use net.ErrClosed (for Go 1.16)

internal/qerr/errors_not_go116.go

@@ -0,0 +1,33 @@
+// +build !go1.16
+
+package qerr
+
+func (e *TransportError) Is(target error) bool {
+	_, ok := target.(*TransportError)
+	return ok
+}
+
+func (e *ApplicationError) Is(target error) bool {
+	_, ok := target.(*ApplicationError)
+	return ok
+}
+
+func (e *IdleTimeoutError) Is(target error) bool {
+	_, ok := target.(*IdleTimeoutError)
+	return ok
+}
+
+func (e *HandshakeTimeoutError) Is(target error) bool {
+	_, ok := target.(*HandshakeTimeoutError)
+	return ok
+}
+
+func (e *VersionNegotiationError) Is(target error) bool {
+	_, ok := target.(*VersionNegotiationError)
+	return ok
+}
+
+func (e *StatelessResetError) Is(target error) bool {
+	_, ok := target.(*StatelessResetError)
+	return ok
+}