akbasic/tests/graphics_verbs.c

/**
 * @file graphics_verbs.c
 * @brief Tests the group G verbs against the recording mock backend.
 *
 * These verbs emit nothing a golden file can compare, so the assertions are on
 * the call log: what reached the device, in what order, with what geometry and
 * what color. Running a real BASIC line rather than calling the handler directly
 * is deliberate -- it exercises the dispatch-table row and the parse handler as
 * well, which is where an added verb is most likely to be wrong.
 */

#include <string.h>

#include <akbasic/error.h>
#include <akbasic/graphics.h>
#include <akbasic/runtime.h>

#include "harness.h"
#include "mockdevice.h"
#include "testutil.h"

/** @brief Bring up a runtime with the mock devices attached and a program loaded. */
static akerr_ErrorContext AKERR_NOIGNORE *run_program(const char *source)
{
    PREPARE_ERROR(errctx);

    PASS(errctx, harness_start(NULL));
    mock_devices_init();
    PASS(errctx, akbasic_runtime_set_devices(&HARNESS_RUNTIME, &MOCK_GRAPHICS,
					     &MOCK_AUDIO, &MOCK_INPUT));
    PASS(errctx, akbasic_runtime_load(&HARNESS_RUNTIME, source));
    PASS(errctx, akbasic_runtime_start(&HARNESS_RUNTIME, AKBASIC_MODE_RUN));
    PASS(errctx, akbasic_runtime_run(&HARNESS_RUNTIME, 0));
    SUCCEED_RETURN(errctx);
}

/** @brief The white of palette index 2, which most of these draw with. */
#define WHITE "#ffffff"
/** @brief The red of palette index 3. */
#define RED "#883932"

/**
 * @brief A single DRAW coordinate pair plots a point; two or more draw a
 *        polyline; none at all plots wherever LOCATE left the cursor.
 */
static void test_draw(void)
{
    TEST_REQUIRE_OK(run_program("10 DRAW 1, 10, 20\n"));
    TEST_REQUIRE_STR(MOCK.log, "point 10.0,20.0 " WHITE "\n");
    harness_stop();

    TEST_REQUIRE_OK(run_program("10 DRAW 1, 0, 0 TO 10, 0 TO 10, 10\n"));
    TEST_REQUIRE_STR(MOCK.log,
		     "line 0.0,0.0-10.0,0.0 " WHITE "\n"
		     "line 10.0,0.0-10.0,10.0 " WHITE "\n");
    harness_stop();

    /* LOCATE moves the pixel cursor; a bare DRAW plots it. */
    TEST_REQUIRE_OK(run_program("10 LOCATE 33, 44\n20 DRAW 1\n"));
    TEST_REQUIRE_STR(MOCK.log, "point 33.0,44.0 " WHITE "\n");
    harness_stop();

    /* An odd number of coordinates is a typo, not half a line. */
    TEST_REQUIRE_OK(harness_start(NULL));
    mock_devices_init();
    TEST_REQUIRE_OK(akbasic_runtime_set_devices(&HARNESS_RUNTIME, &MOCK_GRAPHICS, NULL, NULL));
    TEST_REQUIRE_OK(akbasic_runtime_load(&HARNESS_RUNTIME, "10 DRAW 1, 5\n"));
    TEST_REQUIRE_OK(akbasic_runtime_start(&HARNESS_RUNTIME, AKBASIC_MODE_RUN));
    TEST_REQUIRE_OK(akbasic_runtime_run(&HARNESS_RUNTIME, 0));
    TEST_REQUIRE(strstr(HARNESS_OUTPUT, "X,Y pairs") != NULL,
		 "an odd coordinate count should be refused, got \"%s\"", HARNESS_OUTPUT);
    harness_stop();
}

/** @brief COLOR rebinds a source, and every drawing verb follows the rebinding. */
static void test_color(void)
{
    TEST_REQUIRE_OK(run_program("10 COLOR 1, 3\n20 DRAW 1, 1, 1\n"));
    TEST_REQUIRE_STR(MOCK.log, "point 1.0,1.0 " RED "\n");
    harness_stop();

    /* Both arguments are range-checked, and BASIC counts colors from 1. */
    TEST_REQUIRE_OK(run_program("10 COLOR 9, 3\n"));
    TEST_REQUIRE(strstr(HARNESS_OUTPUT, "COLOR source 9") != NULL,
		 "an out-of-range source should be refused, got \"%s\"", HARNESS_OUTPUT);
    harness_stop();

    TEST_REQUIRE_OK(run_program("10 COLOR 1, 0\n"));
    TEST_REQUIRE(strstr(HARNESS_OUTPUT, "COLOR 0") != NULL,
		 "color 0 should be refused, got \"%s\"", HARNESS_OUTPUT);
    harness_stop();
}

/** @brief An unrotated BOX is a rectangle; a rotated one is four lines. */
static void test_box(void)
{
    TEST_REQUIRE_OK(run_program("10 BOX 1, 0, 0, 10, 10\n"));
    TEST_REQUIRE_STR(MOCK.log, "rect 0.0,0.0-10.0,10.0 " WHITE "\n");
    harness_stop();

    /*
     * Rotated 90 degrees about its own center, a square lands back on itself --
     * same four edges, walked from a different starting corner. That is the
     * assertion worth making, because it pins the rotation *origin*: rotating
     * about the coordinate origin instead of the box's center would put the
     * square somewhere else entirely, and rotating about a corner would tilt it.
     *
     * The -0.0 is real and harmless: cos(pi/2) is not exactly zero, so one
     * coordinate lands on negative zero, which compares equal to zero everywhere
     * it matters and only shows up because the mock prints it.
     */
    TEST_REQUIRE_OK(run_program("10 BOX 1, 0, 0, 10, 10, 90\n"));
    TEST_REQUIRE_STR(MOCK.log,
		     "line 10.0,-0.0-10.0,10.0 " WHITE "\n"
		     "line 10.0,10.0-0.0,10.0 " WHITE "\n"
		     "line 0.0,10.0-0.0,0.0 " WHITE "\n"
		     "line 0.0,0.0-10.0,-0.0 " WHITE "\n");
    harness_stop();
}

/** @brief CIRCLE is a polygon of arc-increment segments, and closes. */
static void test_circle(void)
{
    int segments = 0;
    const char *cursor = NULL;

    /* 360 degrees at 90 per segment is four lines, whatever the radius. */
    TEST_REQUIRE_OK(run_program("10 CIRCLE 1, 50, 50, 10, 10, 0, 360, 0, 90\n"));
    for ( cursor = MOCK.log; (cursor = strstr(cursor, "line ")) != NULL; cursor += 5 ) {
	segments += 1;
    }
    TEST_REQUIRE_INT(segments, 4);
    /* The first vertex is directly above the center, as BASIC 7.0 starts it. */
    TEST_REQUIRE(strncmp(MOCK.log, "line 50.0,40.0-", 15) == 0,
		 "CIRCLE should start at the top of the circle, got \"%.30s\"", MOCK.log);
    harness_stop();

    /* A negative radius and a zero increment are both refusals, not loops. */
    TEST_REQUIRE_OK(run_program("10 CIRCLE 1, 50, 50, -5\n"));
    TEST_REQUIRE(strstr(HARNESS_OUTPUT, "radius") != NULL,
		 "a negative radius should be refused, got \"%s\"", HARNESS_OUTPUT);
    harness_stop();

    TEST_REQUIRE_OK(run_program("10 CIRCLE 1, 50, 50, 10, 10, 0, 360, 0, 0\n"));
    TEST_REQUIRE(strstr(HARNESS_OUTPUT, "increment") != NULL,
		 "a zero arc increment should be refused, got \"%s\"", HARNESS_OUTPUT);
    harness_stop();
}

/**
 * @brief PAINT reports a partial fill rather than letting it pass as success.
 *
 * The device gives up when its span stack runs out, having filled some of the
 * region. A program that cannot tell that happened has no way to recover, so the
 * error is the feature.
 */
static void test_paint(void)
{
    TEST_REQUIRE_OK(run_program("10 PAINT 1, 5, 5\n"));
    TEST_REQUIRE_STR(MOCK.log, "paint 5,5 " WHITE "\n");
    harness_stop();

    TEST_REQUIRE_OK(harness_start(NULL));
    mock_devices_init();
    MOCK.paint_exhausts = true;
    TEST_REQUIRE_OK(akbasic_runtime_set_devices(&HARNESS_RUNTIME, &MOCK_GRAPHICS, NULL, NULL));
    TEST_REQUIRE_OK(akbasic_runtime_load(&HARNESS_RUNTIME, "10 PAINT 1, 5, 5\n"));
    TEST_REQUIRE_OK(akbasic_runtime_start(&HARNESS_RUNTIME, AKBASIC_MODE_RUN));
    TEST_REQUIRE_OK(akbasic_runtime_run(&HARNESS_RUNTIME, 0));
    TEST_REQUIRE(strstr(HARNESS_OUTPUT, "only part of the region") != NULL,
		 "a partial fill should be reported, got \"%s\"", HARNESS_OUTPUT);
    harness_stop();
}

/** @brief SCALE maps user coordinates onto the 320x200 space, and only then. */
static void test_scale(void)
{
    /* Off by default: a coordinate passes through untouched. */
    TEST_REQUIRE_OK(run_program("10 DRAW 1, 160, 100\n"));
    TEST_REQUIRE_STR(MOCK.log, "point 160.0,100.0 " WHITE "\n");
    harness_stop();

    /* On, with the 7.0 default maxima: the middle of the user space is the
       middle of the screen. */
    TEST_REQUIRE_OK(run_program("10 SCALE 1\n20 DRAW 1, 1023, 1023\n"));
    TEST_REQUIRE_STR(MOCK.log, "point 320.0,200.0 " WHITE "\n");
    harness_stop();

    TEST_REQUIRE_OK(run_program("10 SCALE 1, 640, 400\n20 DRAW 1, 320, 200\n"));
    TEST_REQUIRE_STR(MOCK.log, "point 160.0,100.0 " WHITE "\n");
    harness_stop();

    TEST_REQUIRE_OK(run_program("10 SCALE 1, 0, 400\n"));
    TEST_REQUIRE(strstr(HARNESS_OUTPUT, "positive") != NULL,
		 "a zero SCALE maximum should be refused, got \"%s\"", HARNESS_OUTPUT);
    harness_stop();
}

/** @brief GRAPHIC records the mode, clears on request and refuses a bad mode. */
static void test_graphic(void)
{
    TEST_REQUIRE_OK(run_program("10 GRAPHIC 1, 1\n"));
    TEST_REQUIRE_STR(MOCK.log, "clear #000000\n");
    TEST_REQUIRE_INT(HARNESS_RUNTIME.gfx.mode, 1);
    harness_stop();

    /* Without the clear argument nothing reaches the device. */
    TEST_REQUIRE_OK(run_program("10 GRAPHIC 1\n"));
    TEST_REQUIRE_STR(MOCK.log, "");
    harness_stop();

    /* GRAPHIC CLR drops the saved shapes and resets the whole state. */
    TEST_REQUIRE_OK(run_program("10 COLOR 1, 3\n20 GRAPHIC 5\n"));
    TEST_REQUIRE_STR(MOCK.log, "freeshapes\n");
    TEST_REQUIRE_INT(HARNESS_RUNTIME.gfx.source[1], 2);
    harness_stop();

    TEST_REQUIRE_OK(run_program("10 GRAPHIC 9\n"));
    TEST_REQUIRE(strstr(HARNESS_OUTPUT, "GRAPHIC mode 9") != NULL,
		 "an out-of-range mode should be refused, got \"%s\"", HARNESS_OUTPUT);
    harness_stop();
}

/** @brief SSHAPE stores a handle a later GSHAPE can use, and only that. */
static void test_shapes(void)
{
    TEST_REQUIRE_OK(run_program("10 SSHAPE A$, 0, 0, 8, 8\n20 GSHAPE A$, 32, 32\n"));
    TEST_REQUIRE_STR(MOCK.log, "save 0,0-8,8 -> 0\npaste 0 at 32.0,32.0\n");
    harness_stop();

    /*
     * The string is opaque but not magic: a string that did not come from SSHAPE
     * has to be refused, or GSHAPE parses whatever digits it finds and pastes
     * some unrelated slot.
     */
    TEST_REQUIRE_OK(run_program("10 A$ = \"5\"\n20 GSHAPE A$, 0, 0\n"));
    TEST_REQUIRE(strstr(HARNESS_OUTPUT, "did not come from SSHAPE") != NULL,
		 "a hand-written shape string should be refused, got \"%s\"", HARNESS_OUTPUT);
    harness_stop();

    /* A numeric variable is the wrong type for either verb. */
    TEST_REQUIRE_OK(run_program("10 SSHAPE A#, 0, 0, 8, 8\n"));
    TEST_REQUIRE(strstr(HARNESS_OUTPUT, "string variable") != NULL,
		 "SSHAPE into a number should be refused, got \"%s\"", HARNESS_OUTPUT);
    harness_stop();
}

/**
 * @brief Every verb that needs a device says so by name when it has none.
 *
 * This is the standalone driver's situation, so it is the common path. COLOR,
 * LOCATE and SCALE are excluded on purpose: they only touch interpreter state
 * and must keep working before a host has lent the script a renderer.
 */
static void test_no_device(void)
{
    TEST_REQUIRE_OK(harness_start(NULL));
    TEST_REQUIRE_OK(akbasic_runtime_load(&HARNESS_RUNTIME,
					 "10 COLOR 1, 3\n"
					 "20 LOCATE 5, 5\n"
					 "30 SCALE 1\n"
					 "40 DRAW 1, 1, 1\n"));
    TEST_REQUIRE_OK(akbasic_runtime_start(&HARNESS_RUNTIME, AKBASIC_MODE_RUN));
    TEST_REQUIRE_OK(akbasic_runtime_run(&HARNESS_RUNTIME, 0));
    TEST_REQUIRE(strstr(HARNESS_OUTPUT, "DRAW needs a graphics device") != NULL,
		 "DRAW without a device should name itself, got \"%s\"", HARNESS_OUTPUT);
    TEST_REQUIRE(strstr(HARNESS_OUTPUT, "COLOR") == NULL,
		 "COLOR should not need a device, got \"%s\"", HARNESS_OUTPUT);
    TEST_REQUIRE_INT(HARNESS_RUNTIME.gfx.source[1], 3);
    TEST_REQUIRE_FEQ(HARNESS_RUNTIME.gfx.x, 5.0);
    TEST_REQUIRE(HARNESS_RUNTIME.gfx.scaling, "SCALE should not need a device");
    harness_stop();
}

int main(void)
{
    test_draw();
    test_color();
    test_box();
    test_circle();
    test_paint();
    test_scale();
    test_graphic();
    test_shapes();
    test_no_device();
    return akbasic_test_failures;
}