From 79c758c046268a4a56b2ab6ee50c34b0037c3552 Mon Sep 17 00:00:00 2001
From: Hojun-Cho <ghwns6743@gmail.com>
Date: Thu, 14 May 2026 02:51:49 +0900
Subject: [PATCH] test: wire lib/bufio/bufiotest.ww into make test (closes #23)

Closes the coverage gap that hid task #22's pointer-rooted N_DOT bug:
test/wcc/900_stdlib.c claimed "Coverage lives at lib/bufio/bufiotest.ww"
but no test/wcc/*.c ran bufiotest. New 998_bufio_run runs it and
propagates exit; matches 910_at_test pattern.
---
 Makefile                 |  7 ++++-
 test/wcc/998_bufio_run.c | 58 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 64 insertions(+), 1 deletion(-)
 create mode 100644 test/wcc/998_bufio_run.c

diff --git a/Makefile b/Makefile
index b4f6a4e6..027ed368 100644
--- a/Makefile
+++ b/Makefile
@@ -222,7 +222,8 @@ TESTS	= $(BIN)/test_smoke $(BIN)/test_lex $(BIN)/test_parse $(BIN)/test_check \
 	  $(BIN)/test_field_signed $(BIN)/test_frame_argcount \
 	  $(BIN)/test_selfhost $(BIN)/test_w6a_ww $(BIN)/test_w6l_ww \
 	  $(BIN)/test_w6c_ww $(BIN)/test_ww_ww $(BIN)/test_self_rebuild \
-	  $(BIN)/test_dyn_ww $(BIN)/test_selfcheck $(BIN)/test_at_test_ww
+	  $(BIN)/test_dyn_ww $(BIN)/test_selfcheck $(BIN)/test_at_test_ww \
+	  $(BIN)/test_bufio_run
 
 $(BIN)/test_smoke: test/wcc/000_smoke.c $(LIB)/libwcc.a | $(BIN)
 	$(CC) $(CFLAGS) $(INCS) -o $@ $< -L$(LIB) -lwcc
@@ -356,6 +357,10 @@ $(BIN)/test_at_test_ww: test/wcc/997_at_test_ww.c $(BIN)/ww_ww $(BIN)/w6c_ww \
 		$(BIN)/w6a_ww $(BIN)/w6l_ww $(LIB)/libwwrt.a | $(BIN)
 	$(CC) $(CFLAGS) -o $@ $<
 
+$(BIN)/test_bufio_run: test/wcc/998_bufio_run.c $(BIN)/ww $(BIN)/w6c \
+		$(BIN)/w6a $(BIN)/w6l $(LIB)/libwwrt.a | $(BIN)
+	$(CC) $(CFLAGS) -o $@ $<
+
 test: all $(TESTS)
 	@WW=$(BIN)/ww BIN=$(BIN) sh test/run
 
diff --git a/test/wcc/998_bufio_run.c b/test/wcc/998_bufio_run.c
new file mode 100644
index 00000000..8ef875fd
--- /dev/null
+++ b/test/wcc/998_bufio_run.c
@@ -0,0 +1,58 @@
+/*
+ * 998_bufio_run — execute the lib/bufio @test fixture under the
+ * C-side `ww run` driver and assert exit 0.
+ *
+ * Why this exists: lib/bufio/bufio.ww was lifted out of the
+ * w6c-compile sweep in 900_stdlib because its cross-module type
+ * refs only resolve once the driver concatenates `use`d modules.
+ * That note ("Coverage lives at lib/bufio/bufiotest.ww") was true
+ * in intent but not in fact — nothing actually ran bufiotest.ww
+ * under `make test`. Bug #22 (pointer-rooted chained N_DOT) hid
+ * in that gap. This harness closes it.
+ *
+ * bufiotest.ww carries its own `export fn main()` that drives the
+ * @test fns and signals which case failed via the exit code, so
+ * this file is just a thin wrapper — no @test scanning, no
+ * synthetic main generation.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.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;
+}
+
+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 cwd[1024];
+	if (getcwd(cwd, sizeof cwd) == NULL) return 1;
+
+	const char *src = "lib/bufio/bufiotest.ww";
+	char path[1024], cmd[2048];
+	snprintf(path, sizeof path, "%s/%s", cwd, src);
+	snprintf(cmd, sizeof cmd, "%s/ww run %s", bin, path);
+	int rc = runwait(cmd);
+	if (rc != 0) {
+		fprintf(stderr, "bufio_run FAIL: %s exited %d\n", src, rc);
+		return 1;
+	}
+	printf("bufio_run: %s ok\n", src);
+	return 0;
+}