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diff --git a/lib/dialyzer/test/opaque_SUITE_data/src/proper/proper_types.erl b/lib/dialyzer/test/opaque_SUITE_data/src/proper/proper_types.erl new file mode 100644 index 0000000000..fe83a0ba11 --- /dev/null +++ b/lib/dialyzer/test/opaque_SUITE_data/src/proper/proper_types.erl @@ -0,0 +1,1349 @@ +%%% Copyright 2010-2013 Manolis Papadakis <[email protected]>, +%%% Eirini Arvaniti <[email protected]> +%%% and Kostis Sagonas <[email protected]> +%%% +%%% This file is part of PropEr. +%%% +%%% PropEr is free software: you can redistribute it and/or modify +%%% it under the terms of the GNU General Public License as published by +%%% the Free Software Foundation, either version 3 of the License, or +%%% (at your option) any later version. +%%% +%%% PropEr is distributed in the hope that it will be useful, +%%% but WITHOUT ANY WARRANTY; without even the implied warranty of +%%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +%%% GNU General Public License for more details. +%%% +%%% You should have received a copy of the GNU General Public License +%%% along with PropEr. If not, see <http://www.gnu.org/licenses/>. + +%%% @copyright 2010-2013 Manolis Papadakis, Eirini Arvaniti and Kostis Sagonas +%%% @version {@version} +%%% @author Manolis Papadakis + +%%% @doc Type manipulation functions and predefined types. +%%% +%%% == Basic types == +%%% This module defines all the basic types of the PropEr type system as +%%% functions. See the <a href="#index">function index</a> for an overview. +%%% +%%% Types can be combined in tuples or lists to produce other types. Exact +%%% values (such as exact numbers, atoms, binaries and strings) can be combined +%%% with types inside such structures, like in this example of the type of a +%%% tagged tuple: ``{'result', integer()}''. +%%% +%%% When including the PropEr header file, all +%%% <a href="#index">API functions</a> of this module are automatically +%%% imported, unless `PROPER_NO_IMPORTS' is defined. +%%% +%%% == Customized types == +%%% The following operators can be applied to basic types in order to produce +%%% new ones: +%%% +%%% <dl> +%%% <dt>`?LET(<Xs>, <Xs_type>, <In>)'</dt> +%%% <dd>To produce an instance of this type, all appearances of the variables +%%% in `<Xs>' are replaced inside `<In>' by their corresponding values in a +%%% randomly generated instance of `<Xs_type>'. It's OK for the `<In>' part to +%%% evaluate to a type - in that case, an instance of the inner type is +%%% generated recursively.</dd> +%%% <dt>`?SUCHTHAT(<X>, <Type>, <Condition>)'</dt> +%%% <dd>This produces a specialization of `<Type>', which only includes those +%%% members of `<Type>' that satisfy the constraint `<Condition>' - that is, +%%% those members for which the function `fun(<X>) -> <Condition> end' returns +%%% `true'. If the constraint is very strict - that is, only a small +%%% percentage of instances of `<Type>' pass the test - it will take a lot of +%%% tries for the instance generation subsystem to randomly produce a valid +%%% instance. This will result in slower testing, and testing may even be +%%% stopped short, in case the `constraint_tries' limit is reached (see the +%%% "Options" section in the documentation of the {@link proper} module). If +%%% this is the case, it would be more appropriate to generate valid instances +%%% of the specialized type using the `?LET' macro. Also make sure that even +%%% small instances can satisfy the constraint, since PropEr will only try +%%% small instances at the start of testing. If this is not possible, you can +%%% instruct PropEr to start at a larger size, by supplying a suitable value +%%% for the `start_size' option (see the "Options" section in the +%%% documentation of the {@link proper} module).</dd> +%%% <dt>`?SUCHTHATMAYBE(<X>, <Type>, <Condition>)'</dt> +%%% <dd>Equivalent to the `?SUCHTHAT' macro, but the constraint `<Condition>' +%%% is considered non-strict: if the `constraint_tries' limit is reached, the +%%% generator will just return an instance of `<Type>' instead of failing, +%%% even if that instance doesn't satisfy the constraint.</dd> +%%% <dt>`?SHRINK(<Generator>, <List_of_alt_gens>)'</dt> +%%% <dd>This creates a type whose instances are generated by evaluating the +%%% statement block `<Generator>' (this may evaluate to a type, which will +%%% then be generated recursively). If an instance of such a type is to be +%%% shrunk, the generators in `<List_of_alt_gens>' are first run to produce +%%% hopefully simpler instances of the type. Thus, the generators in the +%%% second argument should be simpler than the default. The simplest ones +%%% should be at the front of the list, since those are the generators +%%% preferred by the shrinking subsystem. Like the main `<Generator>', the +%%% alternatives may also evaluate to a type, which is generated recursively. +%%% </dd> +%%% <dt>`?LETSHRINK(<List_of_variables>, <List_of_types>, <Generator>)'</dt> +%%% <dd>This is created by combining a `?LET' and a `?SHRINK' macro. Instances +%%% are generated by applying a randomly generated list of values inside +%%% `<Generator>' (just like a `?LET', with the added constraint that the +%%% variables and types must be provided in a list - alternatively, +%%% `<List_of_types>' may be a list or vector type). When shrinking instances +%%% of such a type, the sub-instances that were combined to produce it are +%%% first tried in place of the failing instance.</dd> +%%% <dt>`?LAZY(<Generator>)'</dt> +%%% <dd>This construct returns a type whose only purpose is to delay the +%%% evaluation of `<Generator>' (`<Generator>' can return a type, which will +%%% be generated recursively). Using this, you can simulate the lazy +%%% generation of instances: +%%% ``` stream() -> ?LAZY(frequency([ {1,[]}, {3,[0|stream()]} ])). ''' +%%% The above type produces lists of zeroes with an average length of 3. Note +%%% that, had we not enclosed the generator with a `?LAZY' macro, the +%%% evaluation would continue indefinitely, due to the eager evaluation of +%%% the Erlang language.</dd> +%%% <dt>`non_empty(<List_or_binary_type>)'</dt> +%%% <dd>See the documentation for {@link non_empty/1}.</dd> +%%% <dt>`noshrink(<Type>)'</dt> +%%% <dd>See the documentation for {@link noshrink/1}.</dd> +%%% <dt>`default(<Default_value>, <Type>)'</dt> +%%% <dd>See the documentation for {@link default/2}.</dd> +%%% <dt>`with_parameter(<Parameter>, <Value>, <Type>)'</dt> +%%% <dd>See the documentation for {@link with_parameter/3}.</dd> +%%% <dt>`with_parameters(<Param_value_pairs>, <Type>)'</dt> +%%% <dd>See the documentation for {@link with_parameters/2}.</dd> +%%% </dl> +%%% +%%% == Size manipulation == +%%% The following operators are related to the `size' parameter, which controls +%%% the maximum size of produced instances. The actual size of a produced +%%% instance is chosen randomly, but can never exceed the value of the `size' +%%% parameter at the moment of generation. A more accurate definition is the +%%% following: the maximum instance of `size S' can never be smaller than the +%%% maximum instance of `size S-1'. The actual size of an instance is measured +%%% differently for each type: the actual size of a list is its length, while +%%% the actual size of a tree may be the number of its internal nodes. Some +%%% types, e.g. unions, have no notion of size, thus their generation is not +%%% influenced by the value of `size'. The `size' parameter starts at 1 and +%%% grows automatically during testing. +%%% +%%% <dl> +%%% <dt>`?SIZED(<S>, <Generator>)'</dt> +%%% <dd>Creates a new type, whose instances are produced by replacing all +%%% appearances of the `<S>' parameter inside the statement block +%%% `<Generator>' with the value of the `size' parameter. It's OK for the +%%% `<Generator>' to return a type - in that case, an instance of the inner +%%% type is generated recursively.</dd> +%%% <dt>`resize(<New_size>, <Type>)'</dt> +%%% <dd>See the documentation for {@link resize/2}.</dd> +%%% </dl> + +-module(proper_types). +-export([is_inst/2, is_inst/3]). + +-export([integer/2, float/2, atom/0, binary/0, binary/1, bitstring/0, + bitstring/1, list/1, vector/2, union/1, weighted_union/1, tuple/1, + loose_tuple/1, exactly/1, fixed_list/1, function/2, any/0, + shrink_list/1, safe_union/1, safe_weighted_union/1]). +-export([integer/0, non_neg_integer/0, pos_integer/0, neg_integer/0, range/2, + float/0, non_neg_float/0, number/0, boolean/0, byte/0, char/0, + list/0, tuple/0, string/0, wunion/1, term/0, timeout/0, arity/0]). +-export([int/0, nat/0, largeint/0, real/0, bool/0, choose/2, elements/1, + oneof/1, frequency/1, return/1, default/2, orderedlist/1, function0/1, + function1/1, function2/1, function3/1, function4/1, + weighted_default/2]). +-export([resize/2, non_empty/1, noshrink/1]). + +-export([cook_outer/1, is_type/1, equal_types/2, is_raw_type/1, to_binary/1, + from_binary/1, get_prop/2, find_prop/2, safe_is_instance/2, + is_instance/2, unwrap/1, weakly/1, strongly/1, satisfies_all/2, + new_type/2, subtype/2]). +-export([lazy/1, sized/1, bind/3, shrinkwith/2, add_constraint/3, + native_type/2, distlist/3, with_parameter/3, with_parameters/2, + parameter/1, parameter/2]). +-export([le/2]). + +-export_type([type/0, raw_type/0, extint/0, extnum/0]). + +-include("proper_internal.hrl"). + + +%%------------------------------------------------------------------------------ +%% Comparison with erl_types +%%------------------------------------------------------------------------------ + +%% Missing types +%% ------------------- +%% will do: +%% records, maybe_improper_list(T,S), nonempty_improper_list(T,S) +%% maybe_improper_list(), maybe_improper_list(T), iolist, iodata +%% don't need: +%% nonempty_{list,string,maybe_improper_list} +%% won't do: +%% pid, port, ref, identifier, none, no_return, module, mfa, node +%% array, dict, digraph, set, gb_tree, gb_set, queue, tid + +%% Missing type information +%% ------------------------ +%% bin types: +%% other unit sizes? what about size info? +%% functions: +%% generally some fun, unspecified number of arguments but specified +%% return type +%% any: +%% doesn't cover functions and improper lists + + +%%------------------------------------------------------------------------------ +%% Type declaration macros +%%------------------------------------------------------------------------------ + +-define(BASIC(PropList), new_type(PropList,basic)). +-define(WRAPPER(PropList), new_type(PropList,wrapper)). +-define(CONSTRUCTED(PropList), new_type(PropList,constructed)). +-define(CONTAINER(PropList), new_type(PropList,container)). +-define(SUBTYPE(Type,PropList), subtype(PropList,Type)). + + +%%------------------------------------------------------------------------------ +%% Types +%%------------------------------------------------------------------------------ + +-type type_kind() :: 'basic' | 'wrapper' | 'constructed' | 'container' | atom(). +-type instance_test() :: fun((proper_gen:imm_instance()) -> boolean()) + | {'typed', + fun((proper_types:type(), + proper_gen:imm_instance()) -> boolean())}. +-type index() :: pos_integer(). +%% @alias +-type value() :: term(). +%% @private_type +%% @alias +-type extint() :: integer() | 'inf'. +%% @private_type +%% @alias +-type extnum() :: number() | 'inf'. +-type constraint_fun() :: fun((proper_gen:instance()) -> boolean()). + +-opaque type() :: {'$type', [type_prop()]}. +%% A type of the PropEr type system +%% @type raw_type(). You can consider this as an equivalent of {@type type()}. +-type raw_type() :: type() | [raw_type()] | loose_tuple(raw_type()) | term(). +-type type_prop_name() :: 'kind' | 'generator' | 'reverse_gen' | 'parts_type' + | 'combine' | 'alt_gens' | 'shrink_to_parts' + | 'size_transform' | 'is_instance' | 'shrinkers' + | 'noshrink' | 'internal_type' | 'internal_types' + | 'get_length' | 'split' | 'join' | 'get_indices' + | 'remove' | 'retrieve' | 'update' | 'constraints' + | 'parameters' | 'env' | 'subenv'. + +-type type_prop_value() :: term(). +-type type_prop() :: + {'kind', type_kind()} + | {'generator', proper_gen:generator()} + | {'reverse_gen', proper_gen:reverse_gen()} + | {'parts_type', type()} + | {'combine', proper_gen:combine_fun()} + | {'alt_gens', proper_gen:alt_gens()} + | {'shrink_to_parts', boolean()} + | {'size_transform', fun((size()) -> size())} + | {'is_instance', instance_test()} + | {'shrinkers', [proper_shrink:shrinker()]} + | {'noshrink', boolean()} + | {'internal_type', raw_type()} + | {'internal_types', tuple() | maybe_improper_list(type(),type() | [])} + %% The items returned by 'remove' must be of this type. + | {'get_length', fun((proper_gen:imm_instance()) -> length())} + %% If this is a container type, this should return the number of elements + %% it contains. + | {'split', fun((proper_gen:imm_instance()) -> [proper_gen:imm_instance()]) + | fun((length(),proper_gen:imm_instance()) -> + {proper_gen:imm_instance(),proper_gen:imm_instance()})} + %% If present, the appropriate form depends on whether get_length is + %% defined: if get_length is undefined, this must be in the one-argument + %% form (e.g. a tree should be split into its subtrees), else it must be + %% in the two-argument form (e.g. a list should be split in two at the + %% index provided). + | {'join', fun((proper_gen:imm_instance(),proper_gen:imm_instance()) -> + proper_gen:imm_instance())} + | {'get_indices', fun((proper_types:type(), + proper_gen:imm_instance()) -> [index()])} + %% If this is a container type, this should return a list of indices we + %% can use to remove or insert elements from the given instance. + | {'remove', fun((index(),proper_gen:imm_instance()) -> + proper_gen:imm_instance())} + | {'retrieve', fun((index(), proper_gen:imm_instance() | tuple() + | maybe_improper_list(type(),type() | [])) -> + value() | type())} + | {'update', fun((index(),value(),proper_gen:imm_instance()) -> + proper_gen:imm_instance())} + | {'constraints', [{constraint_fun(), boolean()}]} + %% A list of constraints on instances of this type: each constraint is a + %% tuple of a fun that must return 'true' for each valid instance and a + %% boolean field that specifies whether the condition is strict. + | {'parameters', [{atom(),value()}]} + | {'env', term()} + | {'subenv', term()}. + + +%%------------------------------------------------------------------------------ +%% Type manipulation functions +%%------------------------------------------------------------------------------ + +%% TODO: We shouldn't need the fully qualified type name in the range of these +%% functions. + +%% @private +%% TODO: just cook/1 ? +-spec cook_outer(raw_type()) -> proper_types:type(). +cook_outer(Type = {'$type',_Props}) -> + Type; +cook_outer(RawType) -> + if + is_tuple(RawType) -> tuple(tuple_to_list(RawType)); + %% CAUTION: this must handle improper lists + is_list(RawType) -> fixed_list(RawType); + %% default case (covers integers, floats, atoms, binaries, ...): + true -> exactly(RawType) + end. + +%% @private +-spec is_type(term()) -> boolean(). +is_type({'$type',_Props}) -> + true; +is_type(_) -> + false. + +%% @private +-spec equal_types(proper_types:type(), proper_types:type()) -> boolean(). +equal_types(SameType, SameType) -> + true; +equal_types(_, _) -> + false. + +%% @private +-spec is_raw_type(term()) -> boolean(). +is_raw_type({'$type',_TypeProps}) -> + true; +is_raw_type(X) -> + if + is_tuple(X) -> is_raw_type_list(tuple_to_list(X)); + is_list(X) -> is_raw_type_list(X); + true -> false + end. + +-spec is_raw_type_list(maybe_improper_list()) -> boolean(). +%% CAUTION: this must handle improper lists +is_raw_type_list(List) -> + proper_arith:safe_any(fun is_raw_type/1, List). + +%% @private +-spec to_binary(proper_types:type()) -> binary(). +to_binary(Type) -> + term_to_binary(Type). + +%% @private +%% TODO: restore: -spec from_binary(binary()) -> proper_types:type(). +from_binary(Binary) -> + binary_to_term(Binary). + +-spec type_from_list([type_prop()]) -> proper_types:type(). +type_from_list(KeyValueList) -> + {'$type',KeyValueList}. + +-spec add_prop(type_prop_name(), type_prop_value(), proper_types:type()) -> + proper_types:type(). +add_prop(PropName, Value, {'$type',Props}) -> + {'$type',lists:keystore(PropName, 1, Props, {PropName, Value})}. + +-spec add_props([type_prop()], proper_types:type()) -> proper_types:type(). +add_props(PropList, {'$type',OldProps}) -> + {'$type', lists:foldl(fun({N,_}=NV,Acc) -> + lists:keystore(N, 1, Acc, NV) + end, OldProps, PropList)}. + +-spec append_to_prop(type_prop_name(), type_prop_value(), + proper_types:type()) -> proper_types:type(). +append_to_prop(PropName, Value, {'$type',Props}) -> + Val = case lists:keyfind(PropName, 1, Props) of + {PropName, V} -> + V; + _ -> + [] + end, + {'$type', lists:keystore(PropName, 1, Props, + {PropName, lists:reverse([Value|Val])})}. + +-spec append_list_to_prop(type_prop_name(), [type_prop_value()], + proper_types:type()) -> proper_types:type(). +append_list_to_prop(PropName, List, {'$type',Props}) -> + {PropName, Val} = lists:keyfind(PropName, 1, Props), + {'$type', lists:keystore(PropName, 1, Props, {PropName, Val++List})}. + +%% @private +-spec get_prop(type_prop_name(), proper_types:type()) -> type_prop_value(). +get_prop(PropName, {'$type',Props}) -> + {_PropName, Val} = lists:keyfind(PropName, 1, Props), + Val. + +%% @private +-spec find_prop(type_prop_name(), proper_types:type()) -> + {'ok',type_prop_value()} | 'error'. +find_prop(PropName, {'$type',Props}) -> + case lists:keyfind(PropName, 1, Props) of + {PropName, Value} -> + {ok, Value}; + _ -> + error + end. + +%% @private +-spec new_type([type_prop()], type_kind()) -> proper_types:type(). +new_type(PropList, Kind) -> + Type = type_from_list(PropList), + add_prop(kind, Kind, Type). + +%% @private +-spec subtype([type_prop()], proper_types:type()) -> proper_types:type(). +%% TODO: should the 'is_instance' function etc. be reset for subtypes? +subtype(PropList, Type) -> + add_props(PropList, Type). + +%% @private +-spec is_inst(proper_gen:instance(), raw_type()) -> + boolean() | {'error',{'typeserver',term()}}. +is_inst(Instance, RawType) -> + is_inst(Instance, RawType, 10). + +%% @private +-spec is_inst(proper_gen:instance(), raw_type(), size()) -> + boolean() | {'error',{'typeserver',term()}}. +is_inst(Instance, RawType, Size) -> + proper:global_state_init_size(Size), + Result = safe_is_instance(Instance, RawType), + proper:global_state_erase(), + Result. + +%% @private +-spec safe_is_instance(proper_gen:imm_instance(), raw_type()) -> + boolean() | {'error',{'typeserver',term()}}. +safe_is_instance(ImmInstance, RawType) -> + try is_instance(ImmInstance, RawType) catch + throw:{'$typeserver',SubReason} -> {error, {typeserver,SubReason}} + end. + +%% @private +-spec is_instance(proper_gen:imm_instance(), raw_type()) -> boolean(). +%% TODO: If the second argument is not a type, let it pass (don't even check for +%% term equality?) - if it's a raw type, don't cook it, instead recurse +%% into it. +is_instance(ImmInstance, RawType) -> + CleanInstance = proper_gen:clean_instance(ImmInstance), + Type = cook_outer(RawType), + (case get_prop(kind, Type) of + wrapper -> wrapper_test(ImmInstance, Type); + constructed -> constructed_test(ImmInstance, Type); + _ -> false + end + orelse + case find_prop(is_instance, Type) of + {ok,{typed, IsInstance}} -> IsInstance(Type, ImmInstance); + {ok,IsInstance} -> IsInstance(ImmInstance); + error -> false + end) + andalso weakly(satisfies_all(CleanInstance, Type)). + +-spec wrapper_test(proper_gen:imm_instance(), proper_types:type()) -> boolean(). +wrapper_test(ImmInstance, Type) -> + %% TODO: check if it's actually a raw type that's returned? + lists:any(fun(T) -> is_instance(ImmInstance, T) end, unwrap(Type)). + +%% @private +%% TODO: restore:-spec unwrap(proper_types:type()) -> [proper_types:type(),...]. +%% TODO: check if it's actually a raw type that's returned? +unwrap(Type) -> + RawInnerTypes = proper_gen:alt_gens(Type) ++ [proper_gen:normal_gen(Type)], + [cook_outer(T) || T <- RawInnerTypes]. + +-spec constructed_test(proper_gen:imm_instance(), proper_types:type()) -> + boolean(). +constructed_test({'$used',ImmParts,ImmInstance}, Type) -> + PartsType = get_prop(parts_type, Type), + Combine = get_prop(combine, Type), + is_instance(ImmParts, PartsType) andalso + begin + %% TODO: check if it's actually a raw type that's returned? + %% TODO: move construction code to proper_gen + %% TODO: non-type => should we check for strict term equality? + RawInnerType = Combine(proper_gen:clean_instance(ImmParts)), + is_instance(ImmInstance, RawInnerType) + end; +constructed_test({'$to_part',ImmInstance}, Type) -> + PartsType = get_prop(parts_type, Type), + get_prop(shrink_to_parts, Type) =:= true andalso + %% TODO: we reject non-container types + get_prop(kind, PartsType) =:= container andalso + case {find_prop(internal_type,PartsType), + find_prop(internal_types,PartsType)} of + {{ok,EachPartType},error} -> + %% The parts are in a list or a vector. + is_instance(ImmInstance, EachPartType); + {error,{ok,PartTypesList}} -> + %% The parts are in a fixed list. + %% TODO: It should always be a proper list. + lists:any(fun(T) -> is_instance(ImmInstance,T) end, PartTypesList) + end; +constructed_test(_CleanInstance, _Type) -> + %% TODO: can we do anything better? + false. + +%% @private +-spec weakly({boolean(),boolean()}) -> boolean(). +weakly({B1,_B2}) -> B1. + +%% @private +-spec strongly({boolean(),boolean()}) -> boolean(). +strongly({_B1,B2}) -> B2. + +-spec satisfies(proper_gen:instance(), {constraint_fun(),boolean()}) + -> {boolean(),boolean()}. +satisfies(Instance, {Test,false}) -> + {true,Test(Instance)}; +satisfies(Instance, {Test,true}) -> + Result = Test(Instance), + {Result,Result}. + +%% @private +-spec satisfies_all(proper_gen:instance(), proper_types:type()) -> + {boolean(),boolean()}. +satisfies_all(Instance, Type) -> + case find_prop(constraints, Type) of + {ok, Constraints} -> + L = [satisfies(Instance, C) || C <- Constraints], + {L1,L2} = lists:unzip(L), + {lists:all(fun(B) -> B end, L1), lists:all(fun(B) -> B end, L2)}; + error -> + {true,true} + end. + + +%%------------------------------------------------------------------------------ +%% Type definition functions +%%------------------------------------------------------------------------------ + +%% @private +-spec lazy(proper_gen:nosize_generator()) -> proper_types:type(). +lazy(Gen) -> + ?WRAPPER([ + {generator, Gen} + ]). + +%% @private +-spec sized(proper_gen:sized_generator()) -> proper_types:type(). +sized(Gen) -> + ?WRAPPER([ + {generator, Gen} + ]). + +%% @private +-spec bind(raw_type(), proper_gen:combine_fun(), boolean()) -> + proper_types:type(). +bind(RawPartsType, Combine, ShrinkToParts) -> + PartsType = cook_outer(RawPartsType), + ?CONSTRUCTED([ + {parts_type, PartsType}, + {combine, Combine}, + {shrink_to_parts, ShrinkToParts} + ]). + +%% @private +-spec shrinkwith(proper_gen:nosize_generator(), proper_gen:alt_gens()) -> + proper_types:type(). +shrinkwith(Gen, DelaydAltGens) -> + ?WRAPPER([ + {generator, Gen}, + {alt_gens, DelaydAltGens} + ]). + +%% @private +-spec add_constraint(raw_type(), constraint_fun(), boolean()) -> + proper_types:type(). +add_constraint(RawType, Condition, IsStrict) -> + Type = cook_outer(RawType), + append_to_prop(constraints, {Condition,IsStrict}, Type). + +%% @private +-spec native_type(mod_name(), string()) -> proper_types:type(). +native_type(Mod, TypeStr) -> + ?WRAPPER([ + {generator, fun() -> proper_gen:native_type_gen(Mod,TypeStr) end} + ]). + + +%%------------------------------------------------------------------------------ +%% Basic types +%%------------------------------------------------------------------------------ + +%% @doc All integers between `Low' and `High', bounds included. +%% `Low' and `High' must be Erlang expressions that evaluate to integers, with +%% `Low =< High'. Additionally, `Low' and `High' may have the value `inf', in +%% which case they represent minus infinity and plus infinity respectively. +%% Instances shrink towards 0 if `Low =< 0 =< High', or towards the bound with +%% the smallest absolute value otherwise. +-spec integer(extint(), extint()) -> proper_types:type(). +integer(Low, High) -> + ?BASIC([ + {env, {Low, High}}, + {generator, {typed, fun integer_gen/2}}, + {is_instance, {typed, fun integer_is_instance/2}}, + {shrinkers, [fun number_shrinker/3]} + ]). + +integer_gen(Type, Size) -> + {Low, High} = get_prop(env, Type), + proper_gen:integer_gen(Size, Low, High). + +integer_is_instance(Type, X) -> + {Low, High} = get_prop(env, Type), + is_integer(X) andalso le(Low, X) andalso le(X, High). + +number_shrinker(X, Type, S) -> + {Low, High} = get_prop(env, Type), + proper_shrink:number_shrinker(X, Low, High, S). + +%% @doc All floats between `Low' and `High', bounds included. +%% `Low' and `High' must be Erlang expressions that evaluate to floats, with +%% `Low =< High'. Additionally, `Low' and `High' may have the value `inf', in +%% which case they represent minus infinity and plus infinity respectively. +%% Instances shrink towards 0.0 if `Low =< 0.0 =< High', or towards the bound +%% with the smallest absolute value otherwise. +-spec float(extnum(), extnum()) -> proper_types:type(). +float(Low, High) -> + ?BASIC([ + {env, {Low, High}}, + {generator, {typed, fun float_gen/2}}, + {is_instance, {typed, fun float_is_instance/2}}, + {shrinkers, [fun number_shrinker/3]} + ]). + +float_gen(Type, Size) -> + {Low, High} = get_prop(env, Type), + proper_gen:float_gen(Size, Low, High). + +float_is_instance(Type, X) -> + {Low, High} = get_prop(env, Type), + is_float(X) andalso le(Low, X) andalso le(X, High). + +%% @private +-spec le(extnum(), extnum()) -> boolean(). +le(inf, _B) -> true; +le(_A, inf) -> true; +le(A, B) -> A =< B. + +%% @doc All atoms. All atoms used internally by PropEr start with a '`$'', so +%% such atoms will never be produced as instances of this type. You should also +%% refrain from using such atoms in your code, to avoid a potential clash. +%% Instances shrink towards the empty atom, ''. +-spec atom() -> proper_types:type(). +atom() -> + ?WRAPPER([ + {generator, fun proper_gen:atom_gen/1}, + {reverse_gen, fun proper_gen:atom_rev/1}, + {size_transform, fun(Size) -> erlang:min(Size,255) end}, + {is_instance, fun atom_is_instance/1} + ]). + +atom_is_instance(X) -> + is_atom(X) + %% We return false for atoms starting with '$', since these are + %% atoms used internally and never produced by the atom generator. + andalso (X =:= '' orelse hd(atom_to_list(X)) =/= $$). + +%% @doc All binaries. Instances shrink towards the empty binary, `<<>>'. +-spec binary() -> proper_types:type(). +binary() -> + ?WRAPPER([ + {generator, fun proper_gen:binary_gen/1}, + {reverse_gen, fun proper_gen:binary_rev/1}, + {is_instance, fun erlang:is_binary/1} + ]). + +%% @doc All binaries with a byte size of `Len'. +%% `Len' must be an Erlang expression that evaluates to a non-negative integer. +%% Instances shrink towards binaries of zeroes. +-spec binary(length()) -> proper_types:type(). +binary(Len) -> + ?WRAPPER([ + {env, Len}, + {generator, {typed, fun binary_len_gen/1}}, + {reverse_gen, fun proper_gen:binary_rev/1}, + {is_instance, {typed, fun binary_len_is_instance/2}} + ]). + +binary_len_gen(Type) -> + Len = get_prop(env, Type), + proper_gen:binary_len_gen(Len). + +binary_len_is_instance(Type, X) -> + Len = get_prop(env, Type), + is_binary(X) andalso byte_size(X) =:= Len. + +%% @doc All bitstrings. Instances shrink towards the empty bitstring, `<<>>'. +-spec bitstring() -> proper_types:type(). +bitstring() -> + ?WRAPPER([ + {generator, fun proper_gen:bitstring_gen/1}, + {reverse_gen, fun proper_gen:bitstring_rev/1}, + {is_instance, fun erlang:is_bitstring/1} + ]). + +%% @doc All bitstrings with a bit size of `Len'. +%% `Len' must be an Erlang expression that evaluates to a non-negative integer. +%% Instances shrink towards bitstrings of zeroes +-spec bitstring(length()) -> proper_types:type(). +bitstring(Len) -> + ?WRAPPER([ + {env, Len}, + {generator, {typed, fun bitstring_len_gen/1}}, + {reverse_gen, fun proper_gen:bitstring_rev/1}, + {is_instance, {typed, fun bitstring_len_is_instance/2}} + ]). + +bitstring_len_gen(Type) -> + Len = get_prop(env, Type), + proper_gen:bitstring_len_gen(Len). + +bitstring_len_is_instance(Type, X) -> + Len = get_prop(env, Type), + is_bitstring(X) andalso bit_size(X) =:= Len. + +%% @doc All lists containing elements of type `ElemType'. +%% Instances shrink towards the empty list, `[]'. +-spec list(ElemType::raw_type()) -> proper_types:type(). +% TODO: subtyping would be useful here (list, vector, fixed_list) +list(RawElemType) -> + ElemType = cook_outer(RawElemType), + ?CONTAINER([ + {generator, {typed, fun list_gen/2}}, + {is_instance, {typed, fun list_is_instance/2}}, + {internal_type, ElemType}, + {get_length, fun erlang:length/1}, + {split, fun lists:split/2}, + {join, fun lists:append/2}, + {get_indices, fun list_get_indices/2}, + {remove, fun proper_arith:list_remove/2}, + {retrieve, fun lists:nth/2}, + {update, fun proper_arith:list_update/3} + ]). + +list_gen(Type, Size) -> + ElemType = get_prop(internal_type, Type), + proper_gen:list_gen(Size, ElemType). + +list_is_instance(Type, X) -> + ElemType = get_prop(internal_type, Type), + list_test(X, ElemType). + +%% @doc A type that generates exactly the list `List'. Instances shrink towards +%% shorter sublists of the original list. +-spec shrink_list([term()]) -> proper_types:type(). +shrink_list(List) -> + ?CONTAINER([ + {env, List}, + {generator, {typed, fun shrink_list_gen/1}}, + {is_instance, {typed, fun shrink_list_is_instance/2}}, + {get_length, fun erlang:length/1}, + {split, fun lists:split/2}, + {join, fun lists:append/2}, + {get_indices, fun list_get_indices/2}, + {remove, fun proper_arith:list_remove/2} + ]). + +shrink_list_gen(Type) -> + get_prop(env, Type). + +shrink_list_is_instance(Type, X) -> + List = get_prop(env, Type), + is_sublist(X, List). + +-spec is_sublist([term()], [term()]) -> boolean(). +is_sublist([], _) -> true; +is_sublist(_, []) -> false; +is_sublist([H|T1], [H|T2]) -> is_sublist(T1, T2); +is_sublist(Slice, [_|T2]) -> is_sublist(Slice, T2). + +-spec list_test(proper_gen:imm_instance(), proper_types:type()) -> boolean(). +list_test(X, ElemType) -> + is_list(X) andalso lists:all(fun(E) -> is_instance(E, ElemType) end, X). + +%% @private +-spec list_get_indices(proper_gen:generator(), list()) -> [position()]. +list_get_indices(_, List) -> + lists:seq(1, length(List)). + +%% @private +%% This assumes that: +%% - instances of size S are always valid instances of size >S +%% - any recursive calls inside Gen are lazy +-spec distlist(size(), proper_gen:sized_generator(), boolean()) -> + proper_types:type(). +distlist(Size, Gen, NonEmpty) -> + ParentType = case NonEmpty of + true -> non_empty(list(Gen(Size))); + false -> list(Gen(Size)) + end, + ?SUBTYPE(ParentType, [ + {subenv, {Size, Gen, NonEmpty}}, + {generator, {typed, fun distlist_gen/1}} + ]). + +distlist_gen(Type) -> + {Size, Gen, NonEmpty} = get_prop(subenv, Type), + proper_gen:distlist_gen(Size, Gen, NonEmpty). + +%% @doc All lists of length `Len' containing elements of type `ElemType'. +%% `Len' must be an Erlang expression that evaluates to a non-negative integer. +-spec vector(length(), ElemType::raw_type()) -> proper_types:type(). +vector(Len, RawElemType) -> + ElemType = cook_outer(RawElemType), + ?CONTAINER([ + {env, Len}, + {generator, {typed, fun vector_gen/1}}, + {is_instance, {typed, fun vector_is_instance/2}}, + {internal_type, ElemType}, + {get_indices, fun vector_get_indices/2}, + {retrieve, fun lists:nth/2}, + {update, fun proper_arith:list_update/3} + ]). + +vector_gen(Type) -> + Len = get_prop(env, Type), + ElemType = get_prop(internal_type, Type), + proper_gen:vector_gen(Len, ElemType). + +vector_is_instance(Type, X) -> + Len = get_prop(env, Type), + ElemType = get_prop(internal_type, Type), + is_list(X) + andalso length(X) =:= Len + andalso lists:all(fun(E) -> is_instance(E, ElemType) end, X). + +vector_get_indices(Type, _X) -> + lists:seq(1, get_prop(env, Type)). + +%% @doc The union of all types in `ListOfTypes'. `ListOfTypes' can't be empty. +%% The random instance generator is equally likely to choose any one of the +%% types in `ListOfTypes'. The shrinking subsystem will always try to shrink an +%% instance of a type union to an instance of the first type in `ListOfTypes', +%% thus you should write the simplest case first. +-spec union(ListOfTypes::[raw_type(),...]) -> proper_types:type(). +union(RawChoices) -> + Choices = [cook_outer(C) || C <- RawChoices], + ?BASIC([ + {env, Choices}, + {generator, {typed, fun union_gen/1}}, + {is_instance, {typed, fun union_is_instance/2}}, + {shrinkers, [fun union_shrinker_1/3, fun union_shrinker_2/3]} + ]). + +union_gen(Type) -> + Choices = get_prop(env,Type), + proper_gen:union_gen(Choices). + +union_is_instance(Type, X) -> + Choices = get_prop(env, Type), + lists:any(fun(C) -> is_instance(X, C) end, Choices). + +union_shrinker_1(X, Type, S) -> + Choices = get_prop(env, Type), + proper_shrink:union_first_choice_shrinker(X, Choices, S). + +union_shrinker_2(X, Type, S) -> + Choices = get_prop(env, Type), + proper_shrink:union_recursive_shrinker(X, Choices, S). + +%% @doc A specialization of {@link union/1}, where each type in `ListOfTypes' is +%% assigned a frequency. Frequencies must be Erlang expressions that evaluate to +%% positive integers. Types with larger frequencies are more likely to be chosen +%% by the random instance generator. The shrinking subsystem will ignore the +%% frequencies and try to shrink towards the first type in the list. +-spec weighted_union(ListOfTypes::[{frequency(),raw_type()},...]) -> + proper_types:type(). +weighted_union(RawFreqChoices) -> + CookFreqType = fun({Freq,RawType}) -> {Freq,cook_outer(RawType)} end, + FreqChoices = lists:map(CookFreqType, RawFreqChoices), + Choices = [T || {_F,T} <- FreqChoices], + ?SUBTYPE(union(Choices), [ + {subenv, FreqChoices}, + {generator, {typed, fun weighted_union_gen/1}} + ]). + +weighted_union_gen(Gen) -> + FreqChoices = get_prop(subenv, Gen), + proper_gen:weighted_union_gen(FreqChoices). + +%% @private +-spec safe_union([raw_type(),...]) -> proper_types:type(). +safe_union(RawChoices) -> + Choices = [cook_outer(C) || C <- RawChoices], + subtype( + [{subenv, Choices}, + {generator, {typed, fun safe_union_gen/1}}], + union(Choices)). + +safe_union_gen(Type) -> + Choices = get_prop(subenv, Type), + proper_gen:safe_union_gen(Choices). + +%% @private +-spec safe_weighted_union([{frequency(),raw_type()},...]) -> + proper_types:type(). +safe_weighted_union(RawFreqChoices) -> + CookFreqType = fun({Freq,RawType}) -> + {Freq,cook_outer(RawType)} end, + FreqChoices = lists:map(CookFreqType, RawFreqChoices), + Choices = [T || {_F,T} <- FreqChoices], + subtype([{subenv, FreqChoices}, + {generator, {typed, fun safe_weighted_union_gen/1}}], + union(Choices)). + +safe_weighted_union_gen(Type) -> + FreqChoices = get_prop(subenv, Type), + proper_gen:safe_weighted_union_gen(FreqChoices). + +%% @doc All tuples whose i-th element is an instance of the type at index i of +%% `ListOfTypes'. Also written simply as a tuple of types. +-spec tuple(ListOfTypes::[raw_type()]) -> proper_types:type(). +tuple(RawFields) -> + Fields = [cook_outer(F) || F <- RawFields], + ?CONTAINER([ + {env, Fields}, + {generator, {typed, fun tuple_gen/1}}, + {is_instance, {typed, fun tuple_is_instance/2}}, + {internal_types, list_to_tuple(Fields)}, + {get_indices, fun tuple_get_indices/2}, + {retrieve, fun erlang:element/2}, + {update, fun tuple_update/3} + ]). + +tuple_gen(Type) -> + Fields = get_prop(env, Type), + proper_gen:tuple_gen(Fields). + +tuple_is_instance(Type, X) -> + Fields = get_prop(env, Type), + is_tuple(X) andalso fixed_list_test(tuple_to_list(X), Fields). + +tuple_get_indices(Type, _X) -> + lists:seq(1, length(get_prop(env, Type))). + +-spec tuple_update(index(), value(), tuple()) -> tuple(). +tuple_update(Index, NewElem, Tuple) -> + setelement(Index, Tuple, NewElem). + +%% @doc Tuples whose elements are all of type `ElemType'. +%% Instances shrink towards the 0-size tuple, `{}'. +-spec loose_tuple(ElemType::raw_type()) -> proper_types:type(). +loose_tuple(RawElemType) -> + ElemType = cook_outer(RawElemType), + ?WRAPPER([ + {env, ElemType}, + {generator, {typed, fun loose_tuple_gen/2}}, + {reverse_gen, {typed, fun loose_tuple_rev/2}}, + {is_instance, {typed, fun loose_tuple_is_instance/2}} + ]). + +loose_tuple_gen(Type, Size) -> + ElemType = get_prop(env, Type), + proper_gen:loose_tuple_gen(Size, ElemType). + +loose_tuple_rev(Type, X) -> + ElemType = get_prop(env, Type), + proper_gen:loose_tuple_rev(X, ElemType). + +loose_tuple_is_instance(Type, X) -> + ElemType = get_prop(env, Type), + is_tuple(X) andalso list_test(tuple_to_list(X), ElemType). + +%% @doc Singleton type consisting only of `E'. `E' must be an evaluated term. +%% Also written simply as `E'. +-spec exactly(term()) -> proper_types:type(). +exactly(E) -> + ?BASIC([ + {env, E}, + {generator, {typed, fun exactly_gen/1}}, + {is_instance, {typed, fun exactly_is_instance/2}} + ]). + +exactly_gen(Type) -> + E = get_prop(env, Type), + proper_gen:exactly_gen(E). + +exactly_is_instance(Type, X) -> + E = get_prop(env, Type), + X =:= E. + +%% @doc All lists whose i-th element is an instance of the type at index i of +%% `ListOfTypes'. Also written simply as a list of types. +-spec fixed_list(ListOfTypes::maybe_improper_list(raw_type(),raw_type()|[])) -> + proper_types:type(). +fixed_list(MaybeImproperRawFields) -> + %% CAUTION: must handle improper lists + {Fields, Internal, Len, Retrieve, Update} = + case proper_arith:cut_improper_tail(MaybeImproperRawFields) of + % TODO: have cut_improper_tail return the length and use it in test? + {ProperRawHead, ImproperRawTail} -> + HeadLen = length(ProperRawHead), + CookedHead = [cook_outer(F) || F <- ProperRawHead], + CookedTail = cook_outer(ImproperRawTail), + {{CookedHead,CookedTail}, + CookedHead ++ CookedTail, + HeadLen + 1, + fun(I,L) -> improper_list_retrieve(I, L, HeadLen) end, + fun(I,V,L) -> improper_list_update(I, V, L, HeadLen) end}; + ProperRawFields -> + LocalFields = [cook_outer(F) || F <- ProperRawFields], + {LocalFields, + LocalFields, + length(ProperRawFields), + fun lists:nth/2, + fun proper_arith:list_update/3} + end, + ?CONTAINER([ + {env, {Fields, Len}}, + {generator, {typed, fun fixed_list_gen/1}}, + {is_instance, {typed, fun fixed_list_is_instance/2}}, + {internal_types, Internal}, + {get_indices, fun fixed_list_get_indices/2}, + {retrieve, Retrieve}, + {update, Update} + ]). + +fixed_list_gen(Type) -> + {Fields, _} = get_prop(env, Type), + proper_gen:fixed_list_gen(Fields). + +fixed_list_is_instance(Type, X) -> + {Fields, _} = get_prop(env, Type), + fixed_list_test(X, Fields). + +fixed_list_get_indices(Type, _X) -> + {_, Len} = get_prop(env, Type), + lists:seq(1, Len). + +-spec fixed_list_test(proper_gen:imm_instance(), + [proper_types:type()] | {[proper_types:type()], + proper_types:type()}) -> + boolean(). +fixed_list_test(X, {ProperHead,ImproperTail}) -> + is_list(X) andalso + begin + ProperHeadLen = length(ProperHead), + proper_arith:head_length(X) >= ProperHeadLen andalso + begin + {XHead,XTail} = lists:split(ProperHeadLen, X), + fixed_list_test(XHead, ProperHead) + andalso is_instance(XTail, ImproperTail) + end + end; +fixed_list_test(X, ProperFields) -> + is_list(X) + andalso length(X) =:= length(ProperFields) + andalso lists:all(fun({E,T}) -> is_instance(E, T) end, + lists:zip(X, ProperFields)). + +%% TODO: Move these 2 functions to proper_arith? +-spec improper_list_retrieve(index(), nonempty_improper_list(value(),value()), + pos_integer()) -> value(). +improper_list_retrieve(Index, List, HeadLen) -> + case Index =< HeadLen of + true -> lists:nth(Index, List); + false -> lists:nthtail(HeadLen, List) + end. + +-spec improper_list_update(index(), value(), + nonempty_improper_list(value(),value()), + pos_integer()) -> + nonempty_improper_list(value(),value()). +improper_list_update(Index, Value, List, HeadLen) -> + case Index =< HeadLen of + %% TODO: This happens to work, but is not implied by list_update's spec. + true -> proper_arith:list_update(Index, Value, List); + false -> lists:sublist(List, HeadLen) ++ Value + end. + +%% @doc All pure functions that map instances of `ArgTypes' to instances of +%% `RetType'. The syntax `function(Arity, RetType)' is also acceptable. +-spec function(ArgTypes::[raw_type()] | arity(), RetType::raw_type()) -> + proper_types:type(). +function(Arity, RawRetType) when is_integer(Arity), Arity >= 0, Arity =< 255 -> + RetType = cook_outer(RawRetType), + ?BASIC([ + {env, {Arity, RetType}}, + {generator, {typed, fun function_gen/1}}, + {is_instance, {typed, fun function_is_instance/2}} + ]); +function(RawArgTypes, RawRetType) -> + function(length(RawArgTypes), RawRetType). + +function_gen(Type) -> + {Arity, RetType} = get_prop(env, Type), + proper_gen:function_gen(Arity, RetType). + +function_is_instance(Type, X) -> + {Arity, RetType} = get_prop(env, Type), + is_function(X, Arity) + %% TODO: what if it's not a function we produced? + andalso equal_types(RetType, proper_gen:get_ret_type(X)). + +%% @doc All Erlang terms (that PropEr can produce). For reasons of efficiency, +%% functions are never produced as instances of this type.<br /> +%% CAUTION: Instances of this type are expensive to produce, shrink and instance- +%% check, both in terms of processing time and consumed memory. Only use this +%% type if you are certain that you need it. +-spec any() -> proper_types:type(). +any() -> + AllTypes = [integer(),float(),atom(),bitstring(),?LAZY(loose_tuple(any())), + ?LAZY(list(any()))], + ?SUBTYPE(union(AllTypes), [ + {generator, fun proper_gen:any_gen/1} + ]). + + +%%------------------------------------------------------------------------------ +%% Type aliases +%%------------------------------------------------------------------------------ + +%% @equiv integer(inf, inf) +-spec integer() -> proper_types:type(). +integer() -> integer(inf, inf). + +%% @equiv integer(0, inf) +-spec non_neg_integer() -> proper_types:type(). +non_neg_integer() -> integer(0, inf). + +%% @equiv integer(1, inf) +-spec pos_integer() -> proper_types:type(). +pos_integer() -> integer(1, inf). + +%% @equiv integer(inf, -1) +-spec neg_integer() -> proper_types:type(). +neg_integer() -> integer(inf, -1). + +%% @equiv integer(Low, High) +-spec range(extint(), extint()) -> proper_types:type(). +range(Low, High) -> integer(Low, High). + +%% @equiv float(inf, inf) +-spec float() -> proper_types:type(). +float() -> float(inf, inf). + +%% @equiv float(0.0, inf) +-spec non_neg_float() -> proper_types:type(). +non_neg_float() -> float(0.0, inf). + +%% @equiv union([integer(), float()]) +-spec number() -> proper_types:type(). +number() -> union([integer(), float()]). + +%% @doc The atoms `true' and `false'. Instances shrink towards `false'. +-spec boolean() -> proper_types:type(). +boolean() -> union(['false', 'true']). + +%% @equiv integer(0, 255) +-spec byte() -> proper_types:type(). +byte() -> integer(0, 255). + +%% @equiv integer(0, 16#10ffff) +-spec char() -> proper_types:type(). +char() -> integer(0, 16#10ffff). + +%% @equiv list(any()) +-spec list() -> proper_types:type(). +list() -> list(any()). + +%% @equiv loose_tuple(any()) +-spec tuple() -> proper_types:type(). +tuple() -> loose_tuple(any()). + +%% @equiv list(char()) +-spec string() -> proper_types:type(). +string() -> list(char()). + +%% @equiv weighted_union(FreqChoices) +-spec wunion([{frequency(),raw_type()},...]) -> proper_types:type(). +wunion(FreqChoices) -> weighted_union(FreqChoices). + +%% @equiv any() +-spec term() -> proper_types:type(). +term() -> any(). + +%% @equiv union([non_neg_integer() | infinity]) +-spec timeout() -> proper_types:type(). +timeout() -> union([non_neg_integer(), 'infinity']). + +%% @equiv integer(0, 255) +-spec arity() -> proper_types:type(). +arity() -> integer(0, 255). + + +%%------------------------------------------------------------------------------ +%% QuickCheck compatibility types +%%------------------------------------------------------------------------------ + +%% @doc Small integers (bound by the current value of the `size' parameter). +%% Instances shrink towards `0'. +-spec int() -> proper_types:type(). +int() -> ?SIZED(Size, integer(-Size,Size)). + +%% @doc Small non-negative integers (bound by the current value of the `size' +%% parameter). Instances shrink towards `0'. +-spec nat() -> proper_types:type(). +nat() -> ?SIZED(Size, integer(0,Size)). + +%% @equiv integer() +-spec largeint() -> proper_types:type(). +largeint() -> integer(). + +%% @equiv float() +-spec real() -> proper_types:type(). +real() -> float(). + +%% @equiv boolean() +-spec bool() -> proper_types:type(). +bool() -> boolean(). + +%% @equiv integer(Low, High) +-spec choose(extint(), extint()) -> proper_types:type(). +choose(Low, High) -> integer(Low, High). + +%% @equiv union(Choices) +-spec elements([raw_type(),...]) -> proper_types:type(). +elements(Choices) -> union(Choices). + +%% @equiv union(Choices) +-spec oneof([raw_type(),...]) -> proper_types:type(). +oneof(Choices) -> union(Choices). + +%% @equiv weighted_union(Choices) +-spec frequency([{frequency(),raw_type()},...]) -> proper_types:type(). +frequency(FreqChoices) -> weighted_union(FreqChoices). + +%% @equiv exactly(E) +-spec return(term()) -> proper_types:type(). +return(E) -> exactly(E). + +%% @doc Adds a default value, `Default', to `Type'. +%% The default serves as a primary shrinking target for instances, while it +%% is also chosen by the random instance generation subsystem half the time. +-spec default(raw_type(), raw_type()) -> proper_types:type(). +default(Default, Type) -> + union([Default, Type]). + +%% @doc All sorted lists containing elements of type `ElemType'. +%% Instances shrink towards the empty list, `[]'. +-spec orderedlist(ElemType::raw_type()) -> proper_types:type(). +orderedlist(RawElemType) -> + ?LET(L, list(RawElemType), lists:sort(L)). + +%% @equiv function(0, RetType) +-spec function0(raw_type()) -> proper_types:type(). +function0(RetType) -> + function(0, RetType). + +%% @equiv function(1, RetType) +-spec function1(raw_type()) -> proper_types:type(). +function1(RetType) -> + function(1, RetType). + +%% @equiv function(2, RetType) +-spec function2(raw_type()) -> proper_types:type(). +function2(RetType) -> + function(2, RetType). + +%% @equiv function(3, RetType) +-spec function3(raw_type()) -> proper_types:type(). +function3(RetType) -> + function(3, RetType). + +%% @equiv function(4, RetType) +-spec function4(raw_type()) -> proper_types:type(). +function4(RetType) -> + function(4, RetType). + +%% @doc A specialization of {@link default/2}, where `Default' and `Type' are +%% assigned weights to be considered by the random instance generator. The +%% shrinking subsystem will ignore the weights and try to shrink using the +%% default value. +-spec weighted_default({frequency(),raw_type()}, {frequency(),raw_type()}) -> + proper_types:type(). +weighted_default(Default, Type) -> + weighted_union([Default, Type]). + + +%%------------------------------------------------------------------------------ +%% Additional type specification functions +%%------------------------------------------------------------------------------ + +%% @doc Overrides the `size' parameter used when generating instances of +%% `Type' with `NewSize'. Has no effect on size-less types, such as unions. +%% Also, this will not affect the generation of any internal types contained in +%% `Type', such as the elements of a list - those will still be generated +%% using the test-wide value of `size'. One use of this function is to modify +%% types to produce instances that grow faster or slower, like so: +%% ```?SIZED(Size, resize(Size * 2, list(integer()))''' +%% The above specifies a list type that grows twice as fast as normal lists. +-spec resize(size(), Type::raw_type()) -> proper_types:type(). +resize(NewSize, RawType) -> + Type = cook_outer(RawType), + case find_prop(size_transform, Type) of + {ok,Transform} -> + add_prop(size_transform, fun(_S) -> Transform(NewSize) end, Type); + error -> + add_prop(size_transform, fun(_S) -> NewSize end, Type) + end. + +%% @doc This is a predefined constraint that can be applied to random-length +%% list and binary types to ensure that the produced values are never empty. +%% +%% e.g. {@link list/0}, {@link string/0}, {@link binary/0}) +-spec non_empty(ListType::raw_type()) -> proper_types:type(). +non_empty(RawListType) -> + ?SUCHTHAT(L, RawListType, L =/= [] andalso L =/= <<>>). + +%% @doc Creates a new type which is equivalent to `Type', but whose instances +%% are never shrunk by the shrinking subsystem. +-spec noshrink(Type::raw_type()) -> proper_types:type(). +noshrink(RawType) -> + add_prop(noshrink, true, cook_outer(RawType)). + +%% @doc Associates the atom key `Parameter' with the value `Value' while +%% generating instances of `Type'. +-spec with_parameter(atom(), value(), Type::raw_type()) -> proper_types:type(). +with_parameter(Parameter, Value, RawType) -> + with_parameters([{Parameter,Value}], RawType). + +%% @doc Similar to {@link with_parameter/3}, but accepts a list of +%% `{Parameter, Value}' pairs. +-spec with_parameters([{atom(),value()}], Type::raw_type()) -> + proper_types:type(). +with_parameters(PVlist, RawType) -> + Type = cook_outer(RawType), + case find_prop(parameters, Type) of + {ok,Params} when is_list(Params) -> + append_list_to_prop(parameters, PVlist, Type); + error -> + add_prop(parameters, PVlist, Type) + end. + +%% @doc Returns the value associated with `Parameter', or `Default' in case +%% `Parameter' is not associated with any value. +-spec parameter(atom(), value()) -> value(). +parameter(Parameter, Default) -> + Parameters = + case erlang:get('$parameters') of + undefined -> []; + List -> List + end, + proplists:get_value(Parameter, Parameters, Default). + +%% @equiv parameter(Parameter, undefined) +-spec parameter(atom()) -> value(). +parameter(Parameter) -> + parameter(Parameter, undefined). |