Tests for when/2 and solved bug

src/lib/when.pl

@@ -9,6 +9,9 @@ Provides the predicate `when/2`.
 :- use_module(library(lists)).
 :- use_module(library(lambda)).
 
+:- use_module(library(format)).
+:- use_module(library(debug)).
+
 :- attribute when_list/1.
 
 :- meta_predicate(when(+, 0)).
@@ -51,7 +54,7 @@ remove_goal([G0|G0s], Goal, Goals) :-
     (   G0 == Goal ->
         remove_goal(G0s, Goal, Goals)
     ;   Goals = [G0|Goals1],
-        remove_goal(G0, Goal, Goals1)
+        remove_goal(G0s, Goal, Goals1)
     ).
 
 vars_remove_goal(Vars, Goal) :-

src/tests/when.pl

@@ -0,0 +1,145 @@
+/**/
+
+:- use_module(library(format)).
+:- use_module(library(dcgs)).
+:- use_module(library(lists)).
+:- use_module(library(debug)).
+:- use_module(library(atts)).
+
+:- use_module(library(when)).
+
+test("condition true before ground/1",(
+    A = 1,
+    when(ground(A), Run = true),
+    Run == true
+)).
+
+test("condition true before nonvar/1",(
+    A = a(_),
+    when(nonvar(A), Run = true),
+    Run == true
+)).
+
+test("condition true before ','/2",(
+    A = 1,
+    B = a(_),
+    when((ground(A), nonvar(B)), Run = true),
+    Run == true
+)).
+
+test("condition true before (;)/2",(
+    A = 1,
+    when((ground(A) ; nonvar(_)), Run1 = true),
+    Run1 == true,
+
+    B = a(_),
+    when((ground(_) ; nonvar(B)), Run2 = true),
+    Run2 == true
+)).
+
+test("condition true after ground/1",(
+    when(ground(A), Run = true),
+    var(Run),
+    A = 1,
+    Run == true
+)).
+
+test("condition true after nonvar/1",(
+    when(nonvar(A), Run = true),
+    var(Run),
+    A = a(_),
+    Run == true
+)).
+
+test("condition true after ','/2",(
+    when((ground(A), nonvar(B)), Run = true),
+    var(Run),
+    A = 1,
+    var(Run),
+    B = a(_),
+    Run == true
+)).
+
+test("condition true after (;)/2",(
+    when((ground(A) ; nonvar(_)), Run1 = true),
+    var(Run1),
+    A = 1,
+    Run1 == true,
+
+    when((ground(_) ; nonvar(B)), Run2 = true),
+    var(Run2),
+    B = a(_),
+    Run2 == true
+)).
+
+test("multiple when/2 on same variable",(
+    when(nonvar(A), Run1 = true),
+    when(ground(A), Run2 = true),
+    var(Run1), var(Run2),
+    A = a(B),
+    Run1 == true, var(Run2),
+    B = 1,
+    Run2 == true
+)).
+
+main :-
+    findall(test(Name, Goal), test(Name, Goal), Tests),
+    run_tests(Tests, Failed),
+    show_failed(Failed),
+    halt.
+
+main_quiet :-
+    findall(test(Name, Goal), test(Name, Goal), Tests),
+    run_tests_quiet(Tests, Failed),
+    (   Failed = [] ->
+        format("All tests passed", [])
+    ;   format("Some tests failed", [])
+    ),
+    halt.
+
+portray_failed_([]) --> [].
+portray_failed_([F|Fs]) -->
+    "\"", F, "\"",  "\n", portray_failed_(Fs).
+
+portray_failed([]) --> [].
+portray_failed([F|Fs]) -->
+    "\n", "Failed tests:", "\n", portray_failed_([F|Fs]).
+
+show_failed(Failed) :-
+    phrase(portray_failed(Failed), F),
+    format("~s", [F]).
+
+run_tests([], []).
+run_tests([test(Name, Goal)|Tests], Failed) :-
+    format("Running test \"~s\"~n", [Name]),
+    (   call(Goal) ->
+        Failed = Failed1
+    ;   format("Failed test \"~s\"~n", [Name]),
+        Failed = [Name|Failed1]
+    ),
+    run_tests(Tests, Failed1).
+
+run_tests_quiet([], []).
+run_tests_quiet([test(Name, Goal)|Tests], Failed) :-
+    (   call(Goal) ->
+        Failed = Failed1
+    ;   Failed = [Name|Failed1]
+    ),
+    run_tests_quiet(Tests, Failed1).
+
+assert_p(A, B) :-
+    phrase(portray_clause_(A), Portrayed),
+    phrase((B, ".\n"), Portrayed).
+
+call_residual_goals(Goal, ResidualGoals) :-
+    call_residue_vars(Goal, Vars),
+    variables_residual_goals(Vars, ResidualGoals).
+
+variables_residual_goals(Vars, Goals) :-
+    phrase(variables_residual_goals(Vars), Goals).
+
+variables_residual_goals([]) --> [].
+variables_residual_goals([Var|Vars]) -->
+    dif_:attribute_goals(Var),
+    variables_residual_goals(Vars).
+

tests/scryer/cli/src_tests/when_tests.stdout

@@ -0,0 +1 @@
+All tests passed

tests/scryer/cli/src_tests/when_tests.toml

@@ -0,0 +1 @@
+args = ["-f", "--no-add-history", "src/tests/when.pl", "-f", "-g", "main_quiet"]