Fix bracketed paste and scrolling bug (#801)

* Fix set_pasting_state bug with bracketed paste

* Fix rendered cursor_y caching in case of rendering the screen without scroll_into_view

Author: tompng

lib/reline.rb

@@ -341,7 +341,6 @@ def readline(prompt = '', add_hist = false)
         line_editor.set_signal_handlers
         loop do
           read_io(config.keyseq_timeout) { |inputs|
-            line_editor.set_pasting_state(io_gate.in_pasting?)
             inputs.each do |key|
               case key.method_symbol
               when :bracketed_paste_start
@@ -350,14 +349,14 @@ def readline(prompt = '', add_hist = false)
               when :quoted_insert, :ed_quoted_insert
                 key = Reline::Key.new(io_gate.read_single_char(config.keyseq_timeout), :insert_raw_char)
               end
+              line_editor.set_pasting_state(io_gate.in_pasting?)
               line_editor.update(key)
             end
           }
           if line_editor.finished?
             line_editor.render_finished
             break
           else
-            line_editor.set_pasting_state(io_gate.in_pasting?)
             line_editor.rerender
           end
         end

lib/reline/line_editor.rb

@@ -542,6 +542,7 @@ def render
       Reline::IOGate.show_cursor
     end
     Reline::IOGate.move_cursor_column new_cursor_x
+    new_cursor_y = new_cursor_y.clamp(0, screen_height - 1)
     Reline::IOGate.move_cursor_down new_cursor_y - cursor_y
     @rendered_screen.cursor_y = new_cursor_y
   ensure

test/reline/yamatanooroti/test_rendering.rb

@@ -550,6 +550,14 @@ def test_bracketed_paste
         prompt>   3
         prompt> end
       EOC
+      write("\e[200~.tap do\r\t4\r\t5\rend\e[201~")
+      assert_screen(<<~EOC)
+        prompt>   3
+        prompt> end.tap do
+        prompt>   4
+        prompt>   5
+        prompt> end
+      EOC
       close
     end