Search history to back in the middle of histories

lib/reline/line_editor.rb

@@ -1145,10 +1145,12 @@ class Reline::LineEditor
   alias_method :end_of_line, :ed_move_to_end
 
   private def ed_search_prev_history(key)
-    if @is_multiline
-      @line_backup_in_history = whole_buffer
-    else
-      @line_backup_in_history = @line
+    unless @history_pointer
+      if @is_multiline
+        @line_backup_in_history = whole_buffer
+      else
+        @line_backup_in_history = @line
+      end
     end
     searcher = Fiber.new do
       search_word = String.new(encoding: @encoding)
@@ -1171,7 +1173,7 @@ class Reline::LineEditor
           end
         end
         hit = nil
-        if @line_backup_in_history.include?(search_word)
+        if @line_backup_in_history&.include?(search_word)
           @history_pointer = nil
           hit = @line_backup_in_history
         else

test/reline/test_key_actor_emacs.rb

@@ -1430,6 +1430,28 @@ class Reline::KeyActor::Emacs::Test < Reline::TestCase
     assert_cursor_max(0)
   end
 
+  def test_search_history_to_back_in_the_middle_of_histories
+    Reline::HISTORY.concat([
+      '1235', # old
+      '12aa',
+      '1234' # new
+    ])
+    assert_line('')
+    assert_byte_pointer_size('')
+    assert_cursor(0)
+    assert_cursor_max(0)
+    input_keys("\C-p\C-p")
+    assert_line('12aa')
+    assert_byte_pointer_size('12aa')
+    assert_cursor(4)
+    assert_cursor_max(4)
+    input_keys("\C-r123")
+    assert_line('1235')
+    assert_byte_pointer_size('1235')
+    assert_cursor(4)
+    assert_cursor_max(4)
+  end
+
   def test_em_set_mark_and_em_exchange_mark
     input_keys('aaa bbb ccc ddd')
     assert_byte_pointer_size('aaa bbb ccc ddd')