judge-prolog

A judge for the Prolog language.

Format of the QuickCheck tests

QuickCheck testfiles should be named with a name ending in .qc.pl. The name before the extension will be used as tabname.

All tests must have a name starting with prop_. There should be at least one blank line separating the definition from other things. A property must not contain empty lines in its definition (you may use comments to fill the space). Tests may contain comments. Comments within the test will be shown to the student, comments outside it wil not.

prop_reverse_twice(L:list(integer)) :-
    % This comment is shown to students
    my_reverse(L, R),
    my_reverse(R, L).

Format of PLUnit testfiles

PLUnit testfiles should be named with a name ending in .unit.pl. The name before the extension will be used as tabname.

The testfile will be split up into the parts between the tags :- begin_tests(...). and :- end_tests(...).. All the lines specified before the begin_tests and not in another part can be used.

:- consult(database).

:- begin_tests(groupname).
test(name_of_the_test) :- clause(largest(A,B,A),true).
test(name_of_an_other_test) :- clause(largest(A,B,A),true).
:- end_tests(groupname).

Regular PLUnit can be used

Form check

The form check checks the form of submissions. This is basically a linter.

Test specification

It is not driven by a test file, but by the exercise configuration. Following keys can be inclused in the evaluation directive:

• cutallowed: A boolean value indicationg if cuts are allowed (default false)
• predefined: List of predefined predicates in Name/Arity form, if this is set, check:check will be executed (may be the empty list)

The checkCheat test is always executed, it looks for ocurrences of dodonaevaluate and marks them as erronous.

example config

...
 "evaluation":{
    "predefined" : ["word/8"],
    "cutallowed": false
 },
...

Format of Simple Test testfiles

Compares the output (that is true/false) of the students predicates with that of a supplied correct solution.

Test specification

Test files ending in .simple.pl will automatically be be executed by this file. Such a test file should be a module that exports one predicate: test/6. The form is:

%- consult public "database.pl".
:- module(dodonaevaluate, [tests/6]).

% ...

tests("markdown name",dodonaevaluate:thepredicate,thepredicate,true,10000, L) :-
    Pers = [waldo,odlaw,swi,wilma,whitebeard,woof,watchers],
    setof([X,Y],(member(X,Pers),member(Y,Pers)),L).

The test/6 predicate has 6 arguments

1. The name, a string (double quotes), that is rendered as markdown
2. The functor name of a correct implementation (mostly of the form dodonaevaluate:....)
3. The functor name of the student implementation
4. A Boolean value indicating whether cuts are allowed (does not work properly yet)
5. An inference limit
6. A list of argument lists
   • Example for a one argument predicate : [[1],[2],[3]]
   • Example for a two argument predicate : [[1,a],[2,a],[3,a]]
   • Example for a one argument predicate that takes lists : [[[1,a]],[[2,a,9,8]],[[3,a,4]]

To make files available to both the user and test code, use one of the following lines

%- consult public "file.pl".
%- consult private "file.pl".
%- consult public ["file1.pl","file2.pl"].
%- consult private ["file1.pl","file2.pl"].

Implementation

The prolog checker code is contained in simpletest/checker.pl. It is loaded together with the student code as follows, with a copy of the workspace folder as workspace and dotests as goals for swipl.

:- use_module("{judgePath}/simpletest/checker.pl").
:- consult("/mnt/.../submission/submission.pl").
:- use_module("/mnt/.../evaluation/.....simple.pl").

The results stored in workspace/results.json are then consulted to build the feedback table

Todos

• Using the partial format
• make text below clearer