ww/test/wcc/817_arr_cap_reject.c

/*
 * 817_arr_cap_reject — a fixed-size array has NO capacity word; `.cap` on an
 * array is INVALID ww and BOTH stages must LOUDLY REJECT at check time
 * (GAP-A.cap, task #12; drew ruling .ai/drew-gapa-ptr-ruling.md). `.len`
 * (GAP-A.len, 7b0e09e) AND `.ptr` (≡ &A[0], the sanctioned ww backing-
 * pointer spelling, task #13 divergence-record) stay VALID on an array —
 * only `.cap` is rejected.
 *
 * The bug (each stage misbehaved DIFFERENTLY on the same invalid construct,
 * hence both-stage):
 *   - cstage check.c typed `.cap` on a TY_ARRAY as i32 → cgen then hard-
 *     rejected with a generic "unsupported field-read shape" (loud but at
 *     the WRONG layer, vague message).
 *   - wwstage check.ww stamped `.cap` → cgen link-error (def-global
 *     `A.cap` → w6l undefined 'cap') or SILENT garbage (local `a.cap`→30).
 *
 * The fix (BOTH checkers, one `.cap`-on-array gate each, byte-identical
 * diagnostic body): reject early with "no field 'cap' on a fixed-size array
 * (arrays have no capacity; use .len)". Checker-only: the reject makes the
 * buggy cgen `.cap` array paths unreachable (close by construction).
 *
 * Mutation-sanity: the genuinely-silent pre-fix case is wwstage's LOCAL
 * .cap, which BUILT and returned garbage (30) — neg_local_cap is the row
 * with real mutation power (built-ok pre-fix → caught here). The other
 * neg rows were already loud pre-fix but at the WRONG layer (cstage cgen
 * vague-reject on use; wwstage global link-error); this commit converges
 * all of them onto one early checker diagnostic.
 *
 *   neg row          | shape                                  | gate
 *   -----------------+----------------------------------------+----------
 *   neg_local_cap    | local [3]int, a.cap                     | build FAIL
 *   neg_def_cap      | def A:[3]int, A.cap                     | build FAIL
 *   neg_let_glob_cap | let G:[3]int (module), G.cap            | build FAIL
 *   neg_infer_cap    | def A:[_]int, A.cap (#11 infer path)    | build FAIL
 *
 *   pos row          | shape                                  | want
 *   -----------------+----------------------------------------+------
 *   pos_local_len    | local [3]int, a.len                     | 3
 *   pos_def_len      | def A:[_]int, A.len                      | 3
 *   pos_local_ptr    | local [3]int, *a.ptr (sanctioned idiom) | 10
 *
 * The pos_local_ptr row pins that `.ptr`-on-array stays VALID (cgen
 * unchanged in this commit; the def-global `.ptr` cgen fix + its build+run
 * pin are task #11 / test 818, NOT here — so this control uses a LOCAL
 * array `.ptr`, which is correct in both stages today).
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/wait.h>

static int
runwait(const char *cmd)
{
	int rc = system(cmd);
	if (rc == -1) return -1;
	if (WIFEXITED(rc)) return WEXITSTATUS(rc);
	return -1;
}

struct row { const char *label; const char *src; int want; };

static const struct row rows[] = {
	{ "pos_local_len",
	  "package main;\n"
	  "export fn main() i32 = {\n"
	  "\tlet a: [3]int = [10, 20, 30];\n"
	  "\treturn a.len: i32;\n"
	  "};\n",
	  3 },

	{ "pos_def_len",
	  "package main;\n"
	  "def A: [_]int = [10, 20, 30];\n"
	  "export fn main() i32 = {\n"
	  "\treturn A.len: i32;\n"
	  "};\n",
	  3 },

	/* `.ptr`-on-array is the sanctioned ww spelling for &a[0] (task #13).
	 * LOCAL array `.ptr` is correct in BOTH stages today (cgen unchanged
	 * here); the def-global `.ptr` cgen fix is task #11 / test 818. */
	{ "pos_local_ptr",
	  "package main;\n"
	  "export fn main() i32 = {\n"
	  "\tlet a: [3]int = [10, 20, 30];\n"
	  "\tlet p: *int = a.ptr;\n"
	  "\treturn (*p): i32;\n"
	  "};\n",
	  10 },
};

/* `.cap` on a fixed array — both stages must FAIL the build (loud checker
 * diagnostic, not silent garbage / link-error). */
static const char *neg[] = {
	/* neg_local_cap */
	"package main;\n"
	"export fn main() i32 = {\n"
	"\tlet a: [3]int = [1, 2, 3];\n"
	"\treturn a.cap: i32;\n"
	"};\n",
	/* neg_def_cap */
	"package main;\n"
	"def A: [3]int = [1, 2, 3];\n"
	"export fn main() i32 = {\n"
	"\treturn A.cap: i32;\n"
	"};\n",
	/* neg_let_glob_cap */
	"package main;\n"
	"let G: [3]int = [1, 2, 3];\n"
	"export fn main() i32 = {\n"
	"\treturn G.cap: i32;\n"
	"};\n",
	/* neg_infer_cap — the #11 [_] infer path */
	"package main;\n"
	"def A: [_]int = [1, 2, 3];\n"
	"export fn main() i32 = {\n"
	"\treturn A.cap: i32;\n"
	"};\n",
};

static int
run_driver(const char *driver, const struct row *r, int i)
{
	char src[64], tmpdir[64], cmd[1024];
	snprintf(src, sizeof src, "/tmp/acr_%d_%d.ww", getpid(), i);
	snprintf(tmpdir, sizeof tmpdir, "/tmp/acr_%d_d_%d", getpid(), i);

	FILE *f = fopen(src, "wb");
	if (!f) return -1;
	fputs(r->src, f);
	fclose(f);

	mkdir(tmpdir, 0755);
	snprintf(cmd, sizeof cmd, "cd %s && %s build %s 2>/dev/null",
	    tmpdir, driver, src);
	if (runwait(cmd) != 0) {
		fprintf(stderr, "row[%s]: build via %s failed\n",
		    r->label, driver);
		unlink(src); rmdir(tmpdir);
		return -1;
	}

	const char *base = strrchr(src, '/');
	base = base ? base + 1 : src;
	char outbin[128];
	snprintf(outbin, sizeof outbin, "%s/%s", tmpdir, base);
	char *dot = strrchr(outbin, '.');
	if (dot && strcmp(dot, ".ww") == 0) *dot = '\0';
	int got = runwait(outbin);

	unlink(src); unlink(outbin); rmdir(tmpdir);
	return got;
}

/* build_should_fail — `.cap` on an array must error on `driver`; returns 0
 * when the build correctly FAILS, non-zero when it wrongly succeeded. */
static int
build_should_fail(const char *driver, const char *src, int i)
{
	char s[64], tmpdir[64], cmd[1024];
	snprintf(s, sizeof s, "/tmp/acrn_%d_%d.ww", getpid(), i);
	snprintf(tmpdir, sizeof tmpdir, "/tmp/acrn_%d_d_%d", getpid(), i);

	FILE *f = fopen(s, "wb");
	if (!f) return -1;
	fputs(src, f);
	fclose(f);

	mkdir(tmpdir, 0755);
	snprintf(cmd, sizeof cmd, "cd %s && %s build %s 2>/dev/null",
	    tmpdir, driver, s);
	int rc = runwait(cmd);
	unlink(s);
	/* clean any emitted binary */
	const char *base = strrchr(s, '/');
	base = base ? base + 1 : s;
	char outbin[128];
	snprintf(outbin, sizeof outbin, "%s/%s", tmpdir, base);
	char *dot = strrchr(outbin, '.');
	if (dot && strcmp(dot, ".ww") == 0) *dot = '\0';
	unlink(outbin);
	rmdir(tmpdir);
	return rc == 0 ? -1 : 0;	/* build must NOT succeed */
}

/* asm_byte_identical — w6c vs w6c_ww .s for the same source must match. */
static int
asm_byte_identical(const char *bin, const struct row *r, int i)
{
	char src[64], cs[64], ws[64], cmd[1024];
	snprintf(src, sizeof src, "/tmp/acr_asm_%d_%d.ww", getpid(), i);
	snprintf(cs,  sizeof cs,  "/tmp/acr_asm_%d_%d_c.s", getpid(), i);
	snprintf(ws,  sizeof ws,  "/tmp/acr_asm_%d_%d_w.s", getpid(), i);

	FILE *f = fopen(src, "wb");
	if (!f) return -1;
	fputs(r->src, f);
	fclose(f);

	snprintf(cmd, sizeof cmd, "%s/w6c -o %s %s 2>/dev/null", bin, cs, src);
	if (runwait(cmd) != 0) {
		fprintf(stderr, "row[%s]: w6c errored\n", r->label);
		unlink(src);
		return -1;
	}
	snprintf(cmd, sizeof cmd, "%s/w6c_ww -o %s %s 2>/dev/null",
	    bin, ws, src);
	if (runwait(cmd) != 0) {
		fprintf(stderr, "row[%s]: w6c_ww errored\n", r->label);
		unlink(src); unlink(cs);
		return -1;
	}

	FILE *fc = fopen(cs, "rb");
	FILE *fw = fopen(ws, "rb");
	int rc = 0;
	if (!fc || !fw) {
		rc = -1;
	} else {
		for (;;) {
			int a = fgetc(fc);
			int b = fgetc(fw);
			if (a != b) { rc = -1; break; }
			if (a == EOF) break;
		}
	}
	if (fc) fclose(fc);
	if (fw) fclose(fw);
	if (rc != 0)
		fprintf(stderr, "row[%s]: cstage vs wwstage asm differs\n",
		    r->label);
	unlink(src); unlink(cs); unlink(ws);
	return rc;
}

int
main(void)
{
	const char *bin = getenv("BIN");
	if (!bin) bin = "out/bin";
	char absbin[1024];
	if (bin[0] != '/') {
		char cwd[1024];
		if (getcwd(cwd, sizeof cwd) == NULL) return 1;
		snprintf(absbin, sizeof absbin, "%s/%s", cwd, bin);
		bin = absbin;
	}

	char cdrv[1024];
	snprintf(cdrv, sizeof cdrv, "%s/ww", bin);
	char wdrv[1024];
	snprintf(wdrv, sizeof wdrv, "%s/ww_ww", bin);

	struct { const char *name; const char *path; int gated_on_existence; }
	drivers[] = {
		{ "cstage",  cdrv, 0 },
		{ "wwstage", wdrv, 1 },
		{ NULL, NULL, 0 },
	};

	int n = (int)(sizeof rows / sizeof rows[0]);
	int nn = (int)(sizeof neg / sizeof neg[0]);
	int total = 0, fail = 0;

	for (int d = 0; drivers[d].name; d++) {
		if (drivers[d].gated_on_existence
		    && access(drivers[d].path, X_OK) != 0) {
			fprintf(stderr, "arr_cap_reject: skip %s (no %s)\n",
			    drivers[d].name, drivers[d].path);
			continue;
		}
		for (int i = 0; i < n; i++) {
			int got = run_driver(drivers[d].path, &rows[i], i);
			total++;
			if (got != rows[i].want) {
				fprintf(stderr,
				    "arr_cap_reject[%s][%s]: exit=%d want=%d\n",
				    drivers[d].name, rows[i].label,
				    got, rows[i].want);
				fail++;
			}
		}
		for (int i = 0; i < nn; i++) {
			total++;
			if (build_should_fail(drivers[d].path, neg[i],
			    100 + i) != 0) {
				fprintf(stderr,
				    "arr_cap_reject[%s][neg%d]: built ok, "
				    "expected a loud error\n",
				    drivers[d].name, i);
				fail++;
			}
		}
	}

	if (access(wdrv, X_OK) == 0) {
		for (int i = 0; i < n; i++) {
			total++;
			if (asm_byte_identical(bin, &rows[i], i) != 0)
				fail++;
		}
	}

	if (fail) {
		fprintf(stderr,
		    "arr_cap_reject: %d/%d fixtures failed\n", fail, total);
		return 1;
	}
	printf("arr_cap_reject: %d/%d ok\n", total, total);
	return 0;
}