content: /*
   * Copyright (c) 2013 - 2014, Allen A. George <allen dot george at gmail dot com>
   *
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   *     * Redistributions of source code must retain the above copyright
   *       notice, this list of conditions and the following disclaimer.
   *     * Redistributions in binary form must reproduce the above copyright
   *       notice, this list of conditions and the following disclaimer in the
   *       documentation and/or other materials provided with the distribution.
   *     * Neither the name of libraft nor the
   *       names of its contributors may be used to endorse or promote products
   *       derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
   * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
   * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
   * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  package io.libraft.algorithm;
  
  import io.libraft.Command;
  
  import static com.google.common.base.Preconditions.checkArgument;
  import static com.google.common.base.Preconditions.checkNotNull;
  import static org.hamcrest.MatcherAssert.assertThat;
  import static org.hamcrest.Matchers.equalTo;
  import static org.hamcrest.Matchers.notNullValue;
  import static org.hamcrest.Matchers.nullValue;
  import static org.hamcrest.Matchers.theInstance;
  
  abstract class UnitTestLogEntries {
  
      protected UnitTestLogEntries() { } // private to prevent instantiation
  
      //================================================================================================================//
      //
      // Convenience Constructors
      //
      //================================================================================================================//
  
      @SuppressWarnings("SameReturnValue")
      static LogEntry SENTINEL() {
          return LogEntry.SENTINEL;
      }
  
      static LogEntry.NoopEntry NOOP(long index, long term) {
          return new LogEntry.NoopEntry(index, term);
      }
  
      static LogEntry.ClientEntry CLIENT(long index, long term, Command command) {
          return new LogEntry.ClientEntry(index, term, command);
      }
  
      //================================================================================================================//
      //
      // Manipulation
      //
      //================================================================================================================//
  
      static void clearLog(Log log) throws StorageException {
          log.truncate(0);
      }
  
      static void insertIntoLog(Log log, LogEntry... entries) throws StorageException {
          checkArgument(entries.length > 0);
  
          for (LogEntry entry : entries) {
              log.put(entry);
          }
      }
  
      //================================================================================================================//
      //
      // Asserts
      //
      //================================================================================================================//
  
      static void assertThatLogIsEmpty(Log log) throws StorageException {
          LogEntry lastLog = log.getLast();
          assertThat(lastLog, nullValue());
      }
  
      static void assertThatLogContainsOnlySentinel(Log log) throws StorageException {
          LogEntry lastLog = log.getLast();
          assertThat(lastLog, notNullValue());
          assertThat(lastLog, theInstance(SENTINEL()));
      }
  
      static void assertThatLogContains(Log log, LogEntry... entries) throws StorageException {
          entries = checkNotNull(entries);
          checkArgument(entries.length > 0);
  
          // ensure that all the log entries before the first given entry are null (i.e. don't exist)
          long entryIndex = entries[0].getIndex();
          for (int i = 0; i < entryIndex; i++) {
              assertThat(log.get(i), nullValue());
          }
  
          // all the entries in the log match those we're asked to compare against
          for(LogEntry entry : entries) {
              assertThat(entry, equalTo(log.get(entryIndex++)));
          }
  
          // the last entry in the log is the last one given to us
          // note that this will always be valid because we'll always have
          // at least one entry to compare in the foreach above
          assertThat(log.getLast().getIndex() + 1, equalTo(entryIndex));
      }
  }
  