From 0baa07cdf2754748bbc2d969bf83f08c0976fb78 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Mon, 15 Aug 2016 15:34:06 +0200 Subject: Fix overridden BIFs The filters in a list comprehension can be guard expressions or an ordinary expressions. If a guard expression is used as a filter, an exception will basically mean the same as 'false': t() -> L = [{some_tag,42},an_atom], [X || X <- L, element(1, X) =:= some_tag] %% Returns [{some_tag,42}] On the other hand, if an ordinary expression is used as a filter, there will be an exception: my_element(N, T) -> element(N, T). t() -> L = [{some_tag,42},an_atom], [X || X <- L, my_element(1, X) =:= some_tag] %% Causes a 'badarg' exception when element(1, an_atom) is evaluated It has been allowed for several releases to override a BIF with a local function. Thus, if we define a function called element/2, it will be called instead of the BIF element/2 within the module. We must use the "erlang:" prefix to call the BIF. Therefore, the following code is expected to work the same way as in our second example above: -compile({no_auto_import,[element/2]}). element(N, T) -> erlang:element(N, T). t() -> L = [{some_tag,42},an_atom], [X || X <- L, element(1, X) =:= some_tag]. %% Causes a 'badarg' exception when element(1, an_atom) is evaluated But the compiler refuses to compile the code with the following diagnostic: call to local/imported function element/2 is illegal in guard --- lib/compiler/test/Makefile | 3 + lib/compiler/test/overridden_bif_SUITE.erl | 101 +++++++++++++++++++++++++++++ lib/compiler/test/test_lib.erl | 9 ++- 3 files changed, 112 insertions(+), 1 deletion(-) create mode 100644 lib/compiler/test/overridden_bif_SUITE.erl (limited to 'lib/compiler/test') diff --git a/lib/compiler/test/Makefile b/lib/compiler/test/Makefile index 365f4c295e..de06e8760f 100644 --- a/lib/compiler/test/Makefile +++ b/lib/compiler/test/Makefile @@ -36,6 +36,7 @@ MODULES= \ map_SUITE \ match_SUITE \ misc_SUITE \ + overridden_bif_SUITE \ receive_SUITE \ record_SUITE \ regressions_SUITE \ @@ -66,6 +67,7 @@ NO_OPT= \ map \ match \ misc \ + overridden_bif \ receive \ record \ trycatch @@ -90,6 +92,7 @@ INLINE= \ map \ match \ misc \ + overridden_bif \ receive \ record diff --git a/lib/compiler/test/overridden_bif_SUITE.erl b/lib/compiler/test/overridden_bif_SUITE.erl new file mode 100644 index 0000000000..ce18916515 --- /dev/null +++ b/lib/compiler/test/overridden_bif_SUITE.erl @@ -0,0 +1,101 @@ +%% +%% %CopyrightBegin% +%% +%% Copyright Ericsson AB 2001-2016. All Rights Reserved. +%% +%% Licensed under the Apache License, Version 2.0 (the "License"); +%% you may not use this file except in compliance with the License. +%% You may obtain a copy of the License at +%% +%% http://www.apache.org/licenses/LICENSE-2.0 +%% +%% Unless required by applicable law or agreed to in writing, software +%% distributed under the License is distributed on an "AS IS" BASIS, +%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +%% See the License for the specific language governing permissions and +%% limitations under the License. +%% +%% %CopyrightEnd% +%% +-module(overridden_bif_SUITE). +-compile({no_auto_import,[is_reference/1,size/1]}). + +-export([all/0, suite/0,groups/0,init_per_suite/1, end_per_suite/1, + init_per_group/2,end_per_group/2, + init_per_testcase/2,end_per_testcase/2, + overridden_bif/1]). + +-include_lib("common_test/include/ct.hrl"). + +%% Used by overridden_bif/1. +-import(gb_sets, [size/1]). +-import(test_lib, [binary/1]). + +suite() -> + [{ct_hooks,[ts_install_cth]}, + {timetrap,{minutes,1}}]. + +all() -> + test_lib:recompile(?MODULE), + [{group,p}]. + +groups() -> + [{p,test_lib:parallel(), + [overridden_bif + ]}]. + +init_per_suite(Config) -> + Config. + +end_per_suite(_Config) -> + ok. + +init_per_group(_GroupName, Config) -> + Config. + +end_per_group(_GroupName, Config) -> + Config. + + +init_per_testcase(Case, Config) when is_atom(Case), is_list(Config) -> + Config. + +end_per_testcase(Case, Config) when is_atom(Case), is_list(Config) -> + ok. + +overridden_bif(_Config) -> + L = [-3,-2,-1,0,1,2,3,4], + [-3,0,3] = do_overridden_bif_1(L), + [-2,0,2,4] = do_overridden_bif_2(L), + [3] = do_overridden_bif_3(L), + [2,4] = do_overridden_bif_4(L), + + Set = gb_sets:from_list(L), + [Set] = do_overridden_bif_5([gb_sets:singleton(42),Set]), + + [100,0] = do_overridden_bif_6([100|L]), + ok. + +do_overridden_bif_1(L) -> + [E || E <- L, is_reference(E)]. + +do_overridden_bif_2(L) -> + [E || E <- L, port(E)]. + +do_overridden_bif_3(L) -> + [E || E <- L, (is_reference(E) andalso E > 0)]. + +do_overridden_bif_4(L) -> + [E || E <- L, (port(E) andalso E > 0)]. + +do_overridden_bif_5(L) -> + [E || E <- L, size(E) > 1]. + +do_overridden_bif_6(L) -> + [E || E <- L, binary(E)]. + +is_reference(N) -> + N rem 3 =:= 0. + +port(N) -> + N rem 2 =:= 0. diff --git a/lib/compiler/test/test_lib.erl b/lib/compiler/test/test_lib.erl index d5b79e2357..8954a9f5fb 100644 --- a/lib/compiler/test/test_lib.erl +++ b/lib/compiler/test/test_lib.erl @@ -22,7 +22,10 @@ -include_lib("common_test/include/ct.hrl"). -compile({no_auto_import,[binary_part/2]}). -export([id/1,recompile/1,parallel/0,uniq/0,opt_opts/1,get_data_dir/1, - is_cloned_mod/1,smoke_disasm/1,p_run/2,binary_part/2]). + is_cloned_mod/1,smoke_disasm/1,p_run/2]). + +%% Used by test case that override BIFs. +-export([binary_part/2,binary/1]). id(I) -> I. @@ -151,3 +154,7 @@ p_run_loop(Test, List, N, Refs0, Errors0, Ws0) -> %% This is for the misc_SUITE:override_bif testcase binary_part(_A,_B) -> dummy. + +%% This is for overridden_bif_SUITE. +binary(N) -> + N rem 10 =:= 0. -- cgit v1.2.3