diff options
Diffstat (limited to 'lib/dialyzer/test/small_tests_SUITE_data/src/bs_utf8.erl')
-rw-r--r-- | lib/dialyzer/test/small_tests_SUITE_data/src/bs_utf8.erl | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/lib/dialyzer/test/small_tests_SUITE_data/src/bs_utf8.erl b/lib/dialyzer/test/small_tests_SUITE_data/src/bs_utf8.erl new file mode 100644 index 0000000000..5fe28f1da1 --- /dev/null +++ b/lib/dialyzer/test/small_tests_SUITE_data/src/bs_utf8.erl @@ -0,0 +1,27 @@ +%%-------------------------------------------------------------------- +%% Test case that exposed a bug (bogus warning) in dialyzer_dataflow +%% when refining binaries containing UTF-based segments. Reported by +%% Patrik Nyblom on 4/3/2009 and fixed by Kostis Sagonas on 31/3/2009. +%%-------------------------------------------------------------------- + +-module(bs_utf8). + +-export([doit/2]). + +doit(N, Bin) when is_integer(N), N > 0 -> + count_and_find(Bin, N). + +count_and_find(Bin, N) when is_binary(Bin) -> + cafu(Bin, N, 0, 0, no_pos). + +cafu(<<>>, _N, Count, _ByteCount, SavePos) -> + {Count, SavePos}; +cafu(<<_/utf8, Rest/binary>>, 0, Count, ByteCount, _SavePos) -> + cafu(Rest, -1, Count+1, 0, ByteCount); +cafu(<<_/utf8, Rest/binary>>, N, Count, _ByteCount, SavePos) when N < 0 -> + cafu(Rest, -1, Count+1, 0, SavePos); +cafu(<<_/utf8, Rest/binary>> = Whole, N, Count, ByteCount, SavePos) -> + Delta = byte_size(Whole) - byte_size(Rest), + cafu(Rest, N-1, Count+1, ByteCount+Delta, SavePos); +cafu(_Other, _N, Count, ByteCount, _SavePos) -> % Non Unicode character at end + {Count, ByteCount}. |