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%
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%  Copyright 1998-2021 Paulo Moura <pmoura@logtalk.org>
%  SPDX-License-Identifier: Apache-2.0
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%      http://www.apache.org/licenses/LICENSE-2.0
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:- set_logtalk_flag(undefined_predicates, silent).


:- object(tests,
	extends(lgtunit)).

	:- info([
		version is 1:1:0,
		author is 'Paulo Moura',
		date is 2019-03-29,
		comment is 'Unit tests for the coinductive/1 built-in directive.'
	]).

	% test all possible syntaxes for the directive

	:- public(a/1).
	:- coinductive(a/1).

	test(coinductive_1_01) :-
		predicate_property(a(_), coinductive(Template)),
		Template == a(+).


	:- public(b//0).
	:- coinductive(b//0).

	test(coinductive_1_02) :-
		predicate_property(b(_,_), coinductive(Template)),
		Template == b(+,+).

	:- public(c/2).
	:- coinductive(c(+, -)).

	test(coinductive_1_03) :-
		predicate_property(c(_, _), coinductive(Template)),
		Template == c(+, -).

	% calls to predicates declared coinductive but not defined
	% must fail instead of throwing an existence error

	:- coinductive(d/3).

	test(coinductive_1_04) :-
		\+ d(_, _, _).

:- end_object.
