From 324fc38bc442460f871f3ae002dd853415ae9e51 Mon Sep 17 00:00:00 2001 From: Hans Bolinder Date: Thu, 24 May 2018 12:21:21 +0200 Subject: dialyzer: Refine the test for overspecified functions The -Woverspecs (-Wspecdiffs) option generates warnings in a few more cases. The refinement is analogous to the test that -Wunderspecs already does: it checks if the contract has nothing in common with some element (see erl_types:t_elements/1) of the success typing. --- .../test/specdiffs_SUITE_data/src/iolist.erl | 41 ++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 lib/dialyzer/test/specdiffs_SUITE_data/src/iolist.erl (limited to 'lib/dialyzer/test/specdiffs_SUITE_data/src/iolist.erl') diff --git a/lib/dialyzer/test/specdiffs_SUITE_data/src/iolist.erl b/lib/dialyzer/test/specdiffs_SUITE_data/src/iolist.erl new file mode 100644 index 0000000000..7cceeda24e --- /dev/null +++ b/lib/dialyzer/test/specdiffs_SUITE_data/src/iolist.erl @@ -0,0 +1,41 @@ +-module(iolist). + +%% A small part of beam_asm. + +-export([encode/2]). + +-spec encode(non_neg_integer(), integer()) -> iolist(). + +encode(Tag, N) when Tag >= 0, N < 0 -> + encode1(Tag, negative_to_bytes(N)); +encode(Tag, N) when Tag >= 0, N < 16 -> + (N bsl 4) bor Tag; % not in the specification +encode(Tag, N) when Tag >= 0, N < 16#800 -> + [((N bsr 3) band 2#11100000) bor Tag bor 2#00001000, N band 16#ff]; +encode(Tag, N) when Tag >= 0 -> + encode1(Tag, to_bytes(N)). + +encode1(Tag, Bytes) -> + case iolist_size(Bytes) of + Num when 2 =< Num, Num =< 8 -> + [((Num-2) bsl 5) bor 2#00011000 bor Tag| Bytes]; + Num when 8 < Num -> + [2#11111000 bor Tag, encode(0, Num-9)| Bytes] + end. + +to_bytes(N) -> + Bin = binary:encode_unsigned(N), + case Bin of + <<0:1,_/bits>> -> Bin; + <<1:1,_/bits>> -> [0,Bin] + end. + +negative_to_bytes(N) when N >= -16#8000 -> + <>; +negative_to_bytes(N) -> + Bytes = byte_size(binary:encode_unsigned(-N)), + Bin = <>, + case Bin of + <<0:1,_/bits>> -> [16#ff,Bin]; + <<1:1,_/bits>> -> Bin + end. -- cgit v1.2.3