{14, "SIGALRM", "alarm clock"},
	{15, "SIGTERM", "terminated"},
	{16, "SIGUSR1", "user defined signal 1"},
	{17, "SIGUSR2", "user defined signal 2"},
	{18, "SIGCHLD", "child exited"},
	{19, "SIGPWR", "power failure"},
	{20, "SIGWINCH", "window changed"},
	{21, "SIGURG", "urgent I/O condition"},
	{22, "SIGIO", "I/O possible"},
	{23, "SIGSTOP", "stopped (signal)"},
	{24, "SIGTSTP", "stopped"},
	{25, "SIGCONT", "continued"},

	{14, "SIGALRM", "alarm clock"},
	{15, "SIGTERM", "terminated"},
	{16, "SIGUSR1", "user defined signal 1"},
	{17, "SIGUSR2", "user defined signal 2"},
	{18, "SIGCHLD", "child exited"},
	{19, "SIGPWR", "power failure"},
	{20, "SIGWINCH", "window changed"},
	{21, "SIGURG", "urgent I/O condition"},
	{22, "SIGIO", "I/O possible"},
	{23, "SIGSTOP", "stopped (signal)"},
	{24, "SIGTSTP", "stopped"},
	{25, "SIGCONT", "continued"},

func (u *URL) IsAbs() bool {
	return u.Scheme != ""
}

// Parse parses a [URL] in the context of the receiver. The provided URL
// may be relative or absolute. Parse returns nil, err on parse
// failure, otherwise its return value is the same as [URL.ResolveReference].
func (u *URL) Parse(ref string) (*URL, error) {
	refURL, err := Parse(ref)
	if err != nil {
		return nil, err
	}

			t.Skipf("creating and observing contention on runtime-internal semaphores requires GOMAXPROCS >= %d", workers)
		}

		var sem uint32 = 1
		var tries atomic.Int32
		tries.Store(10_000_000) // prefer controlled failure to timeout
		var sawContention atomic.Int32
		var need int32 = 1
		fn := func() bool {
			if sawContention.Load() >= need {
				return false
			}
			if tries.Add(-1) < 0 {
				return false

	// These are all larger than any real SP.

	// Goroutine preemption request.
	// 0xfffffade in hex.
	stackPreempt = uintptrMask & -1314

	// Thread is forking. Causes a split stack check failure.
	// 0xfffffb2e in hex.
	stackFork = uintptrMask & -1234

	// Force a stack movement. Used for debugging.
	// 0xfffffeed in hex.
	stackForceMove = uintptrMask & -275

		}
		var dialed bool
		select {
		case <-dialedc:
			dialed = true
		default:
		}

		if !tt.ok && dialed {
			t.Errorf("For key %q, value %q, transport dialed. Expected local failure. Response was: (%v, %v)\nServer replied with: %s", tt.key, tt.val, res, err, body)
		} else if (err == nil) != tt.ok {
			t.Errorf("For key %q, value %q; got err = %v; want ok=%v", tt.key, tt.val, err, tt.ok)
		}
	}

	{26, "SIGVTALRM", "virtual timer expired"},
	{27, "SIGPROF", "profiling timer expired"},
	{28, "SIGWINCH", "window changed"},
	{29, "SIGIO", "I/O possible"},
	{30, "SIGPWR", "power failure"},
	{31, "SIGSYS", "bad system call"},

	{26, "SIGVTALRM", "virtual timer expired"},
	{27, "SIGPROF", "profiling timer expired"},
	{28, "SIGWINCH", "window changed"},
	{29, "SIGIO", "I/O possible"},
	{30, "SIGPWR", "power failure"},
	{31, "SIGSYS", "bad system call"},

		ctx := trace.StartGoroutine(ctx)
		go func(p string, r *result) {
			r.QueryResult, r.err = queryModule(ctx, p)
			wg.Done()
		}(p, &results[i])
	}
	wg.Wait()

	// Classify the results. In case of failure, identify the error that the user
	// is most likely to find helpful: the most useful class of error at the
	// longest matching path.
	var (
		noPackage      *PackageNotInModuleError

	if n != len(buf) || err != nil || string(buf) != "O:hi\n" {
		t.Fatalf("ReadFull = %d, %v, %q", n, err, buf[:n])
	}
	go cancel()

	if err := c.Wait(); err == nil {
		t.Fatal("expected Wait failure")
	}
}

func TestContextCancel(t *testing.T) {
	if runtime.GOOS == "netbsd" && runtime.GOARCH == "arm64" {
		maySkipHelperCommand("cat")
		testenv.SkipFlaky(t, 42061)
	}