[ruby/reline] Enter newline if cursor position is middle of input

(https://github.com/ruby/reline/pull/802)

* Enter newline if cursor position is middle of input

* Add ed_force_submit to allow input confirmation on non-final lines

https://github.com/ruby/reline/commit/8ef534e904

lib/reline/line_editor.rb

@@ -1673,17 +1673,10 @@ class Reline::LineEditor
           finish
         end
       else
-        if @line_index == (@buffer_of_lines.size - 1)
-          if confirm_multiline_termination
-            finish
-          else
-            key_newline(key)
-          end
-        else
-          # should check confirm_multiline_termination to finish?
-          @line_index = @buffer_of_lines.size - 1
-          @byte_pointer = current_line.bytesize
+        if @line_index == @buffer_of_lines.size - 1 && confirm_multiline_termination
           finish
+        else
+          key_newline(key)
         end
       end
     else
@@ -1691,6 +1684,11 @@ class Reline::LineEditor
     end
   end
 
+  private def ed_force_submit(_key)
+    process_insert(force: true)
+    finish
+  end
+
   private def em_delete_prev_char(key, arg: 1)
     arg.times do
       if @byte_pointer == 0 and @line_index > 0

test/reline/yamatanooroti/test_rendering.rb

@@ -813,13 +813,30 @@ begin
       close
     end
 
-    def test_terminate_in_the_middle_of_lines
+    def test_newline_in_the_middle_of_lines
       start_terminal(5, 20, %W{ruby -I#{@pwd}/lib #{@pwd}/test/reline/yamatanooroti/multiline_repl}, startup_message: 'Multiline REPL.')
       write("def hoge\n  1\n  2\n  3\n  4\nend\n")
       write("\C-p\C-p\C-p\C-e\n")
       assert_screen(<<~EOC)
+        prompt> def hoge
+        prompt>   1
+        prompt>   2
         prompt>   3
-        prompt>   4
+        prompt>
+      EOC
+      close
+    end
+
+    def test_ed_force_submit_in_the_middle_of_lines
+      write_inputrc <<~LINES
+        "\\C-a": ed_force_submit
+      LINES
+      start_terminal(5, 20, %W{ruby -I#{@pwd}/lib #{@pwd}/test/reline/yamatanooroti/multiline_repl}, startup_message: 'Multiline REPL.')
+      write("def hoge\nend")
+      write("\C-p\C-a")
+      assert_screen(<<~EOC)
+        Multiline REPL.
+        prompt> def hoge
         prompt> end
         => :hoge
         prompt>