message: features2d(test): add crossCheck=true test
diff: @@ -558,4 +558,23 @@ TEST( Features2d_DMatch, read_write )
  ASSERT_NE( strstr(str.c_str(), "4.5"), (char*)0 );
  }
  +
  +TEST(Features2d_DMatch, issue_11855)
  +{
  + Mat sources = (Mat_<uchar>(2, 3) << 1, 1, 0,
  + 1, 1, 1);
  + Mat targets = (Mat_<uchar>(2, 3) << 1, 1, 1,
  + 0, 0, 0);
  +
  + Ptr<BFMatcher> bf = BFMatcher::create(NORM_HAMMING, true);
  + vector<vector<DMatch> > match;
  + bf->knnMatch(sources, targets, match, 1, noArray(), true);
  +
  + ASSERT_EQ((size_t)1, match.size());
  + ASSERT_EQ((size_t)1, match[0].size());
  + EXPECT_EQ(1, match[0][0].queryIdx);
  + EXPECT_EQ(0, match[0][0].trainIdx);
  + EXPECT_EQ(0.0f, match[0][0].distance);
  +}
  +
  }} // namespace
  