Update vendoring via vndr

gateway/vendor/github.com/Azure/go-ansiterm/escape_state.go

@@ -0,0 +1,47 @@
+package ansiterm
+
+type escapeState struct {
+	baseState
+}
+
+func (escState escapeState) Handle(b byte) (s state, e error) {
+	logger.Infof("escapeState::Handle %#x", b)
+	nextState, err := escState.baseState.Handle(b)
+	if nextState != nil || err != nil {
+		return nextState, err
+	}
+
+	switch {
+	case b == ANSI_ESCAPE_SECONDARY:
+		return escState.parser.csiEntry, nil
+	case b == ANSI_OSC_STRING_ENTRY:
+		return escState.parser.oscString, nil
+	case sliceContains(executors, b):
+		return escState, escState.parser.execute()
+	case sliceContains(escapeToGroundBytes, b):
+		return escState.parser.ground, nil
+	case sliceContains(intermeds, b):
+		return escState.parser.escapeIntermediate, nil
+	}
+
+	return escState, nil
+}
+
+func (escState escapeState) Transition(s state) error {
+	logger.Infof("Escape::Transition %s --> %s", escState.Name(), s.Name())
+	escState.baseState.Transition(s)
+
+	switch s {
+	case escState.parser.ground:
+		return escState.parser.escDispatch()
+	case escState.parser.escapeIntermediate:
+		return escState.parser.collectInter()
+	}
+
+	return nil
+}
+
+func (escState escapeState) Enter() error {
+	escState.parser.clear()
+	return nil
+}