fix(output): status report ignored when assumeTTY or unsafe is true

Assuming that tty is of type File makes termStatusReport fail.

output.go

@@ -178,9 +178,12 @@ func (o *Output) HasDarkBackground() bool {
 	return l < 0.5
 }
 
-// TTY returns the terminal's file descriptor. This may be nil if the output is
+// TTY returns the underlying terminal output. This may be nil if the output is
 // not a terminal.
-func (o Output) TTY() File {
+func (o Output) TTY() io.Writer {
+	if o.assumeTTY || o.unsafe {
+		return o.tty
+	}
 	if f, ok := o.tty.(File); ok {
 		return f
 	}

termenv.go

@@ -31,11 +31,11 @@ func (o *Output) isTTY() bool {
 	if len(o.environ.Getenv("CI")) > 0 {
 		return false
 	}
-	if o.TTY() == nil {
-		return false
+	if f, ok := o.TTY().(File); ok {
+		return isatty.IsTerminal(f.Fd())
 	}
 
-	return isatty.IsTerminal(o.TTY().Fd())
+	return false
 }
 
 // ColorProfile returns the supported color profile:

termenv_unix.go

@@ -109,8 +109,8 @@ func (o Output) backgroundColor() Color {
 	return ANSIColor(0)
 }
 
-func (o *Output) waitForData(timeout time.Duration) error {
-	fd := o.TTY().Fd()
+func (o *Output) waitForData(tty File, timeout time.Duration) error {
+	fd := tty.Fd()
 	tv := unix.NsecToTimeval(int64(timeout))
 	var readfds unix.FdSet
 	readfds.Set(int(fd))
@@ -133,15 +133,15 @@ func (o *Output) waitForData(timeout time.Duration) error {
 	return nil
 }
 
-func (o *Output) readNextByte() (byte, error) {
-	if !o.unsafe {
-		if err := o.waitForData(OSCTimeout); err != nil {
+func (o *Output) readNextByte(tty io.ReadWriter) (byte, error) {
+	if f, ok := tty.(File); ok && !o.unsafe {
+		if err := o.waitForData(f, OSCTimeout); err != nil {
 			return 0, err
 		}
 	}
 
 	var b [1]byte
-	n, err := o.TTY().Read(b[:])
+	n, err := tty.Read(b[:])
 	if err != nil {
 		return 0, err
 	}
@@ -156,15 +156,15 @@ func (o *Output) readNextByte() (byte, error) {
 // readNextResponse reads either an OSC response or a cursor position response:
 //   - OSC response: "\x1b]11;rgb:1111/1111/1111\x1b\\"
 //   - cursor position response: "\x1b[42;1R"
-func (o *Output) readNextResponse() (response string, isOSC bool, err error) {
-	start, err := o.readNextByte()
+func (o *Output) readNextResponse(tty io.ReadWriter) (response string, isOSC bool, err error) {
+	start, err := o.readNextByte(tty)
 	if err != nil {
 		return "", false, err
 	}
 
 	// first byte must be ESC
 	for start != ESC {
-		start, err = o.readNextByte()
+		start, err = o.readNextByte(tty)
 		if err != nil {
 			return "", false, err
 		}
@@ -173,7 +173,7 @@ func (o *Output) readNextResponse() (response string, isOSC bool, err error) {
 	response += string(start)
 
 	// next byte is either '[' (cursor position response) or ']' (OSC response)
-	tpe, err := o.readNextByte()
+	tpe, err := o.readNextByte(tty)
 	if err != nil {
 		return "", false, err
 	}
@@ -191,7 +191,7 @@ func (o *Output) readNextResponse() (response string, isOSC bool, err error) {
 	}
 
 	for {
-		b, err := o.readNextByte()
+		b, err := o.readNextByte(tty)
 		if err != nil {
 			return "", false, err
 		}
@@ -227,13 +227,17 @@ func (o Output) termStatusReport(sequence int) (string, error) {
 		return "", ErrStatusReport
 	}
 
-	tty := o.TTY()
-	if tty == nil {
+	tty, ok := o.TTY().(io.ReadWriter)
+	if tty == nil || !ok {
 		return "", ErrStatusReport
 	}
 
 	if !o.unsafe {
-		fd := int(tty.Fd())
+		f, ok := tty.(File)
+		if !ok {
+			return "", ErrStatusReport
+		}
+		fd := int(f.Fd())
 		// if in background, we can't control the terminal
 		if !isForeground(fd) {
 			return "", ErrStatusReport
@@ -260,7 +264,7 @@ func (o Output) termStatusReport(sequence int) (string, error) {
 	fmt.Fprintf(tty, CSI+"6n")
 
 	// read the next response
-	res, isOSC, err := o.readNextResponse()
+	res, isOSC, err := o.readNextResponse(tty)
 	if err != nil {
 		return "", fmt.Errorf("%s: %s", ErrStatusReport, err)
 	}
@@ -271,7 +275,7 @@ func (o Output) termStatusReport(sequence int) (string, error) {
 	}
 
 	// read the cursor query response next and discard the result
-	_, _, err = o.readNextResponse()
+	_, _, err = o.readNextResponse(tty)
 	if err != nil {
 		return "", err
 	}

termenv_windows.go

@@ -103,8 +103,8 @@ func EnableVirtualTerminalProcessing(o *Output) (restoreFunc func() error, err e
 	}
 
 	// If o is not a tty, then there is nothing to do.
-	tty := o.TTY()
-	if tty == nil {
+	tty, ok := o.TTY().(File)
+	if tty == nil || !ok {
 		return
 	}