From b72ee00ebd565b64f699cc76bf464774b1a28834 Mon Sep 17 00:00:00 2001 From: Hans Bolinder Date: Tue, 6 Mar 2018 14:28:04 +0100 Subject: stdlib: Improve io_lib:limit_term/2 Improve handling of maps. Addendum to b57e890. --- lib/stdlib/src/io_lib.erl | 58 ++++++++++++++++++++++---------------------- lib/stdlib/test/io_SUITE.erl | 30 +++++++++++++++++++++-- 2 files changed, 57 insertions(+), 31 deletions(-) (limited to 'lib') diff --git a/lib/stdlib/src/io_lib.erl b/lib/stdlib/src/io_lib.erl index cacd9f2524..e37c13093b 100644 --- a/lib/stdlib/src/io_lib.erl +++ b/lib/stdlib/src/io_lib.erl @@ -931,7 +931,7 @@ limit_term(Term, Depth) -> limit(_, 0) -> '...'; limit([H|T]=L, D) -> if - D =:= 1 -> '...'; + D =:= 1 -> ['...']; true -> case printable_list(L) of true -> L; @@ -944,7 +944,7 @@ limit(Term, D) when is_map(Term) -> limit({}=T, _D) -> T; limit(T, D) when is_tuple(T) -> if - D =:= 1 -> '...'; + D =:= 1 -> {'...'}; true -> list_to_tuple([limit(element(1, T), D-1)| limit_tail(tl(tuple_to_list(T)), D-1)]) @@ -961,32 +961,29 @@ limit_tail(Other, D) -> %% Cannot limit maps properly since there is no guarantee that %% maps:from_list() creates a map with the same internal ordering of -%% the selected associations as in Map. +%% the selected associations as in Map. Instead of subtracting one +%% from the depth as the map associations are traversed (as is done +%% for tuples and lists), the same depth is applied to each and every +%% (returned) association. limit_map(Map, D) -> - limit_map(maps:iterator(Map), D, []). + %% Keep one extra association to make sure the final ',...' is included. + limit_map_body(maps:iterator(Map), D + 1, D, []). -limit_map(_I, 0, Acc) -> +limit_map_body(_I, 0, _D0, Acc) -> maps:from_list(Acc); -limit_map(I, D, Acc) -> +limit_map_body(I, D, D0, Acc) -> case maps:next(I) of {K, V, NextI} -> - limit_map(NextI, D-1, [{K,V} | Acc]); + limit_map_body(NextI, D-1, D0, [limit_map_assoc(K, V, D0) | Acc]); none -> maps:from_list(Acc) end. -%% maps:from_list(limit_map_body(erts_internal:maps_to_list(Map, D), D)). +limit_map_assoc(K, V, D) -> + %% Keep keys as are to avoid creating duplicated keys. + {K, limit(V, D - 1)}. -%% limit_map_body(_, 0) -> [{'...', '...'}]; -%% limit_map_body([], _) -> []; -%% limit_map_body([{K,V}], D) -> [limit_map_assoc(K, V, D)]; -%% limit_map_body([{K,V}|KVs], D) -> -%% [limit_map_assoc(K, V, D) | limit_map_body(KVs, D-1)]. - -%% limit_map_assoc(K, V, D) -> -%% {limit(K, D-1), limit(V, D-1)}. - -limit_bitstring(B, _D) -> B. %% Keeps all printable binaries. +limit_bitstring(B, _D) -> B. % Keeps all printable binaries. test_limit(_, 0) -> throw(limit); test_limit([H|T]=L, D) when is_integer(D) -> @@ -1022,18 +1019,21 @@ test_limit_tuple(T, I, Sz, D) -> test_limit(element(I, T), D-1), test_limit_tuple(T, I+1, Sz, D-1). -test_limit_map(_Map, _D) -> ok. -%% test_limit_map_body(erts_internal:maps_to_list(Map, D), D). +test_limit_map(Map, D) -> + test_limit_map_body(maps:iterator(Map), D). -%% test_limit_map_body(_, 0) -> throw(limit); -%% test_limit_map_body([], _) -> ok; -%% test_limit_map_body([{K,V}], D) -> test_limit_map_assoc(K, V, D); -%% test_limit_map_body([{K,V}|KVs], D) -> -%% test_limit_map_assoc(K, V, D), -%% test_limit_map_body(KVs, D-1). +test_limit_map_body(_I, 0) -> throw(limit); % cannot happen +test_limit_map_body(I, D) -> + case maps:next(I) of + {K, V, NextI} -> + test_limit_map_assoc(K, V, D), + test_limit_map_body(NextI, D-1); + none -> + ok + end. -%% test_limit_map_assoc(K, V, D) -> -%% test_limit(K, D-1), -%% test_limit(V, D-1). +test_limit_map_assoc(K, V, D) -> + test_limit(K, D - 1), + test_limit(V, D - 1). test_limit_bitstring(_, _) -> ok. diff --git a/lib/stdlib/test/io_SUITE.erl b/lib/stdlib/test/io_SUITE.erl index 45363c0592..d29f4c016d 100644 --- a/lib/stdlib/test/io_SUITE.erl +++ b/lib/stdlib/test/io_SUITE.erl @@ -2384,19 +2384,36 @@ limit_term(_Config) -> {_, 2} = limt({a,b,c,[d,e]}, 2), {_, 2} = limt({a,b,c,[d,e]}, 3), {_, 2} = limt({a,b,c,[d,e]}, 4), + T0 = [1|{a,b,c}], + {_, 2} = limt(T0, 2), + {_, 2} = limt(T0, 3), + {_, 2} = limt(T0, 4), {_, 1} = limt(<<"foo">>, 18), + {_, 2} = limt({"",[1,2]}, 3), + {_, 2} = limt({"",{1,2}}, 3), + true = limt_pp({"123456789012345678901234567890",{1,2}}, 3), ok = blimt(<<"123456789012345678901234567890">>), + true = limt_pp(<<"123456789012345678901234567890">>, 3), + {_, 2} = limt({<<"kljlkjsl">>,[1,2,3,4]}, 4), {_, 1} = limt(<<7:3>>, 2), {_, 1} = limt(<<7:21>>, 2), {_, 1} = limt([], 2), {_, 1} = limt({}, 2), + {_, 1} = limt({"", ""}, 4), {_, 1} = limt(#{}, 2), - {_, 1} = limt(#{[] => {}}, 2), + {_, 2} = limt(#{[] => {}}, 1), + {_, 2} = limt(#{[] => {}}, 2), {_, 1} = limt(#{[] => {}}, 3), T = #{[] => {},[a] => [b]}, - {_, 1} = limt(T, 2), + {_, 1} = limt(T, 0), + {_, 2} = limt(T, 1), + {_, 2} = limt(T, 2), {_, 1} = limt(T, 3), {_, 1} = limt(T, 4), + T2 = #{[] => {},{} => []}, + {_, 2} = limt(T2, 1), + {_, 2} = limt(T2, 2), + {_, 1} = limt(T2, 3), ok. blimt(Binary) -> @@ -2430,3 +2447,12 @@ limt(Term, Depth) when is_integer(Depth) -> form(Term, Depth) -> lists:flatten(io_lib:format("~W", [Term, Depth])). + +limt_pp(Term, Depth) when is_integer(Depth) -> + T1 = io_lib:limit_term(Term, Depth), + S = pp(Term, Depth), + S1 = pp(T1, Depth), + S1 =:= S. + +pp(Term, Depth) -> + lists:flatten(io_lib:format("~P", [Term, Depth])). -- cgit v1.2.3