// the user_task_region_* test cases. We only check for the
					// Go 1.21 traces because earlier traces used different
					// strings.
					switch ev.Kind() {
					case trace.EventRegionBegin, trace.EventRegionEnd:
						if _, ok := validRegions[ev.Region().Type]; !ok {
							t.Fatalf("converted event has unexpected region type:\n%s", ev)
						}
					case trace.EventTaskBegin, trace.EventTaskEnd:

				b.WriteString(`.\`)
			}
		case lastChar == ':':
			// If the path ends in a colon, keep the path relative to the current directory
			// on a drive and don't add a separator. Preserve leading slashes in the next
			// path element, which may make the path absolute.
			//
			// 	Join(`C:`, `f`) = `C:f`
			//	Join(`C:`, `\f`) = `C:\f`
		default:
			// In all other cases, add a separator between elements.
			b.WriteByte('\\')

	// N.B. Ignore the _Gscan bit. We don't model it in the tracer.
	var tgs traceGoStatus
	switch status &^ _Gscan {
	case _Grunnable:
		tgs = traceGoRunnable
	case _Grunning, _Gcopystack:
		tgs = traceGoRunning
	case _Gsyscall:
		tgs = traceGoSyscall
	case _Gwaiting, _Gpreempted:
		// There are a number of cases where a G might end up in
		// _Gwaiting but it's actually running in a non-preemptive

	switch outputFormat {
	case jsonOutput, yamlOutput, flagsOutput:
	default:
		return fmt.Errorf("unknown output format: %s", outputFormat)
	}
	return nil
}

// yamlToFormat converts the generated yaml config to the expected format
func yamlToFormat(yaml, outputFormat string) (string, error) {
	var output string
	switch outputFormat {
	case jsonOutput:
		j, err := yamlToPrettyJSON(yaml)

	// Note that we have an explicit return in each case, as that produces slightly better code (tested on Go 1.19).

	switch ev.Type {
	case EvGoCreate:
		g = ev.Args[0]
		init = gState{0, gDead}
		next = gState{1, gRunnable}
		return
	case EvGoWaiting, EvGoInSyscall:
		g = ev.G
		init = gState{1, gRunnable}
		next = gState{2, gWaiting}
		return
	case EvGoStart, EvGoStartLabel:
		g = ev.G

// platforms where osHasLowResClock is true, because the system clock
// isn't granular enough to get useful information out of a trace in
// many cases.
//
// This makes absolute values of timestamp diffs smaller, and so they are
// encoded in fewer bytes.
//
// The target resolution in all cases is 64 nanoseconds.
// This is based on the fact that fundamentally the execution tracer won't emit

		// case *MapType:
		// case *ChanType:

		// statements
		// case *EmptyStmt:
		// case *LabeledStmt:
		// case *BlockStmt:
		// case *ExprStmt:
		case *SendStmt:
			m = n.Chan
		// case *DeclStmt:
		case *AssignStmt:
			m = n.Lhs
		// case *BranchStmt:
		// case *CallStmt:
		// case *ReturnStmt:
		// case *IfStmt:
		// case *ForStmt:
		// case *SwitchStmt:
		// case *SelectStmt:

		// helper nodes

// If x and y are identical channels but for their direction
// and one of them is unrestricted, match returns the channel
// with the restricted direction.
// In all other cases, match returns nil.
func match(x, y Type) Type {
	// Common case: we don't have channels.
	if Identical(x, y) {
		return x
	}

	// We may have channels that differ in direction only.
	if x, _ := x.(*Chan); x != nil {

		completed: atomic.NewBool(false),
		d:         d,
		stop:      stop,
	}
}

func (c *fakeComponent) Run(stop <-chan struct{}) error {
	c.started.Store(true)
	select {
	case <-time.After(c.d):
	case <-c.stop: // ignore incoming stop; for test purposes we use our own stop
	}
	c.completed.Store(true)
	return nil

//
//	"field (T) f int"
//	"method (T) f(X) Y"
//	"method expr (T) f(X) Y"
func SelectionString(s *Selection, qf Qualifier) string {
	var k string
	switch s.kind {
	case FieldVal:
		k = "field "
	case MethodVal:
		k = "method "
	case MethodExpr:
		k = "method expr "
	default:
		panic("unreachable")
	}
	var buf bytes.Buffer
	buf.WriteString(k)
	buf.WriteByte('(')
	WriteType(&buf, s.Recv(), qf)