[ruby/reline] Refactor history move and history search

(https://github.com/ruby/reline/pull/651)

https://github.com/ruby/reline/commit/90e43e01d4

1 files changed, 134 insertions, 265 deletions

diff --git a/lib/reline/line_editor.rb b/lib/reline/line_editor.rb
index 36bd6d435f..c84a78a06c 100644
--- a/lib/reline/line_editor.rb
+++ b/lib/reline/line_editor.rb
@@ -1543,118 +1543,89 @@ class Reline::LineEditor
   end
   alias_method :end_of_line, :ed_move_to_end
 
-  private def generate_searcher
-    Fiber.new do |first_key|
-      prev_search_key = first_key
-      search_word = String.new(encoding: @encoding)
-      multibyte_buf = String.new(encoding: 'ASCII-8BIT')
-      last_hit = nil
-      case first_key
-      when "\C-r".ord
-        prompt_name = 'reverse-i-search'
-      when "\C-s".ord
-        prompt_name = 'i-search'
+  private def generate_searcher(search_key)
+    search_word = String.new(encoding: @encoding)
+    multibyte_buf = String.new(encoding: 'ASCII-8BIT')
+    last_hit = nil
+    hit_pointer = nil
+    lambda do |key|
+      search_again = false
+      case key
+      when "\C-h".ord, "\C-?".ord
+        grapheme_clusters = search_word.grapheme_clusters
+        if grapheme_clusters.size > 0
+          grapheme_clusters.pop
+          search_word = grapheme_clusters.join
+        end
+      when "\C-r".ord, "\C-s".ord
+        search_again = true if search_key == key
+        search_key = key
+      else
+        multibyte_buf << key
+        if multibyte_buf.dup.force_encoding(@encoding).valid_encoding?
+          search_word << multibyte_buf.dup.force_encoding(@encoding)
+          multibyte_buf.clear
+        end
       end
-      loop do
-        key = Fiber.yield(search_word)
-        search_again = false
-        case key
-        when -1 # determined
-          Reline.last_incremental_search = search_word
-          break
-        when "\C-h".ord, "\C-?".ord
-          grapheme_clusters = search_word.grapheme_clusters
-          if grapheme_clusters.size > 0
-            grapheme_clusters.pop
-            search_word = grapheme_clusters.join
-          end
-        when "\C-r".ord, "\C-s".ord
-          search_again = true if prev_search_key == key
-          prev_search_key = key
-        else
-          multibyte_buf << key
-          if multibyte_buf.dup.force_encoding(@encoding).valid_encoding?
-            search_word << multibyte_buf.dup.force_encoding(@encoding)
-            multibyte_buf.clear
+      hit = nil
+      if not search_word.empty? and @line_backup_in_history&.include?(search_word)
+        hit_pointer = Reline::HISTORY.size
+        hit = @line_backup_in_history
+      else
+        if search_again
+          if search_word.empty? and Reline.last_incremental_search
+            search_word = Reline.last_incremental_search
           end
-        end
-        hit = nil
-        if not search_word.empty? and @line_backup_in_history&.include?(search_word)
-          @history_pointer = nil
-          hit = @line_backup_in_history
-        else
-          if search_again
-            if search_word.empty? and Reline.last_incremental_search
-              search_word = Reline.last_incremental_search
-            end
-            if @history_pointer
-              case prev_search_key
-              when "\C-r".ord
-                history_pointer_base = 0
-                history = Reline::HISTORY[0..(@history_pointer - 1)]
-              when "\C-s".ord
-                history_pointer_base = @history_pointer + 1
-                history = Reline::HISTORY[(@history_pointer + 1)..-1]
-              end
-            else
-              history_pointer_base = 0
-              history = Reline::HISTORY
-            end
-          elsif @history_pointer
-            case prev_search_key
+          if @history_pointer
+            case search_key
             when "\C-r".ord
               history_pointer_base = 0
-              history = Reline::HISTORY[0..@history_pointer]
+              history = Reline::HISTORY[0..(@history_pointer - 1)]
             when "\C-s".ord
-              history_pointer_base = @history_pointer
-              history = Reline::HISTORY[@history_pointer..-1]
+              history_pointer_base = @history_pointer + 1
+              history = Reline::HISTORY[(@history_pointer + 1)..-1]
             end
           else
             history_pointer_base = 0
             history = Reline::HISTORY
           end
-          case prev_search_key
+        elsif @history_pointer
+          case search_key
           when "\C-r".ord
-            hit_index = history.rindex { |item|
-              item.include?(search_word)
-            }
+            history_pointer_base = 0
+            history = Reline::HISTORY[0..@history_pointer]
           when "\C-s".ord
-            hit_index = history.index { |item|
-              item.include?(search_word)
-            }
-          end
-          if hit_index
-            @history_pointer = history_pointer_base + hit_index
-            hit = Reline::HISTORY[@history_pointer]
+            history_pointer_base = @history_pointer
+            history = Reline::HISTORY[@history_pointer..-1]
           end
+        else
+          history_pointer_base = 0
+          history = Reline::HISTORY
         end
-        case prev_search_key
+        case search_key
         when "\C-r".ord
-          prompt_name = 'reverse-i-search'
+          hit_index = history.rindex { |item|
+            item.include?(search_word)
+          }
         when "\C-s".ord
-          prompt_name = 'i-search'
+          hit_index = history.index { |item|
+            item.include?(search_word)
+          }
         end
-        if hit
-          if @is_multiline
-            @buffer_of_lines = hit.split("\n")
-            @buffer_of_lines = [String.new(encoding: @encoding)] if @buffer_of_lines.empty?
-            @line_index = @buffer_of_lines.size - 1
-            @byte_pointer = current_line.bytesize
-            @searching_prompt = "(%s)`%s'" % [prompt_name, search_word]
-          else
-            @buffer_of_lines = [hit]
-            @byte_pointer = hit.bytesize
-            @searching_prompt = "(%s)`%s': %s" % [prompt_name, search_word, hit]
-          end
-          last_hit = hit
-        else
-          if @is_multiline
-            @searching_prompt = "(failed %s)`%s'" % [prompt_name, search_word]
-          else
-            @searching_prompt = "(failed %s)`%s': %s" % [prompt_name, search_word, last_hit]
-          end
+        if hit_index
+          hit_pointer = history_pointer_base + hit_index
+          hit = Reline::HISTORY[hit_pointer]
         end
       end
+      case search_key
+      when "\C-r".ord
+        prompt_name = 'reverse-i-search'
+      when "\C-s".ord
+        prompt_name = 'i-search'
+      end
+      prompt_name = "failed #{prompt_name}" unless hit
+      last_hit = hit if hit_pointer
+      [search_word, prompt_name, hit_pointer, hit, last_hit]
     end
   end
 
@@ -1666,8 +1637,7 @@ class Reline::LineEditor
         @line_backup_in_history = current_line
       end
     end
-    searcher = generate_searcher
-    searcher.resume(key)
+    searcher = generate_searcher(key)
     @searching_prompt = "(reverse-i-search)`': "
     termination_keys = ["\C-j".ord]
     termination_keys.concat(@config.isearch_terminators&.chars&.map(&:ord)) if @config.isearch_terminators
@@ -1689,7 +1659,6 @@ class Reline::LineEditor
         @searching_prompt = nil
         @waiting_proc = nil
         @byte_pointer = 0
-        searcher.resume(-1)
       when "\C-g".ord
         if @is_multiline
           @buffer_of_lines = @line_backup_in_history.split("\n")
@@ -1698,15 +1667,21 @@ class Reline::LineEditor
         else
           @buffer_of_lines = [@line_backup_in_history]
         end
-        @history_pointer = nil
+        move_history(nil, line: :end, cursor: :end, save_buffer: false)
         @searching_prompt = nil
         @waiting_proc = nil
-        @line_backup_in_history = nil
         @byte_pointer = 0
       else
         chr = k.is_a?(String) ? k : k.chr(Encoding::ASCII_8BIT)
         if chr.match?(/[[:print:]]/) or k == "\C-h".ord or k == "\C-?".ord or k == "\C-r".ord or k == "\C-s".ord
-          searcher.resume(k)
+          search_word, prompt_name, hit_pointer, hit, last_hit = searcher.call(k)
+          Reline.last_incremental_search = search_word
+          if @is_multiline
+            @searching_prompt = "(%s)`%s'" % [prompt_name, search_word]
+          else
+            @searching_prompt = "(%s)`%s': %s" % [prompt_name, search_word, hit || last_hit]
+          end
+          move_history(hit_pointer, line: :end, cursor: :end, save_buffer: false) if hit_pointer
         else
           if @history_pointer
             line = Reline::HISTORY[@history_pointer]
@@ -1725,7 +1700,6 @@ class Reline::LineEditor
           @searching_prompt = nil
           @waiting_proc = nil
           @byte_pointer = 0
-          searcher.resume(-1)
         end
       end
     }
@@ -1741,104 +1715,70 @@ class Reline::LineEditor
   end
   alias_method :forward_search_history, :vi_search_next
 
-  private def ed_search_prev_history(key, arg: 1)
-    history = nil
-    h_pointer = nil
-    line_no = nil
-    substr = current_line.slice(0, @byte_pointer)
-    if @history_pointer.nil?
-      return if not current_line.empty? and substr.empty?
-      history = Reline::HISTORY
-    elsif @history_pointer.zero?
-      history = nil
-      h_pointer = nil
-    else
-      history = Reline::HISTORY.slice(0, @history_pointer)
-    end
-    return if history.nil?
-    if @is_multiline
-      h_pointer = history.rindex { |h|
-        h.split("\n").each_with_index { |l, i|
-          if l.start_with?(substr)
-            line_no = i
-            break
-          end
-        }
-        not line_no.nil?
-      }
-    else
-      h_pointer = history.rindex { |l|
-        l.start_with?(substr)
-      }
-    end
-    return if h_pointer.nil?
-    @history_pointer = h_pointer
-    cursor = current_byte_pointer_cursor
-    if @is_multiline
-      @buffer_of_lines = Reline::HISTORY[@history_pointer].split("\n")
-      @buffer_of_lines = [String.new(encoding: @encoding)] if @buffer_of_lines.empty?
-      @line_index = line_no
-      calculate_nearest_cursor(cursor)
-    else
-      @buffer_of_lines = [Reline::HISTORY[@history_pointer]]
-      calculate_nearest_cursor(cursor)
+  private def search_history(prefix, pointer_range)
+    pointer_range.each do |pointer|
+      lines = Reline::HISTORY[pointer].split("\n")
+      lines.each_with_index do |line, index|
+        return [pointer, index] if line.start_with?(prefix)
+      end
     end
+    nil
+  end
+
+  private def ed_search_prev_history(key, arg: 1)
+    substr = current_line.byteslice(0, @byte_pointer)
+    return if @history_pointer == 0
+    return if @history_pointer.nil? && substr.empty? && !current_line.empty?
+
+    history_range = 0...(@history_pointer || Reline::HISTORY.size)
+    h_pointer, line_index = search_history(substr, history_range.reverse_each)
+    return unless h_pointer
+    move_history(h_pointer, line: line_index || :start, cursor: @byte_pointer)
     arg -= 1
     ed_search_prev_history(key, arg: arg) if arg > 0
   end
   alias_method :history_search_backward, :ed_search_prev_history
 
   private def ed_search_next_history(key, arg: 1)
-    substr = current_line.slice(0, @byte_pointer)
-    if @history_pointer.nil?
-      return
-    elsif @history_pointer == (Reline::HISTORY.size - 1) and not substr.empty?
-      return
-    end
+    substr = current_line.byteslice(0, @byte_pointer)
+    return if @history_pointer.nil?
+
+    history_range = @history_pointer + 1...Reline::HISTORY.size
     history = Reline::HISTORY.slice((@history_pointer + 1)..-1)
-    h_pointer = nil
-    line_no = nil
-    if @is_multiline
-      h_pointer = history.index { |h|
-        h.split("\n").each_with_index { |l, i|
-          if l.start_with?(substr)
-            line_no = i
-            break
-          end
-        }
-        not line_no.nil?
-      }
+    h_pointer, line_index = search_history(substr, history_range)
+    return if h_pointer.nil? and not substr.empty?
+
+    move_history(h_pointer, line: line_index || :start, cursor: @byte_pointer)
+    arg -= 1
+    ed_search_next_history(key, arg: arg) if arg > 0
+  end
+  alias_method :history_search_forward, :ed_search_next_history
+
+  private def move_history(history_pointer, line:, cursor:, save_buffer: true)
+    history_pointer ||= Reline::HISTORY.size
+    return if history_pointer < 0 || history_pointer > Reline::HISTORY.size
+    old_history_pointer = @history_pointer || Reline::HISTORY.size
+    if old_history_pointer == Reline::HISTORY.size
+      @line_backup_in_history = save_buffer ? whole_buffer : ''
     else
-      h_pointer = history.index { |l|
-        l.start_with?(substr)
-      }
+      Reline::HISTORY[old_history_pointer] = whole_buffer if save_buffer
+    end
+    if history_pointer == Reline::HISTORY.size
+      buf = @line_backup_in_history
+      @history_pointer = @line_backup_in_history = nil
+    else
+      buf = Reline::HISTORY[history_pointer]
+      @history_pointer = history_pointer
     end
-    h_pointer += @history_pointer + 1 if h_pointer and @history_pointer
-    return if h_pointer.nil? and not substr.empty?
-    @history_pointer = h_pointer
     if @is_multiline
-      if @history_pointer.nil? and substr.empty?
-        @buffer_of_lines = []
-        @line_index = 0
-        @byte_pointer = 0
-      else
-        cursor = current_byte_pointer_cursor
-        @buffer_of_lines = Reline::HISTORY[@history_pointer].split("\n")
-        @line_index = line_no
-        calculate_nearest_cursor(cursor)
-      end
+      @buffer_of_lines = buf.split("\n")
       @buffer_of_lines = [String.new(encoding: @encoding)] if @buffer_of_lines.empty?
+      @line_index = line == :start ? 0 : line == :end ? @buffer_of_lines.size - 1 : line
     else
-      if @history_pointer.nil? and substr.empty?
-        set_current_line('', 0)
-      else
-        set_current_line(Reline::HISTORY[@history_pointer])
-      end
+      @buffer_of_lines = [buf]
     end
-    arg -= 1
-    ed_search_next_history(key, arg: arg) if arg > 0
+    @byte_pointer = cursor == :start ? 0 : cursor == :end ? current_line.bytesize : cursor
   end
-  alias_method :history_search_forward, :ed_search_next_history
 
   private def ed_prev_history(key, arg: 1)
     if @is_multiline and @line_index > 0
@@ -1847,43 +1787,11 @@ class Reline::LineEditor
       calculate_nearest_cursor(cursor)
       return
     end
-    if Reline::HISTORY.empty?
-      return
-    end
-    if @history_pointer.nil?
-      @history_pointer = Reline::HISTORY.size - 1
-      cursor = current_byte_pointer_cursor
-      if @is_multiline
-        @line_backup_in_history = whole_buffer
-        @buffer_of_lines = Reline::HISTORY[@history_pointer].split("\n")
-        @buffer_of_lines = [String.new(encoding: @encoding)] if @buffer_of_lines.empty?
-        @line_index = @buffer_of_lines.size - 1
-        calculate_nearest_cursor(cursor)
-      else
-        @line_backup_in_history = whole_buffer
-        @buffer_of_lines = [Reline::HISTORY[@history_pointer]]
-        calculate_nearest_cursor(cursor)
-      end
-    elsif @history_pointer.zero?
-      return
-    else
-      if @is_multiline
-        Reline::HISTORY[@history_pointer] = whole_buffer
-        @history_pointer -= 1
-        @buffer_of_lines = Reline::HISTORY[@history_pointer].split("\n")
-        @buffer_of_lines = [String.new(encoding: @encoding)] if @buffer_of_lines.empty?
-        @line_index = @buffer_of_lines.size - 1
-      else
-        Reline::HISTORY[@history_pointer] = whole_buffer
-        @history_pointer -= 1
-        @buffer_of_lines = [Reline::HISTORY[@history_pointer]]
-      end
-    end
-    if @config.editing_mode_is?(:emacs, :vi_insert)
-      @byte_pointer = current_line.bytesize
-    elsif @config.editing_mode_is?(:vi_command)
-      @byte_pointer = 0
-    end
+    move_history(
+      (@history_pointer || Reline::HISTORY.size) - 1,
+      line: :end,
+      cursor: @config.editing_mode_is?(:vi_command) ? :start : :end,
+    )
     arg -= 1
     ed_prev_history(key, arg: arg) if arg > 0
   end
@@ -1896,36 +1804,11 @@ class Reline::LineEditor
       calculate_nearest_cursor(cursor)
       return
     end
-    if @history_pointer.nil?
-      return
-    elsif @history_pointer == (Reline::HISTORY.size - 1)
-      if @is_multiline
-        @history_pointer = nil
-        @buffer_of_lines = @line_backup_in_history.split("\n")
-        @buffer_of_lines = [String.new(encoding: @encoding)] if @buffer_of_lines.empty?
-        @line_index = 0
-      else
-        @history_pointer = nil
-        @buffer_of_lines = [@line_backup_in_history]
-      end
-    else
-      if @is_multiline
-        Reline::HISTORY[@history_pointer] = whole_buffer
-        @history_pointer += 1
-        @buffer_of_lines = Reline::HISTORY[@history_pointer].split("\n")
-        @buffer_of_lines = [String.new(encoding: @encoding)] if @buffer_of_lines.empty?
-        @line_index = 0
-      else
-        Reline::HISTORY[@history_pointer] = whole_buffer
-        @history_pointer += 1
-        @buffer_of_lines = [Reline::HISTORY[@history_pointer]]
-      end
-    end
-    if @config.editing_mode_is?(:emacs, :vi_insert)
-      @byte_pointer = current_line.bytesize
-    elsif @config.editing_mode_is?(:vi_command)
-      @byte_pointer = 0
-    end
+    move_history(
+      (@history_pointer || Reline::HISTORY.size) + 1,
+      line: :start,
+      cursor: @config.editing_mode_is?(:vi_command) ? :start : :end,
+    )
     arg -= 1
     ed_next_history(key, arg: arg) if arg > 0
   end
@@ -1956,10 +1839,6 @@ class Reline::LineEditor
         end
       end
     else
-      if @history_pointer
-        Reline::HISTORY[@history_pointer] = whole_buffer
-        @history_pointer = nil
-      end
       finish
     end
   end
@@ -2409,17 +2288,7 @@ class Reline::LineEditor
     if Reline::HISTORY.empty?
       return
     end
-    if @history_pointer.nil?
-      @history_pointer = 0
-      @line_backup_in_history = current_line
-      set_current_line(Reline::HISTORY[@history_pointer], 0)
-    elsif @history_pointer.zero?
-      return
-    else
-      Reline::HISTORY[@history_pointer] = current_line
-      @history_pointer = 0
-      set_current_line(Reline::HISTORY[@history_pointer], 0)
-    end
+    move_history(0, line: :start, cursor: :start)
   end
 
   private def vi_histedit(key)