akbasic/tests/known_reference_defects.c

/**
 * @file known_reference_defects.c
 * @brief Asserts the *correct* contract for defects carried over from the reference.
 *
 * Registered in AKBASIC_KNOWN_FAILING_TESTS, so CTest expects it to fail. Every
 * assertion here states what the interpreter *should* do, not what it currently
 * does -- pinning current-but-wrong behaviour would turn the eventual fix into a
 * test failure.
 *
 * When one of these is fixed, this test starts passing and CTest reports
 * "unexpectedly passed". That is the cue to split the fixed assertion out into
 * the corresponding suite in AKBASIC_TESTS and strike the item from TODO.md
 * section 12.
 */

#include "harness.h"

int main(void)
{
    akbasic_ASTLeaf *leaf = NULL;
    akbasic_Value *out = NULL;
    char rendered[AKBASIC_MAX_STRING_LENGTH];

    TEST_REQUIRE_OK(harness_start(NULL));

    /*
     * 12.12 -- subtraction stops after one operator, so `1 - 2 - 3` parses as
     * `1 - 2` and abandons the rest of the line. It should fold left, the way
     * addition does.
     */
    TEST_REQUIRE_OK(harness_parse("A# = 1 - 2 - 3", &leaf));
    TEST_REQUIRE_OK(akbasic_leaf_to_string(leaf, rendered, sizeof(rendered)));
    TEST_REQUIRE_STR(rendered, "( A# (- (- 1 2) 3))");

    /*
     * 12.13 -- a unary-minus argument inflates the arity count, because the
     * counter walks .right and a unary leaf keeps its operand there. ABS(-9)
     * should be one argument.
     */
    TEST_REQUIRE_OK(akbasic_environment_zero(HARNESS_RUNTIME.environment));
    TEST_REQUIRE_OK(harness_parse("A# = ABS(-9)", &leaf));
    TEST_REQUIRE_OK(akbasic_runtime_evaluate(&HARNESS_RUNTIME, leaf, &out));
    TEST_REQUIRE_INT(out->intval, 9);

    /*
     * 12.14 -- a comparison operator in the final column of a line is dropped,
     * because matchNextChar returns without setting a token type when it cannot
     * peek past the end.
     */
    TEST_REQUIRE_OK(akbasic_scanner_scan(&HARNESS_RUNTIME, "A# =", NULL, 0));
    TEST_REQUIRE_INT(HARNESS_RUNTIME.environment->nexttoken, 2);

    /*
     * 12.15 -- hex literals do not survive the scanner. matchNumber lets 'x'
     * through but not the digits after it, so the parser's base-16 branch is
     * unreachable.
     */
    TEST_REQUIRE_OK(akbasic_scanner_scan(&HARNESS_RUNTIME, "PRINT 0xff", NULL, 0));
    TEST_REQUIRE_STR(HARNESS_RUNTIME.environment->tokens[1].lexeme, "0xff");

    /*
     * 12.16 -- "Reserved word in variable name" never fires, because the lexeme
     * still carries its type suffix when the verb table is searched. PRINT$
     * should be refused as a variable name.
     */
    HARNESS_RUNTIME.hasError = false;
    TEST_REQUIRE_OK(akbasic_scanner_scan(&HARNESS_RUNTIME, "PRINT$ = 1", NULL, 0));
    TEST_REQUIRE(HARNESS_RUNTIME.hasError, "PRINT$ should be refused as a variable name");

    /*
     * 12.10 -- a leading zero selects base 8, so `PRINT 010` prints 8 and
     * `PRINT 08` will not parse. Commodore BASIC has no octal literals.
     */
    TEST_REQUIRE_OK(akbasic_environment_zero(HARNESS_RUNTIME.environment));
    TEST_REQUIRE_OK(harness_parse("A# = 010", &leaf));
    TEST_REQUIRE_OK(akbasic_runtime_evaluate(&HARNESS_RUNTIME, leaf, &out));
    TEST_REQUIRE_INT(out->intval, 10);

    harness_stop();
    return akbasic_test_failures;
}