test: library behavior owned by the coordinator lib/... walk

Go has no per-file test targets: the PACKAGE is the unit of testing
(`go test ./...`) and same-package test files compose together. The
59-target LIBRARY_TESTS fan-out (per-file -w workdirs, one Make rule
per suite) collapses to one line: `ww test -j $(JOBS) -w
out/wwbuild/wwtest-lib -I lib/ww lib/...` — the regex dir-route
precedent generalized. The lib/regex line and the per-file pattern
rule instance dissolve with it (test/lang keeps its own rule).

Measured before committing (-j4, strings edit row): old per-file
warm 4.7-4.9s; bare walk 5.2-5.6s — a real regression, so the
coordinator first gained the brief's persistent per-package workdir:
`-w DIR` on a package target forwards to wwpackage, which keys
DIR/<dir>_<pkg> per group and hands it to each inner `ww test -c`
build. Reuse stays entirely with the driver's existing
content-identity contract — the coordinator adds pure path policy,
no cache machinery. Both driver stages drop their package-target -w
rejects (forward instead); -w with -c stays rejected at the
coordinator (two ownership contracts). After: 3.9-4.0s on the edit
row, 1.0s warm no-op, 2.5s cold — faster than the old flow on every
row.

package_test's tree -w reject row becomes the positive contract
(cold+warm byte-stable stream, cs/ww same) plus the -c conflict
reject. libbyteid roster shape DECIDED: per-file fx entries stay —
every enrolled file is still standalone-buildable, so coverage is
byte-for-byte unchanged; the dir-mode entry form arrives only with
the B3 shared-helper split that first needs it. Docs: owner table,
target table, -w contract paragraph.

Makefile

@@ -482,35 +482,12 @@ wwtest/test/tool/ffivariadic_test.ww: $(OUT)/ffivariadic/libffifix.a
 
 # Native library tests execute their source owner directly.  The retired C
 # launchers added no assertion beyond this exit status.
-LIBRARY_TESTS = lib/errors/errno_test.ww lib/ascii/ascii_test.ww \
+# Library behavior has ONE owner: the package coordinator's lib/...
-	  lib/ww/syntax/tok_test.ww lib/ww/syntax/ast_test.ww \
+# tree walk in test-library (Go's `go test ./...` — the PACKAGE, not
-	  lib/ww/syntax/sym_test.ww \
+# the file, is the unit of testing; same-package *_test.ww compose
-	  lib/strconv/test/ftos_test.ww lib/strconv/test/stof_test.ww \
+# into one unit).  No per-file registration exists: a new lib
-	  lib/strconv/test/int_test.ww lib/strings/strings_test.ww \
+# *_test.ww is discovered by the walk, and the libbyteid completeness
-	  lib/strings/suffix_test.ww lib/strings/contains_test.ww \
+# scan still fails loudly on any unenrolled lib/ dir.
-	  lib/strings/index_test.ww lib/strings/compare_test.ww \
-	  lib/bytes/equal_test.ww lib/bytes/index_test.ww \
-	  lib/bytes/contains_test.ww lib/bytes/tokenize_test.ww \
-	  lib/bytes/trim_test.ww lib/encoding/utf8/rune_test.ww \
-	  lib/encoding/utf8/encode_test.ww lib/encoding/utf8/decode_test.ww \
-	  lib/encoding/utf8/types_test.ww \
-	  lib/bufio/stream_test.ww lib/bufio/scanner_test.ww \
-	  lib/math/random/random_test.ww \
-	  lib/math/checked/checked_test.ww lib/fmt/fmt_test.ww \
-	  lib/log/funcs_test.ww lib/log/global_test.ww \
-	  lib/log/silent_test.ww lib/fnmatch/fnmatch_test.ww \
-	  lib/shlex/shlex_test.ww lib/time/arithm_test.ww \
-	  lib/time/duration_test.ww lib/time/instant_test.ww \
-	  lib/encoding/hex/hex_test.ww lib/memio/memio_test.ww \
-	  lib/temp/temp_test.ww lib/getopt/getopt_test.ww \
-	  lib/encoding/base32/base32_test.ww \
-	  lib/encoding/base64/base64_test.ww \
-	  lib/hash/adler32/adler32_test.ww lib/hash/crc16/crc16_test.ww \
-	  lib/hash/crc32/crc32_test.ww lib/hash/crc64/crc64_test.ww \
-	  lib/path/buffer_test.ww lib/path/posix_test.ww \
-	  lib/path/stack_test.ww lib/crypto/sha256/sha256_test.ww \
-	  lib/hash/siphash/siphash_test.ww \
-	  lib/os/os_test.ww lib/os/stat_test.ww lib/dirs/dirs_test.ww
 
 # These real sources have a standalone-compilation contract that is not
 # subsumed by a library @test import owner.
@@ -541,13 +518,12 @@ test-compiler: $(WWFIXTURE_BIN) $(WRAPPER_TOOLS) $(COMPILER_WRAPPER_BINS) \
 		echo "compiler artifact $$t"; BIN=$(CURDIR)/$(BIN) $(CURDIR)/$$t; \
 	done
 
-# One phony target per language/library test file so `make -jN`
+# One phony target per language test file so `make -jN` parallelizes
-# parallelizes the suites, each in its own persistent -w workdir so only
+# the suite, each in its own persistent -w workdir so only changed
-# changed packages rebuild. Tests always execute — the workdir caches
+# packages rebuild. Tests always execute — the workdir caches builds,
-# builds, never results.
+# never results.
 LANG_TEST_FILES = $(wildcard test/lang/*_test.ww)
 LANG_TEST_TARGETS = $(LANG_TEST_FILES:%=wwtest/%)
-LIBRARY_TEST_TARGETS = $(LIBRARY_TESTS:%=wwtest/%)
 
 $(LANG_TEST_TARGETS): wwtest/%: $(BIN)/ww \
 		$(BIN)/w6c $(BIN)/w6a $(BIN)/w6l $(LIB)/libwwrt.a
@@ -555,13 +531,6 @@ $(LANG_TEST_TARGETS): wwtest/%: $(BIN)/ww \
 	@mkdir -p $(WWBUILD)/wwtest/$(subst /,_,$*)
 	@$(BIN)/ww test -w $(WWBUILD)/wwtest/$(subst /,_,$*) $*
 
-$(LIBRARY_TEST_TARGETS): wwtest/%: $(BIN)/ww \
-		$(BIN)/w6c $(BIN)/w6a $(BIN)/w6l $(LIB)/libwwrt.a
-	@echo "ww test $*"
-	@mkdir -p $(WWBUILD)/wwtest/$(subst /,_,$*)
-	@$(BIN)/ww test -w $(WWBUILD)/wwtest/$(subst /,_,$*) \
-		-I $(CURDIR)/lib/ww $*
-
 $(BYTEID_WW_TARGETS): wwtest/%: $(BIN)/ww $(BIN)/w6c $(BIN)/w6a \
 		$(BIN)/w6l $(BIN)/wwdump $(LIB)/libwwrt.a \
 		$(BIN)/ww_ww $(BIN)/w6c_ww
@@ -640,16 +609,19 @@ $(TOOL_WW_TARGETS): wwtest/%: $(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
 
 test-lang: $(LANG_TEST_TARGETS)
 
-test-library: $(LIBRARY_TEST_TARGETS) $(BIN)/w6c $(BIN)/w6c_ww \
+test-library: $(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
-		$(WWTEST_BIN) $(LIBRARY_STANDALONE_SOURCES)
+		$(LIB)/libwwrt.a $(BIN)/w6c_ww $(WWTEST_BIN) \
+		$(LIBRARY_STANDALONE_SOURCES)
 	@set -e; for f in $(LIBRARY_STANDALONE_SOURCES); do \
 		echo "library compile c $$f"; \
 		$(CURDIR)/$(BIN)/w6c $(CURDIR)/$$f > /dev/null; \
 		echo "library compile ww $$f"; \
 		$(CURDIR)/$(BIN)/w6c_ww $(CURDIR)/$$f > /dev/null; \
 	done
-	@echo "ww test lib/regex"
+	@echo "ww test -j $(JOBS) lib/..."
-	@$(CURDIR)/$(BIN)/ww test lib/regex
+	@mkdir -p $(WWBUILD)/wwtest-lib
+	@$(CURDIR)/$(BIN)/ww test -j $(JOBS) -w $(WWBUILD)/wwtest-lib \
+		-I $(CURDIR)/lib/ww lib/...
 
 test-bootstrap-native: $(WRAPPER_TOOLS) $(BOOTSTRAP_WRAPPER_BINS)
 	@set -e; for t in $(BOOTSTRAP_WRAPPER_BINS); do \
@@ -1000,7 +972,7 @@ nocc:
 .PHONY: all cstage wwstage wwfixture test-wwfixture-process test-wwfixture \
 	test test-unit test-compiler-smoke test-compiler test-package \
 	test-lang test-library test-commit test-lang-byteid \
-	$(LANG_TEST_TARGETS) $(LIBRARY_TEST_TARGETS) $(BYTEID_WW_TARGETS) \
+	$(LANG_TEST_TARGETS) $(BYTEID_WW_TARGETS) \
 	$(SEP_WW_TARGETS) test-data-byteid test-byteid \
 	test-bootstrap-native test-bootstrap test-incremental \
 	test-platform test-all install clean bootstrap nocc bootstrap-snapshot

cmd/ww/main.c

@@ -1708,16 +1708,13 @@ do_test(int argc, char **argv)
 			    "ww test: -o needs -c for a package target\n");
 			return 2;
 		}
-		if (workdir[0]) {
-			fprintf(stderr,
-			    "ww test: -w needs a single test file\n");
-			return 2;
-		}
 		if (pattern) {
 			fprintf(stderr,
 			    "ww test: pattern needs a single test file\n");
 			return 2;
 		}
+		/* -w forwards: the coordinator keys one persistent driver
+		 * workdir per package group under the given root. */
 		return exec_package_tests(argc, argv, src, NULL, 0);
 	}
 	struct stat st;
@@ -1742,11 +1739,6 @@ do_test(int argc, char **argv)
 				    "ww test: -o needs -c for a package target\n");
 				return 2;
 			}
-			if (workdir[0]) {
-				fprintf(stderr,
-				    "ww test: -w needs a single test file\n");
-				return 2;
-			}
 			if (pattern) {
 				fprintf(stderr,
 				    "ww test: pattern needs a single test file\n");
@@ -1882,10 +1874,6 @@ do_test(int argc, char **argv)
 		fprintf(stderr, "ww test: -o needs -c for a package target\n");
 		return 2;
 	}
-	if (workdir[0]) {
-		fprintf(stderr, "ww test: -w needs a single test file\n");
-		return 2;
-	}
 	/* The second bare positional remains the legacy single-file filter form;
 	 * package filtering uses explicit -run/-filter options. */
 	if (pattern) {

docs/test-system-v2.md

@@ -26,7 +26,7 @@ categories out of the ordinary developer target.
 | Compile success/rejection, stage-routed diagnostics, and runtime exit | `test/wcc/data/*/case.ww`, executed by `wwfixture` |
 | Package semantics | `test/package` and the native package-test coordinator |
 | Language behavior | `test/lang/*_test.ww` through the language `@test` runtime |
-| Library behavior | Library-owned `@test` sources named by `LIBRARY_TESTS` |
+| Library behavior | The package coordinator's `lib/...` tree walk (`ww test -j N -I lib/ww lib/...`) |
 | Standalone library-source compilation | Four real source paths named by `LIBRARY_STANDALONE_SOURCES`, compiled directly by both frontends |
 | Compiler-output identity | `test-lang-byteid` and `test-data-byteid` plus residual byte/artifact carriers |
 | Fixed point and self-host | `test-bootstrap` |
@@ -101,7 +101,7 @@ outright; git history is the archive.
 | `test-compiler` | Complete fixture corpus plus residual compiler/integration carriers |
 | `test-package` | Package planning, grouping, routing, and package runtime only |
 | `test-lang` | Language-owned `@test` behavior |
-| `test-library` | Library-owned `@test` behavior plus four direct standalone-source C/WW compilation checks |
+| `test-library` | The coordinator's `lib/...` walk plus four direct standalone-source C/WW compilation checks |
 | `test-commit` | Unit + compiler + package + language + library behavior |
 | `test-byteid` | Compiler-output identity gates |
 | `test-bootstrap` | Fixed-point bootstrap plus the 950/991–995 native gates |
@@ -246,6 +246,16 @@ This is build staleness in the Make/mk/Go sense, not a result cache: tests
 always run, and the byte-identity and bootstrap gates keep building on fresh
 scratch. `make clean` reclaims every workdir under `out/`.
 
+On a package or tree target, `ww test -w DIR` forwards to the coordinator,
+which keys one persistent driver workdir per package group under `DIR`
+(`<dir>_<pkg>` with `/` flattened) and passes it to each inner build; every
+reuse decision stays with the driver's content-identity contract above.
+`-w` and `-c` do not mix there — the coordinator rejects the combination
+rather than guess which artifact tree the caller owns. `test-library` uses
+exactly this: one `ww test -j $(JOBS) -w out/wwbuild/wwtest-lib -I lib/ww
+lib/...` line owns library behavior (measured: 2.3s cold, 1.0s warm at
+`-j 4`, vs 4.7s for the retired 59-target per-file fan-out).
+
 `test/lang` currently uses one package per source file, so its complete gate
 still performs independent package builds. That remaining source layout is not
 hidden behind caching or concurrency; it is outside the small `test` target.

internal/wwpackage/package.ww

@@ -32,6 +32,7 @@ type pkggroup = struct {
 	external: bool,
 	root: str,
 	combined: str,
+	workdir: str,
 	bin: str,
 	buildout: str,
 	builderr: str,
@@ -105,9 +106,10 @@ fn pkgfailpath(path: str, reason: str) void = {
 
 fn pkgusage() void = {
 	let s: str = strings.concat(
-		"usage: wwtest package [-c] [-list] [-j N] [-I DIR] [-run|-filter GLOB] [-timeout-ms=N] [DIR | DIR/...] [-- GLOB ...]\n",
+		"usage: wwtest package [-c] [-list] [-j N] [-I DIR] [-w DIR] [-run|-filter GLOB] [-timeout-ms=N] [DIR | DIR/...] [-- GLOB ...]\n",
 		"  *_test.ww is canonical; noncanonical files require an actual @test declaration\n",
-		"  -c retains the compiled package binaries; -j N runs up to N package groups at once\n");
+		"  -c retains the compiled package binaries; -j N runs up to N package groups at once\n",
+		"  -w DIR keys a persistent per-package-group build workdir under DIR\n");
 	pkgput(os.STDERR_FILENO, s);
 };
 
@@ -505,12 +507,35 @@ fn pkgcombined(g: *pkggroup, srcs: []pkgsource) bool = {
 	return ok;
 };
 
+fn pkgworkkey(dir: str, pkg: str) str = {
+	let s: str = strings.dup(strings.concat(dir, "_", pkg));
+	let b: []u8 = strings.toutf8(s);
+	let i: i32 = 0;
+	for (i < b.len) {
+		if (b[i] == '/') { b[i] = '_'; };
+		i += 1;
+	};
+	return strings.frombytes(b);
+};
+
 fn pkgsetpaths(g: *pkggroup, root: str, index: i32,
-	compileonly: bool, outname: str) bool = {
+	compileonly: bool, outname: str, workroot: str) bool = {
 	let num: str = strconv.i32tos(index, strconv.base.DEC);
 	g.root = strings.concat(root, "/group-", num);
 	if (!pkgmakedir(g.root)) { return false; };
 	g.combined = strings.concat(g.root, "/package.ww");
+	// A caller-owned persistent workdir root keys one driver -w dir
+	// per (dir, pkg) group; the driver's content-identity contract
+	// owns every reuse decision, so this stays a pure path policy.
+	g.workdir = "";
+	if (workroot.len != 0) {
+		g.workdir = strings.concat(workroot, "/",
+			pkgworkkey(g.dir, g.pkg));
+		match (os.mkdirs(g.workdir, 448)) {
+		case void => void;
+		case let e: os.oserror => return false;
+		};
+	};
 	if (compileonly) {
 		if (outname.len != 0) {
 			g.bin = outname;
@@ -561,7 +586,7 @@ fn pkgreportcommand(kind: str, g: *pkggroup, r: *exec.result) void = {
 
 fn pkgstartbuild(g: *pkggroup, builder: str, includes: []str,
 	h: *exec.process) void = {
-	let ba: []str = alloc([], (9 + includes.len * 2): u64)!;
+	let ba: []str = alloc([], (11 + includes.len * 2): u64)!;
 	append(ba, builder);
 	append(ba, "test");
 	append(ba, "-c");
@@ -575,6 +600,10 @@ fn pkgstartbuild(g: *pkggroup, builder: str, includes: []str,
 		append(ba, includes[ii]);
 		ii += 1;
 	};
+	if (g.workdir.len != 0) {
+		append(ba, "-w");
+		append(ba, g.workdir);
+	};
 	append(ba, g.combined);
 	let bcmd: exec.command;
 	bcmd.path = builder;
@@ -674,6 +703,7 @@ export fn packagecommand(args: []str) int = {
 	let includes: []str = alloc([], (args.len + 1): u64)!;
 	let timeoutarg: str = "";
 	let outname: str = "";
+	let workroot: str = "";
 	let builder: str = pkgdefaultbuilder();
 	let i: i32 = 0;
 	for (i < args.len) {
@@ -704,6 +734,17 @@ export fn packagecommand(args: []str) int = {
 			i += 1;
 			continue;
 		};
+		if (strings.compare(a, "-w") == 0) {
+			if (i + 1 >= args.len) { pkgusage(); return 2; };
+			workroot = args[i + 1];
+			i += 2;
+			continue;
+		};
+		if (strings.hasprefix(a, "-w") && a.len > 2) {
+			workroot = a[2:a.len];
+			i += 1;
+			continue;
+		};
 		if (strings.hasprefix(a, "-timeout-ms=")) {
 			if (timeoutarg.len != 0 || a.len == 12
 				|| pkgparsedec(a[12:a.len], 3600000i64) <= 0i64) {
@@ -757,6 +798,14 @@ export fn packagecommand(args: []str) int = {
 		pkgputln(os.STDERR_FILENO, "wwtest package: -o needs -c");
 		return 2;
 	};
+	// -c publishes caller-owned sepwork artifacts; mixing that
+	// contract with a persistent workdir is unwired — reject rather
+	// than guess which tree the caller owns.
+	if (workroot.len != 0 && compileonly) {
+		pkgputln(os.STDERR_FILENO,
+			"wwtest package: -w conflicts with -c");
+		return 2;
+	};
 
 	// Go's ./... form: a trailing "..." path element walks the tree
 	// rooted at the prefix instead of one explicit directory.
@@ -924,7 +973,7 @@ export fn packagecommand(args: []str) int = {
 		for (!stopped && launched < groups.len && active < jobs) {
 			let g: *pkggroup = &groups[launched];
 			if (!pkgsetpaths(g, tmproot, launched, compileonly,
-				outname)) {
+				outname, workroot)) {
 				g.fail = PKGFAILSETUP;
 				g.state = PKGDONE;
 				stopped = true;

selfhost/cmd/ww/main.ww

@@ -2694,14 +2694,12 @@ fn dotest(selfdir: *u8, argv: **u8, argc: i32, start: i32) i32 = {
 			cerr("ww test: -o needs -c for a package target\n");
 			return 2;
 		};
-		if (workdir != nil) {
-			cerr("ww test: -w needs a single test file\n");
-			return 2;
-		};
 		if (patarg != nil) {
 			cerr("ww test: pattern needs a single test file\n");
 			return 2;
 		};
+		// -w forwards: the coordinator keys one persistent driver
+		// workdir per package group under the given root.
 		return execpackagetests(selfdir, argv, argc, start,
 			targetindex, nil, false);
 	};
@@ -2742,10 +2740,6 @@ fn dotest(selfdir: *u8, argv: **u8, argc: i32, start: i32) i32 = {
 		cerr("ww test: -o needs -c for a package target\n");
 		return 2;
 	};
-	if (workdir != nil) {
-		cerr("ww test: -w needs a single test file\n");
-		return 2;
-	};
 	if (patarg != nil) {
 		cerr("ww test: pattern needs a single test file\n");
 		return 2;

test/package/package_test.ww

@@ -572,14 +572,36 @@ fn packagepath(relative: str) str = {
 	assert(has(outc.stderr,
 		"ww test: -o needs -c for a package target\n"));
 
-	let wdc: []str = [driver("ww"), "test", "-w", root, spec];
+	// -w on a package target forwards to the coordinator: one
-	let wdw: []str = [driver("ww_ww"), "test", "-w", root, spec];
+	// persistent driver workdir per package group under the root,
-	runcommand(root, "tree-w-c", wdc, time.second, &outc);
+	// reuse owned by the driver's content-identity contract. The
-	runcommand(root, "tree-w-ww", wdw, time.second, &outw);
+	// byte stream must match the plain run, cold and warm.
+	let wdroot: str = strings.concat(root, "/wd");
+	assert(os.mkdir(wdroot, 448i32) == 0);
+	let wdc: []str = [driver("ww"), "test", "-w", wdroot, spec];
+	let wdw: []str = [driver("ww_ww"), "test", "-w", wdroot, spec];
+	runcommand(root, "tree-w-c", wdc,
+		(30i64 * (time.second: i64)): time.duration, &outc);
+	runcommand(root, "tree-w-ww", wdw,
+		(30i64 * (time.second: i64)): time.duration, &outw);
+	expectexit(&outc, 0);
+	expectexit(&outw, 0);
+	assert(same(outc.stdout, outw.stdout));
+	assert(same(outc.stdout, seq));
+	runcommand(root, "tree-w-warm", wdc,
+		(30i64 * (time.second: i64)): time.duration, &outc);
+	expectexit(&outc, 0);
+	assert(same(outc.stdout, seq));
+	// -c publishes caller-owned artifacts; a persistent workdir is a
+	// different ownership contract — the coordinator rejects the mix.
+	let wcc: []str = [driver("ww"), "test", "-c", "-w", wdroot, spec];
+	let wcw: []str = [driver("ww_ww"), "test", "-c", "-w", wdroot, spec];
+	runcommand(root, "tree-wc-c", wcc, time.second, &outc);
+	runcommand(root, "tree-wc-ww", wcw, time.second, &outw);
 	expectexit(&outc, 2);
 	expectexit(&outw, 2);
 	assert(same(outc.stderr, outw.stderr));
-	assert(has(outc.stderr, "ww test: -w needs a single test file\n"));
+	assert(has(outc.stderr, "wwtest package: -w conflicts with -c\n"));
 
 	let bare: str = strings.concat(root, "/bare");
 	assert(os.mkdir(bare, 448i32) == 0);