[ruby/reline] Add ed_search_prev_history

https://github.com/ruby/reline/commit/e9ae288825

lib/reline/line_editor.rb

@@ -1421,6 +1421,53 @@ 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 = @line.slice(0, @byte_pointer)
+    if @history_pointer.nil?
+      return if not @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
+    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
+      @line = @buffer_of_lines.last
+      @rerender_all = true
+    else
+      @line = Reline::HISTORY[@history_pointer]
+    end
+    @cursor_max = calculate_width(@line)
+    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_prev_history(key, arg: 1)
     if @is_multiline and @line_index > 0
       @previous_line_index = @line_index

test/reline/test_key_actor_emacs.rb

@@ -1912,6 +1912,75 @@ class Reline::KeyActor::Emacs::Test < Reline::TestCase
     $VERBOSE = verbose
   end
 
+  def test_ed_search_prev_history
+    Reline::HISTORY.concat([
+      '12356', # old
+      '12aaa',
+      '12345' # new
+    ])
+    input_keys('123')
+    # The ed_search_prev_history doesn't have default binding
+    @line_editor.__send__(:ed_search_prev_history, "\C-p".ord)
+    assert_byte_pointer_size('123')
+    assert_cursor(3)
+    assert_cursor_max(5)
+    assert_line('12345')
+    @line_editor.__send__(:ed_search_prev_history, "\C-p".ord)
+    assert_byte_pointer_size('123')
+    assert_cursor(3)
+    assert_cursor_max(5)
+    assert_line('12356')
+    @line_editor.__send__(:ed_search_prev_history, "\C-p".ord)
+    assert_byte_pointer_size('123')
+    assert_cursor(3)
+    assert_cursor_max(5)
+    assert_line('12356')
+  end
+
+  def test_ed_search_prev_history_with_empty
+    Reline::HISTORY.concat([
+      '12356', # old
+      '12aaa',
+      '12345' # new
+    ])
+    # The ed_search_prev_history doesn't have default binding
+    @line_editor.__send__(:ed_search_prev_history, "\C-p".ord)
+    assert_byte_pointer_size('')
+    assert_cursor(0)
+    assert_cursor_max(5)
+    assert_line('12345')
+    @line_editor.__send__(:ed_search_prev_history, "\C-p".ord)
+    assert_byte_pointer_size('')
+    assert_cursor(0)
+    assert_cursor_max(5)
+    assert_line('12aaa')
+    @line_editor.__send__(:ed_search_prev_history, "\C-p".ord)
+    assert_byte_pointer_size('')
+    assert_cursor(0)
+    assert_cursor_max(5)
+    assert_line('12356')
+    @line_editor.__send__(:ed_search_prev_history, "\C-p".ord)
+    assert_byte_pointer_size('')
+    assert_cursor(0)
+    assert_cursor_max(5)
+    assert_line('12356')
+  end
+
+  def test_ed_search_prev_history_without_match
+    Reline::HISTORY.concat([
+      '12356', # old
+      '12aaa',
+      '12345' # new
+    ])
+    input_keys('ABC')
+    # The ed_search_prev_history doesn't have default binding
+    @line_editor.__send__(:ed_search_prev_history, "\C-p".ord)
+    assert_byte_pointer_size('ABC')
+    assert_cursor(3)
+    assert_cursor_max(3)
+    assert_line('ABC')
+  end
+
 =begin # TODO: move KeyStroke instance from Reline to LineEditor
   def test_key_delete
     input_keys('ab')