text: // Copyright 2016 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #include "net/cert/merkle_audit_proof.h"
  
  #include "base/check.h"
  #include "testing/gmock/include/gmock/gmock.h"
  #include "testing/gtest/include/gtest/gtest.h"
  
  namespace net {
  namespace ct {
  namespace {
  
  TEST(MerkleAuditProofTest, CalculatesAuditPathLengthCorrectly) {
    // Test all leaves up to a tree size of 4:
    EXPECT_EQ(0u, CalculateAuditPathLength(0, 1));
    EXPECT_EQ(1u, CalculateAuditPathLength(0, 2));
    EXPECT_EQ(1u, CalculateAuditPathLength(1, 2));
    EXPECT_EQ(2u, CalculateAuditPathLength(0, 3));
    EXPECT_EQ(2u, CalculateAuditPathLength(1, 3));
    EXPECT_EQ(1u, CalculateAuditPathLength(2, 3));
    EXPECT_EQ(2u, CalculateAuditPathLength(0, 4));
    EXPECT_EQ(2u, CalculateAuditPathLength(1, 4));
    EXPECT_EQ(2u, CalculateAuditPathLength(2, 4));
    EXPECT_EQ(2u, CalculateAuditPathLength(3, 4));
    // Boundary cases for a larger tree size:
    EXPECT_EQ(9u, CalculateAuditPathLength(0, 257));
    EXPECT_EQ(9u, CalculateAuditPathLength(255, 257));
    EXPECT_EQ(1u, CalculateAuditPathLength(256, 257));
    // Example from CT over DNS draft RFC:
    EXPECT_EQ(20u, CalculateAuditPathLength(123456, 999999));
    // Test data from
    // https://github.com/google/certificate-transparency/blob/af98904302724c29aa6659ca372d41c9687de2b7/python/ct/crypto/merkle_test.py:
    EXPECT_EQ(22u, CalculateAuditPathLength(848049, 3630887));
  }
  
  TEST(MerkleAuditProofDeathTest, DiesIfLeafIndexIsGreaterThanOrEqualToTreeSize) {
  #ifdef OFFICIAL_BUILD
    // The official build does not print the reason a CHECK failed.
    const char kErrorRegex[] = "";
  #else
    const char kErrorRegex[] = "leaf_index < tree_size";
  #endif
  
    EXPECT_DEATH_IF_SUPPORTED(CalculateAuditPathLength(0, 0), kErrorRegex);
    EXPECT_DEATH_IF_SUPPORTED(CalculateAuditPathLength(10, 10), kErrorRegex);
    EXPECT_DEATH_IF_SUPPORTED(CalculateAuditPathLength(11, 10), kErrorRegex);
  }
  
  }  // namespace
  }  // namespace ct
  }  // namespace net
  