex.message
+        syntax_error = true
       end
 
       exit 1 if syntax_error

lib/rbs/environment_loader.rb

@@ -130,6 +130,8 @@ def each_dir
     end
 
     def each_file(path, immediate:, skip_hidden:, &block)
+      return enum_for(__method__, path, immediate: immediate, skip_hidden: skip_hidden) unless block
+
       case
       when path.file?
         if path.extname == ".rbs" || immediate

sig/environment_loader.rbs

@@ -105,5 +105,6 @@ module RBS
     def each_dir: { (source, Pathname) -> void } -> void
 
     def each_file: (Pathname path, immediate: boolish, skip_hidden: boolish) { (Pathname) -> void } -> void
+                 | (Pathname path, immediate: boolish, skip_hidden: boolish) -> Enumerator[Pathname, void]
   end
 end

test/rbs/cli_test.rb

@@ -488,6 +488,42 @@ def foo: () -> void
     end
   end
 
+  def test_parse_e
+    with_cli do |cli|
+      cli.run(['parse', '-e', 'class C end'])
+      assert_empty stdout.string
+
+      assert_raises(SystemExit) { cli.run(['parse', '-e', 'class C en']) }
+      assert_equal [
+        "-e:1:8...1:10: Syntax error: unexpected token for class/module declaration member, token=`en` (tLIDENT)"
+      ], stdout.string.split("\n").sort
+    end
+  end
+
+  def test_parse_type
+    with_cli do |cli|
+      cli.run(['parse', '--type', '-e', 'bool'])
+      assert_empty stdout.string
+
+      assert_raises(SystemExit) { cli.run(['parse', '--type', '-e', '?']) }
+      assert_equal [
+        "-e:1:0...1:1: Syntax error: unexpected token for simple type, token=`?` (pQUESTION)",
+      ], stdout.string.split("\n").sort
+    end
+  end
+
+  def test_parse_method_type
+    with_cli do |cli|
+      cli.run(['parse', '--method-type', '-e', '() -> void'])
+      assert_empty stdout.string
+
+      assert_raises(SystemExit) { cli.run(['parse', '--method-type', '-e', '()']) }
+      assert_equal [
+        "-e:1:2...1:3: Syntax error: expected a token `pARROW`, token=`` (pEOF)",
+      ], stdout.string.split("\n").sort
+    end
+  end
+
   def test_prototype_no_parser
     Dir.mktmpdir do |dir|
       with_cli do |cli|