Update to last common bleve (#3986)

vendor/github.com/mschoch/smat/actionseq.go

@@ -0,0 +1,61 @@
+//  Copyright (c) 2016 Marty Schoch
+
+//  Licensed under the Apache License, Version 2.0 (the "License");
+//  you may not use this file except in compliance with the
+//  License. You may obtain a copy of the License at
+//    http://www.apache.org/licenses/LICENSE-2.0
+//  Unless required by applicable law or agreed to in writing,
+//  software distributed under the License is distributed on an "AS
+//  IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+//  express or implied. See the License for the specific language
+//  governing permissions and limitations under the License.
+
+package smat
+
+// ActionSeq represents a sequence of actions, used for populating a corpus
+// of byte sequences for the corresponding fuzz tests
+type ActionSeq []ActionID
+
+// ByteEncoding runs the FSM to produce a byte sequence to trigger the
+// desired action
+func (a ActionSeq) ByteEncoding(ctx Context, setup, teardown ActionID, actionMap ActionMap) ([]byte, error) {
+	setupFunc, teardownFunc, err := actionMap.findSetupTeardown(setup, teardown)
+	if err != nil {
+		return nil, err
+	}
+	state, err := setupFunc(ctx)
+	if err != nil {
+		return nil, err
+	}
+	defer func() {
+		_, _ = teardownFunc(ctx)
+	}()
+
+	var rv []byte
+	for _, actionID := range a {
+		b, err := probeStateForAction(state, actionID)
+		if err != nil {
+			return nil, err
+		}
+		rv = append(rv, b)
+		action, ok := actionMap[actionID]
+		if !ok {
+			continue
+		}
+		state, err = action(ctx)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return rv, nil
+}
+
+func probeStateForAction(state State, actionID ActionID) (byte, error) {
+	for i := 0; i < 256; i++ {
+		nextActionID := state(byte(i))
+		if nextActionID == actionID {
+			return byte(i), nil
+		}
+	}
+	return 0, ErrActionNotPossible
+}