[ruby/reline] Fix completion quote, preposing and target calculation

bug
(https://github.com/ruby/reline/pull/763)

https://github.com/ruby/reline/commit/d3ba7216eb

lib/reline/line_editor.rb

@@ -1225,70 +1225,35 @@ class Reline::LineEditor
   end
 
   def retrieve_completion_block(set_completion_quote_character = false)
-    if Reline.completer_word_break_characters.empty?
-      word_break_regexp = nil
-    else
-      word_break_regexp = /\A[#{Regexp.escape(Reline.completer_word_break_characters)}]/
-    end
-    if Reline.completer_quote_characters.empty?
-      quote_characters_regexp = nil
-    else
-      quote_characters_regexp = /\A[#{Regexp.escape(Reline.completer_quote_characters)}]/
-    end
-    before = current_line.byteslice(0, @byte_pointer)
-    rest = nil
-    break_pointer = nil
+    quote_characters = Reline.completer_quote_characters
+    before = current_line.byteslice(0, @byte_pointer).grapheme_clusters
     quote = nil
-    closing_quote = nil
-    escaped_quote = nil
-    i = 0
-    while i < @byte_pointer do
-      slice = current_line.byteslice(i, @byte_pointer - i)
-      unless slice.valid_encoding?
-        i += 1
-        next
-      end
-      if quote and slice.start_with?(closing_quote)
-        quote = nil
-        i += 1
-        rest = nil
-      elsif quote and slice.start_with?(escaped_quote)
-        # skip
-        i += 2
-      elsif quote_characters_regexp and slice =~ quote_characters_regexp # find new "
-        rest = $'
-        quote = $&
-        closing_quote = /(?!\\)#{Regexp.escape(quote)}/
-        escaped_quote = /\\#{Regexp.escape(quote)}/
-        i += 1
-        break_pointer = i - 1
-      elsif word_break_regexp and not quote and slice =~ word_break_regexp
-        rest = $'
-        i += 1
-        before = current_line.byteslice(i, @byte_pointer - i)
-        break_pointer = i
-      else
-        i += 1
-      end
-    end
-    postposing = current_line.byteslice(@byte_pointer, current_line.bytesize - @byte_pointer)
-    if rest
-      preposing = current_line.byteslice(0, break_pointer)
-      target = rest
-      if set_completion_quote_character and quote
-        Reline.core.instance_variable_set(:@completion_quote_character, quote)
-        if postposing !~ /(?!\\)#{Regexp.escape(quote)}/ # closing quote
-          insert_text(quote)
+    unless quote_characters.empty?
+      escaped = false
+      before.each do |c|
+        if escaped
+          escaped = false
+          next
+        elsif c == '\\'
+          escaped = true
+        elsif quote
+          quote = nil if c == quote
+        elsif quote_characters.include?(c)
+          quote = c
         end
       end
-    else
-      preposing = ''
-      if break_pointer
-        preposing = current_line.byteslice(0, break_pointer)
-      else
-        preposing = ''
+    end
+    word_break_characters = quote_characters + Reline.completer_word_break_characters
+    break_index = before.rindex { |c| word_break_characters.include?(c) || quote_characters.include?(c) } || -1
+    preposing = before.take(break_index + 1).join
+    target = before.drop(break_index + 1).join
+    postposing = current_line.byteslice(@byte_pointer, current_line.bytesize - @byte_pointer)
+    if target
+      if set_completion_quote_character and quote
+        Reline.core.instance_variable_set(:@completion_quote_character, quote)
+        insert_text(quote) # FIXME: should not be here
+        target += quote
       end
-      target = before
     end
     lines = whole_lines
     if @line_index > 0

test/reline/test_key_actor_emacs.rb

@@ -853,28 +853,6 @@ class Reline::KeyActor::EmacsTest < Reline::TestCase
     assert_equal(%w{foo_foo foo_bar foo_baz}, @line_editor.instance_variable_get(:@menu_info).list)
   end
 
-  def test_completion_with_indent_and_completer_quote_characters
-    @line_editor.completion_proc = proc { |word|
-      %w{
-        "".foo_foo
-        "".foo_bar
-        "".foo_baz
-        "".qux
-      }.map { |i|
-        i.encode(@encoding)
-      }
-    }
-    input_keys('  "".fo')
-    assert_line_around_cursor('  "".fo', '')
-    assert_equal(nil, @line_editor.instance_variable_get(:@menu_info))
-    input_keys("\C-i", false)
-    assert_line_around_cursor('  "".foo_', '')
-    assert_equal(nil, @line_editor.instance_variable_get(:@menu_info))
-    input_keys("\C-i", false)
-    assert_line_around_cursor('  "".foo_', '')
-    assert_equal(%w{"".foo_foo "".foo_bar "".foo_baz}, @line_editor.instance_variable_get(:@menu_info).list)
-  end
-
   def test_completion_with_perfect_match
     @line_editor.completion_proc = proc { |word|
       %w{

test/reline/test_line_editor.rb

@@ -3,6 +3,66 @@ require 'reline/line_editor'
 require 'stringio'
 
 class Reline::LineEditor
+
+  class CompletionBlockTest < Reline::TestCase
+    def setup
+      @original_quote_characters = Reline.completer_quote_characters
+      @original_word_break_characters = Reline.completer_word_break_characters
+      @line_editor = Reline::LineEditor.new(nil, Encoding::UTF_8)
+    end
+
+    def retrieve_completion_block(lines, line_index, byte_pointer)
+      @line_editor.instance_variable_set(:@buffer_of_lines, lines)
+      @line_editor.instance_variable_set(:@line_index, line_index)
+      @line_editor.instance_variable_set(:@byte_pointer, byte_pointer)
+      @line_editor.retrieve_completion_block(false)
+    end
+
+    def retrieve_completion_quote(line)
+      retrieve_completion_block([line], 0, line.bytesize)
+      _, target = @line_editor.retrieve_completion_block(false)
+      _, target2 = @line_editor.retrieve_completion_block(true)
+      # This is a hack to get the quoted character.
+      # retrieve_completion_block should be refactored to return the quoted character.
+      target2.chars.last if target2 != target
+    end
+
+    def teardown
+      Reline.completer_quote_characters = @original_quote_characters
+      Reline.completer_word_break_characters = @original_word_break_characters
+    end
+
+    def test_retrieve_completion_block
+      Reline.completer_word_break_characters = ' ([{'
+      Reline.completer_quote_characters = ''
+      assert_equal(['', '', 'foo'], retrieve_completion_block(['foo'], 0, 0))
+      assert_equal(['', 'f', 'oo'], retrieve_completion_block(['foo'], 0, 1))
+      assert_equal(['foo ', 'ba', 'r baz'], retrieve_completion_block(['foo bar baz'], 0, 6))
+      assert_equal(['foo([', 'b', 'ar])baz'], retrieve_completion_block(['foo([bar])baz'], 0, 6))
+      assert_equal(['foo([{', '', '}])baz'], retrieve_completion_block(['foo([{}])baz'], 0, 6))
+      assert_equal(["abc\nfoo ", 'ba', "r baz\ndef"], retrieve_completion_block(['abc', 'foo bar baz', 'def'], 1, 6))
+    end
+
+    def test_retrieve_completion_block_with_quote_characters
+      Reline.completer_word_break_characters = ' ([{'
+      Reline.completer_quote_characters = ''
+      assert_equal(['"" ', '"wo', 'rd'], retrieve_completion_block(['"" "word'], 0, 6))
+      Reline.completer_quote_characters = '"'
+      assert_equal(['"" "', 'wo', 'rd'], retrieve_completion_block(['"" "word'], 0, 6))
+    end
+
+    def test_retrieve_completion_quote
+      Reline.completer_quote_characters = '"\''
+      assert_equal('"', retrieve_completion_quote('"\''))
+      assert_equal(nil, retrieve_completion_quote('""'))
+      assert_equal("'", retrieve_completion_quote('""\'"'))
+      assert_equal(nil, retrieve_completion_quote('""\'\''))
+      assert_equal('"', retrieve_completion_quote('"\\"'))
+      assert_equal(nil, retrieve_completion_quote('"\\""'))
+      assert_equal(nil, retrieve_completion_quote('"\\\\"'))
+    end
+  end
+
   class RenderLineDifferentialTest < Reline::TestCase
     class TestIO < Reline::IO
       def move_cursor_column(col)