Implement dynamic selection of candidates

Author: aycabta

lib/reline.rb

@@ -183,15 +183,22 @@ def readmultiline(prompt = '', add_hist = false, &confirm_multiline_termination)
       end
       @dialog_proc = ->() {
         # autocomplete
-        if just_cursor_moving
+        if just_cursor_moving and completion_journey_data.nil?
           # Auto complete starts only when edited
           return nil
         end
         pre, target, post= retrieve_completion_block(true)
         if target.nil? or target.empty?
           return nil
         end
-        result = call_completion_proc_with_checking_args(pre, target, post)
+        if completion_journey_data and completion_journey_data.list
+          result = completion_journey_data.list.dup
+          result.shift
+          pointer = completion_journey_data.pointer - 1
+        else
+          result = call_completion_proc_with_checking_args(pre, target, post)
+          pointer = nil
+        end
         if result and result.size == 1 and result[0] == target
           result = nil
         end
@@ -203,7 +210,7 @@ def readmultiline(prompt = '', add_hist = false, &confirm_multiline_termination)
         else
           y = 0
         end
-        [Reline::CursorPos.new(x, y), result]
+        [Reline::CursorPos.new(x, y), result, pointer]
       }
       inner_readline(prompt, add_hist, true, &confirm_multiline_termination)
 

lib/reline/line_editor.rb

@@ -514,6 +514,10 @@ def screen_width
       @line_editor.instance_variable_get(:@screen_size).last
     end
 
+    def completion_journey_data
+      @line_editor.instance_variable_get(:@completion_journey_data)
+    end
+
     def call
       instance_exec(&@proc_to_exec)
     end
@@ -533,7 +537,7 @@ def dialog_proc=(p)
       return
     end
     @dialog_proc_scope.set_cursor_pos(cursor_column, @first_line_started_from + @started_from)
-    pos, result = @dialog_proc_scope.call
+    pos, result, pointer = @dialog_proc_scope.call
     old_dialog_contents = @dialog_contents
     old_dialog_contents_width = @dialog_contents_width
     old_dialog_column = @dialog_column
@@ -582,7 +586,12 @@ def dialog_proc=(p)
     move_cursor_down(@dialog_vertical_offset)
     Reline::IOGate.move_cursor_column(@dialog_column)
     @dialog_contents.each_with_index do |item, i|
-      @output.write "\e[46m%-#{DIALOG_WIDTH}s\e[49m" % item.slice(0, DIALOG_WIDTH)
+      if i == pointer
+        bg_color = '45'
+      else
+        bg_color = '46'
+      end
+      @output.write "\e[#{bg_color}m%-#{DIALOG_WIDTH}s\e[49m" % item.slice(0, DIALOG_WIDTH)
       Reline::IOGate.move_cursor_column(@dialog_column)
       move_cursor_down(1) if i < (@dialog_contents.size - 1)
     end