Either misunderstanding or bug. When load_files/2 with no imports used with load_test_files/1

Help! Predicate
1

Currently running SWI-Prolog (threaded, 64 bits, version 8.3.28-20-g6f8a68f2b)

Problem: Using load_files/2 with the option imports([]) and directive :- load_test_files([]). and predicate of same name in loaded file.

  • works as expected
          if the file being loaded does not have the directive :- load_test_files([]).
  • throws error - No permission to redefine imported_procedure
          if the file being loaded has the directive :- load_test_files([]).

My thought is that the addition of :- load_test_files([]). when none of the predicates are being imported because of imports([]) should not cause an error.

Minimal reproduceable example.

All five files are in the same directory.

File: my_app.pl

:- module(my_app,
    [
        load_check_with_tests_loaded/0,
        load_check_without_tests_loaded/0,
        my_predicate/1
    ]).

load_check_with_tests_loaded :-
    load_files(my_module_with_tests_loaded,[imports([])]).

load_check_without_tests_loaded :-
    load_files(my_module_without_tests_loaded,[imports([])]).

my_predicate(Result) :-
    Result = 'Hello from my_app.'.

File: my_module_with_tests_loaded.pl

:- module(my_module_with_tests_loaded,
    [
        my_predicate/1
    ]).

:- load_test_files([]).

my_predicate(Result) :-
    Result = 'Hello from my_module_with_tests_loaded.'.

File: my_module_with_tests_loaded.plt

:- begin_tests(my_tests_with_tests_loaded).

:- use_module(my_module_with_tests_loaded).

test(hello) :-
    my_predicate('Hello example').

:- end_tests(my_tests_with_tests_loaded).

File: my_module_without_tests_loaded.pl

:- module(my_module_without_tests_loaded,
    [
        my_predicate/1
    ]).

my_predicate(Result) :-
    Result = 'Hello from my_module_without_tests_loaded.'.

File: my_module_withpit_tests_loaded.plt

:- begin_tests(my_test_without_tests_loaded).

:- use_module(my_module_without_tests_loaded).

test(hello) :-
    my_predicate('Hello example').

:- end_tests(my_test_without_tests_loaded).

Example run.

Welcome to SWI-Prolog (threaded, 64 bits, version 8.3.28-20-g6f8a68f2b)
SWI-Prolog comes with ABSOLUTELY NO WARRANTY. This is free software.
Please run ?- license. for legal details.

For online help and background, visit https://www.swi-prolog.org
For built-in help, use ?- help(Topic). or ?- apropos(Word).

?- working_directory(_,'C:/Users/Groot').
true.

?- [my_app].
true.

?- load_check_without_tests_loaded.
true.

?- load_check_with_tests_loaded.
ERROR: c:/users/groot/my_module_with_tests_loaded.pl:25:
ERROR:    No permission to redefine imported_procedure `my_app:my_predicate/1' % ` to rebalance 
true.

Just to show that skipping the check load_check_without_tests_loaded also creates the error.

Welcome to SWI-Prolog (threaded, 64 bits, version 8.3.28-20-g6f8a68f2b)
SWI-Prolog comes with ABSOLUTELY NO WARRANTY. This is free software.
Please run ?- license. for legal details.

For online help and background, visit https://www.swi-prolog.org
For built-in help, use ?- help(Topic). or ?- apropos(Word).

?- working_directory(_,'C:/Users/Groot').
true.

?- [my_app].
true.

?- load_check_with_tests_loaded.
ERROR: c:/users/groot/my_module_with_tests_loaded.pl:25:
ERROR:    No permission to redefine imported_procedure `my_app:my_predicate/1' % ` to rebalance 
true.

EDIT

Here is a workaround which just removes the directive from the source code before the source code is loaded.

asserta((system:term_expansion((:-load_test_files(Options)),'')),Ref),
load_files(some_source_file,[imports([])]),
erase(Ref)