test: migrate 989_letshadow to @test value pin, retire C twin (fold-3)

#152 link-the-let-before-its-init miscompile (miscompiled IDENTICALLY on both stages, so byte-id 990-997 was blind; only a runtime value check catches it). Lifted the run fixture into test/lang/letshadow_test.ww (primitive @test value pin; byteid-eligible — symmetric, cs==ww). byteid floor 56->57. Closes the fold-3 #7 umbrella (last C test twin retired).

Makefile

@@ -510,7 +510,6 @@ TESTS	= $(BIN)/test_smoke $(BIN)/test_lex $(BIN)/test_parse $(BIN)/test_check \
 	  $(BIN)/test_strings_run \
 	  $(BIN)/test_hex_run $(BIN)/test_utf8_run $(BIN)/test_bytes_run \
 	  $(BIN)/test_path_run \
-	  $(BIN)/test_letshadow_run \
 	  $(BIN)/test_test_filter \
 	  $(BIN)/test_strconv_int_run \
 	  $(BIN)/test_stof_run $(BIN)/test_ftos_run \
@@ -2727,10 +2726,6 @@ $(BIN)/test_path_run: test/wcc/989_path_run.c $(BIN)/ww $(BIN)/w6c \
 		$(BIN)/w6a $(BIN)/w6l $(LIB)/libwwrt.a | $(BIN)
 	$(CC) $(CFLAGS) -o $@ $<
 
-$(BIN)/test_letshadow_run: test/wcc/989_letshadow_run.c $(BIN)/ww $(BIN)/w6c \
-		$(BIN)/w6a $(BIN)/w6l $(LIB)/libwwrt.a | $(BIN)
-	$(CC) $(CFLAGS) -o $@ $<
-
 $(BIN)/test_ascii_run: test/wcc/904_ascii_run.c $(BIN)/ww $(BIN)/w6c \
 		$(BIN)/w6a $(BIN)/w6l $(LIB)/libwwrt.a | $(BIN)
 	$(CC) $(CFLAGS) -o $@ $<
@@ -3269,7 +3264,7 @@ test-lang: all
 LANGBYTEID_DIR		= $(OUT)/langbyteid
 LANGBYTEID_FILES	= $(filter-out %_runonly_test.ww,$(wildcard test/lang/*_test.ww))
 LANGBYTEID_VERB		= test -c
-LANGBYTEID_EXPECTED_MIN	= 56
+LANGBYTEID_EXPECTED_MIN	= 57
 $(if $(LANGBYTEID_FILES),,$(error test-lang-byteid: empty corpus))
 test-lang-byteid: all
 	@set -e; \

test/lang/letshadow_test.ww

@@ -1,19 +1,13 @@
-// letshadow — #152 regression pin. A `let` binding must NOT be visible
+// letshadow_test — #152 regression pin, migrated from test/wcc/989_letshadow_run.c.
-// during its OWN initializer: `let x = f(x)` evaluates f(x) in the OUTER
-// scope (Hare: harec check.c clet runs cexpr before scope_define). Both
-// stages once linked the binding into the cgen localfind chain BEFORE
-// emitting the init, so the init read the fresh UNINIT shadow slot — a
-// silent miscompile identical on both stages (byte-id GREEN over it), so
-// this is a RUNTIME assertion. Signalled-then-exit(+10) pinpoints the row.
 //
-// Run with `out/bin/ww run test/wcc/989_letshadow.ww`; exit 0 = all pass.
+// A `let` binding must NOT be visible during its OWN initializer:
+// `let x = f(x)` evaluates f(x) in the OUTER scope (Hare: harec check.c clet
+// runs cexpr before scope_define). Both stages once linked the binding into
+// the cgen localfind chain BEFORE emitting the init, so the init read the
+// fresh UNINIT shadow slot — a silent miscompile IDENTICAL on both stages
+// (byte-id was GREEN over it), now fixed. PRIMITIVE-only (i32) asserts.
 
-package main;
+package letshadow_test;
-
-import os;
-
-let signalled: i32 = 0;
-fn fail() void = { os.exit(signalled + 10); };
 
 fn id(s: str) str = { return s; };
 
@@ -60,10 +54,18 @@ fn arrlitselfref() i32 = {
 	return r;
 };
 
-export fn main() i32 = {
+@test fn param_self_shadow() void = {
-	signalled = 1; if (paramshadow("hello") != 604) { fail(); };
+	assert(paramshadow("hello") == 604i32);
-	signalled = 2; if (letinletinit() != 6) { fail(); };
+};
-	signalled = 3; if (renamecontrol("hi") != 2) { fail(); };
+
-	signalled = 4; if (arrlitselfref() != 6) { fail(); };
+@test fn let_in_let_init() void = {
-	return 0;
+	assert(letinletinit() == 6i32);
+};
+
+@test fn rename_control() void = {
+	assert(renamecontrol("hi") == 2i32);
+};
+
+@test fn arrlit_self_ref() void = {
+	assert(arrlitselfref() == 6i32);
 };

test/wcc/989_letshadow_run.c

@@ -1,50 +0,0 @@
-/*
- * 989_letshadow_run — #152 regression pin. Compile + run the letshadow
- * fixture under the C-side `ww run` driver (cstage w6c) and assert exit 0.
- *
- * The bug (link-the-let-before-its-init) miscompiled IDENTICALLY on both
- * stages, so byte-id 990-997 is blind to it; only a runtime value check
- * catches the regression. Same thin-wrapper shape as 989_path_run.
- */
-#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 = "test/wcc/989_letshadow.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, "letshadow_run FAIL: %s exited %d "
-		    "(row %d miscompiled — #152)\n", src, rc, rc - 10);
-		return 1;
-	}
-	printf("letshadow_run: %s ok\n", src);
-	return 0;
-}