Googletest export

googletest/include/gtest/internal/gtest-internal.h

@@ -159,15 +159,15 @@ GTEST_DISABLE_MSC_WARNINGS_POP_()  //  4275
 
 #endif  // GTEST_HAS_EXCEPTIONS
 
+namespace edit_distance {
 // Returns the optimal edits to go from 'left' to 'right'.
 // All edits cost the same, with replace having lower priority than
-// add/remove. Returns an approximation of the maximum memory used in
-// 'memory_usage' if non-null.
-// Uses a Dijkstra search, with a couple of simple bells and whistles added on.
-enum EditType { kEditMatch, kEditAdd, kEditRemove, kEditReplace };
+// add/remove.
+// Simple implementation of the Wagner-Fischer algorithm.
+// See http://en.wikipedia.org/wiki/Wagner-Fischer_algorithm
+enum EditType { kMatch, kAdd, kRemove, kReplace };
 GTEST_API_ std::vector<EditType> CalculateOptimalEdits(
-    const std::vector<size_t>& left, const std::vector<size_t>& right,
-    size_t* memory_usage = NULL);
+    const std::vector<size_t>& left, const std::vector<size_t>& right);
 
 // Same as above, but the input is represented as strings.
 GTEST_API_ std::vector<EditType> CalculateOptimalEdits(
@@ -179,6 +179,8 @@ GTEST_API_ std::string CreateUnifiedDiff(const std::vector<std::string>& left,
                                          const std::vector<std::string>& right,
                                          size_t context = 2);
 
+}  // namespace edit_distance
+
 // Calculate the diff between 'left' and 'right' and return it in unified diff
 // format.
 // If not null, stores in 'total_line_count' the total number of lines found

googletest/src/gtest-all.cc

@@ -38,11 +38,10 @@
 #include "gtest/gtest.h"
 
 // The following lines pull in the real gtest *.cc files.
+#include "src/gtest.cc"
 #include "src/gtest-death-test.cc"
-#include "src/gtest-edit-distance.cc"
 #include "src/gtest-filepath.cc"
 #include "src/gtest-port.cc"
 #include "src/gtest-printers.cc"
 #include "src/gtest-test-part.cc"
 #include "src/gtest-typed-test.cc"
-#include "src/gtest.cc"

googletest/src/gtest.cc

@@ -46,6 +46,7 @@
 #include <algorithm>
 #include <iomanip>
 #include <limits>
+#include <list>
 #include <map>
 #include <ostream>  // NOLINT
 #include <sstream>
@@ -1067,6 +1068,246 @@ AssertionResult AssertionFailure(const Message& message) {
 
 namespace internal {
 
+namespace edit_distance {
+std::vector<EditType> CalculateOptimalEdits(const std::vector<size_t>& left,
+                                            const std::vector<size_t>& right) {
+  std::vector<std::vector<double> > costs(
+      left.size() + 1, std::vector<double>(right.size() + 1));
+  std::vector<std::vector<EditType> > best_move(
+      left.size() + 1, std::vector<EditType>(right.size() + 1));
+
+  // Populate for empty right.
+  for (size_t l_i = 0; l_i < costs.size(); ++l_i) {
+    costs[l_i][0] = static_cast<double>(l_i);
+    best_move[l_i][0] = kRemove;
+  }
+  // Populate for empty left.
+  for (size_t r_i = 1; r_i < costs[0].size(); ++r_i) {
+    costs[0][r_i] = static_cast<double>(r_i);
+    best_move[0][r_i] = kAdd;
+  }
+
+  for (size_t l_i = 0; l_i < left.size(); ++l_i) {
+    for (size_t r_i = 0; r_i < right.size(); ++r_i) {
+      if (left[l_i] == right[r_i]) {
+        // Found a match. Consume it.
+        costs[l_i + 1][r_i + 1] = costs[l_i][r_i];
+        best_move[l_i + 1][r_i + 1] = kMatch;
+        continue;
+      }
+
+      const double add = costs[l_i + 1][r_i];
+      const double remove = costs[l_i][r_i + 1];
+      const double replace = costs[l_i][r_i];
+      if (add < remove && add < replace) {
+        costs[l_i + 1][r_i + 1] = add + 1;
+        best_move[l_i + 1][r_i + 1] = kAdd;
+      } else if (remove < add && remove < replace) {
+        costs[l_i + 1][r_i + 1] = remove + 1;
+        best_move[l_i + 1][r_i + 1] = kRemove;
+      } else {
+        // We make replace a little more expensive than add/remove to lower
+        // their priority.
+        costs[l_i + 1][r_i + 1] = replace + 1.00001;
+        best_move[l_i + 1][r_i + 1] = kReplace;
+      }
+    }
+  }
+
+  // Reconstruct the best path. We do it in reverse order.
+  std::vector<EditType> best_path;
+  for (size_t l_i = left.size(), r_i = right.size(); l_i > 0 || r_i > 0;) {
+    EditType move = best_move[l_i][r_i];
+    best_path.push_back(move);
+    l_i -= move != kAdd;
+    r_i -= move != kRemove;
+  }
+  std::reverse(best_path.begin(), best_path.end());
+  return best_path;
+}
+
+namespace {
+
+// Helper class to convert string into ids with deduplication.
+class InternalStrings {
+ public:
+  size_t GetId(const std::string& str) {
+    IdMap::iterator it = ids_.find(str);
+    if (it != ids_.end()) return it->second;
+    size_t id = ids_.size();
+    return ids_[str] = id;
+  }
+
+ private:
+  typedef std::map<std::string, size_t> IdMap;
+  IdMap ids_;
+};
+
+}  // namespace
+
+std::vector<EditType> CalculateOptimalEdits(
+    const std::vector<std::string>& left,
+    const std::vector<std::string>& right) {
+  std::vector<size_t> left_ids, right_ids;
+  {
+    InternalStrings intern_table;
+    for (size_t i = 0; i < left.size(); ++i) {
+      left_ids.push_back(intern_table.GetId(left[i]));
+    }
+    for (size_t i = 0; i < right.size(); ++i) {
+      right_ids.push_back(intern_table.GetId(right[i]));
+    }
+  }
+  return CalculateOptimalEdits(left_ids, right_ids);
+}
+
+namespace {
+
+// Helper class that holds the state for one hunk and prints it out to the
+// stream.
+// It reorders adds/removes when possible to group all removes before all
+// adds. It also adds the hunk header before printint into the stream.
+class Hunk {
+ public:
+  Hunk(size_t left_start, size_t right_start)
+      : left_start_(left_start),
+        right_start_(right_start),
+        adds_(),
+        removes_(),
+        common_() {}
+
+  void PushLine(char edit, const char* line) {
+    switch (edit) {
+      case ' ':
+        ++common_;
+        FlushEdits();
+        hunk_.push_back(std::make_pair(' ', line));
+        break;
+      case '-':
+        ++removes_;
+        hunk_removes_.push_back(std::make_pair('-', line));
+        break;
+      case '+':
+        ++adds_;
+        hunk_adds_.push_back(std::make_pair('+', line));
+        break;
+    }
+  }
+
+  void PrintTo(std::ostream* os) {
+    PrintHeader(os);
+    FlushEdits();
+    for (std::list<std::pair<char, const char*> >::const_iterator it =
+             hunk_.begin();
+         it != hunk_.end(); ++it) {
+      *os << it->first << it->second << "\n";
+    }
+  }
+
+  bool has_edits() const { return adds_ || removes_; }
+
+ private:
+  void FlushEdits() {
+    hunk_.splice(hunk_.end(), hunk_removes_);
+    hunk_.splice(hunk_.end(), hunk_adds_);
+  }
+
+  // Print a unified diff header for one hunk.
+  // The format is
+  //   "@@ -<left_start>,<left_length> +<right_start>,<right_length> @@"
+  // where the left/right parts are omitted if unnecessary.
+  void PrintHeader(std::ostream* ss) const {
+    *ss << "@@ ";
+    if (removes_) {
+      *ss << "-" << left_start_ << "," << (removes_ + common_);
+    }
+    if (removes_ && adds_) {
+      *ss << " ";
+    }
+    if (adds_) {
+      *ss << "+" << right_start_ << "," << (adds_ + common_);
+    }
+    *ss << " @@\n";
+  }
+
+  size_t left_start_, right_start_;
+  size_t adds_, removes_, common_;
+  std::list<std::pair<char, const char*> > hunk_, hunk_adds_, hunk_removes_;
+};
+
+}  // namespace
+
+// Create a list of diff hunks in Unified diff format.
+// Each hunk has a header generated by PrintHeader above plus a body with
+// lines prefixed with ' ' for no change, '-' for deletion and '+' for
+// addition.
+// 'context' represents the desired unchanged prefix/suffix around the diff.
+// If two hunks are close enough that their contexts overlap, then they are
+// joined into one hunk.
+std::string CreateUnifiedDiff(const std::vector<std::string>& left,
+                              const std::vector<std::string>& right,
+                              size_t context) {
+  const std::vector<EditType> edits = CalculateOptimalEdits(left, right);
+
+  size_t l_i = 0, r_i = 0, edit_i = 0;
+  std::stringstream ss;
+  while (edit_i < edits.size()) {
+    // Find first edit.
+    while (edit_i < edits.size() && edits[edit_i] == kMatch) {
+      ++l_i;
+      ++r_i;
+      ++edit_i;
+    }
+
+    // Find the first line to include in the hunk.
+    const size_t prefix_context = std::min(l_i, context);
+    Hunk hunk(l_i - prefix_context + 1, r_i - prefix_context + 1);
+    for (size_t i = prefix_context; i > 0; --i) {
+      hunk.PushLine(' ', left[l_i - i].c_str());
+    }
+
+    // Iterate the edits until we found enough suffix for the hunk or the input
+    // is over.
+    size_t n_suffix = 0;
+    for (; edit_i < edits.size(); ++edit_i) {
+      if (n_suffix >= context) {
+        // Continue only if the next hunk is very close.
+        std::vector<EditType>::const_iterator it = edits.begin() + edit_i;
+        while (it != edits.end() && *it == kMatch) ++it;
+        if (it == edits.end() || (it - edits.begin()) - edit_i >= context) {
+          // There is no next edit or it is too far away.
+          break;
+        }
+      }
+
+      EditType edit = edits[edit_i];
+      // Reset count when a non match is found.
+      n_suffix = edit == kMatch ? n_suffix + 1 : 0;
+
+      if (edit == kMatch || edit == kRemove || edit == kReplace) {
+        hunk.PushLine(edit == kMatch ? ' ' : '-', left[l_i].c_str());
+      }
+      if (edit == kAdd || edit == kReplace) {
+        hunk.PushLine('+', right[r_i].c_str());
+      }
+
+      // Advance indices, depending on edit type.
+      l_i += edit != kAdd;
+      r_i += edit != kRemove;
+    }
+
+    if (!hunk.has_edits()) {
+      // We are done. We don't want this hunk.
+      break;
+    }
+
+    hunk.PrintTo(&ss);
+  }
+  return ss.str();
+}
+
+}  // namespace edit_distance
+
 namespace {
 
 // The string representation of the values received in EqFailure() are already
@@ -1138,7 +1379,8 @@ AssertionResult EqFailure(const char* lhs_expression,
     const std::vector<std::string> rhs_lines =
         SplitEscapedString(rhs_value);
     if (lhs_lines.size() > 1 || rhs_lines.size() > 1) {
-      msg << "\nWith diff:\n" << CreateUnifiedDiff(lhs_lines, rhs_lines);
+      msg << "\nWith diff:\n"
+          << edit_distance::CreateUnifiedDiff(lhs_lines, rhs_lines);
     }
   }
 

googletest/test/gtest_unittest.cc

@@ -215,7 +215,6 @@ using testing::GTEST_FLAG(stream_result_to);
 using testing::GTEST_FLAG(throw_on_failure);
 using testing::IsNotSubstring;
 using testing::IsSubstring;
-using testing::kMaxStackTraceDepth;
 using testing::Message;
 using testing::ScopedFakeTestPartResultReporter;
 using testing::StaticAssertTypeEq;
@@ -235,18 +234,16 @@ using testing::internal::AlwaysTrue;
 using testing::internal::AppendUserMessage;
 using testing::internal::ArrayAwareFind;
 using testing::internal::ArrayEq;
-using testing::internal::CalculateOptimalEdits;
 using testing::internal::CodePointToUtf8;
 using testing::internal::CompileAssertTypesEqual;
 using testing::internal::CopyArray;
 using testing::internal::CountIf;
-using testing::internal::CreateUnifiedDiff;
-using testing::internal::EditType;
 using testing::internal::EqFailure;
 using testing::internal::FloatingPoint;
 using testing::internal::ForEach;
 using testing::internal::FormatEpochTimeInMillisAsIso8601;
 using testing::internal::FormatTimeInMillisAsSeconds;
+using testing::internal::GTestFlagSaver;
 using testing::internal::GetCurrentOsStackTraceExceptTop;
 using testing::internal::GetElementOr;
 using testing::internal::GetNextRandomSeed;
@@ -255,7 +252,6 @@ using testing::internal::GetTestTypeId;
 using testing::internal::GetTimeInMillis;
 using testing::internal::GetTypeId;
 using testing::internal::GetUnitTestImpl;
-using testing::internal::GTestFlagSaver;
 using testing::internal::ImplicitlyConvertible;
 using testing::internal::Int32;
 using testing::internal::Int32FromEnvOrDie;
@@ -263,8 +259,6 @@ using testing::internal::IsAProtocolMessage;
 using testing::internal::IsContainer;
 using testing::internal::IsContainerTest;
 using testing::internal::IsNotContainer;
-using testing::internal::kMaxRandomSeed;
-using testing::internal::kTestTypeIdInGoogleTest;
 using testing::internal::NativeArray;
 using testing::internal::OsStackTraceGetter;
 using testing::internal::OsStackTraceGetterInterface;
@@ -286,6 +280,12 @@ using testing::internal::TestResultAccessor;
 using testing::internal::UInt32;
 using testing::internal::UnitTestImpl;
 using testing::internal::WideStringToUtf8;
+using testing::internal::edit_distance::CalculateOptimalEdits;
+using testing::internal::edit_distance::CreateUnifiedDiff;
+using testing::internal::edit_distance::EditType;
+using testing::internal::kMaxRandomSeed;
+using testing::internal::kTestTypeIdInGoogleTest;
+using testing::kMaxStackTraceDepth;
 
 #if GTEST_HAS_STREAM_REDIRECTION
 using testing::internal::CaptureStdout;
@@ -3517,14 +3517,14 @@ TEST(EditDistance, TestCases) {
       {__LINE__, "ABCD", "abcd", "////",
        "@@ -1,4 +1,4 @@\n-A\n-B\n-C\n-D\n+a\n+b\n+c\n+d\n"},
       // Path finding.
-      {__LINE__, "ABCDEFGH", "ABXEGH1", "  /- -  +",
+      {__LINE__, "ABCDEFGH", "ABXEGH1", "  -/ -  +",
        "@@ -1,8 +1,7 @@\n A\n B\n-C\n-D\n+X\n E\n-F\n G\n H\n+1\n"},
-      {__LINE__, "AAAABCCCC", "ABABCDCDC", " -/   + / ",
-       "@@ -1,9 +1,9 @@\n A\n-A\n-A\n+B\n A\n B\n C\n+D\n C\n-C\n+D\n C\n"},
-      {__LINE__, "ABCDE", "BCDCD", "-   /+",
+      {__LINE__, "AAAABCCCC", "ABABCDCDC", "- /   + / ",
+       "@@ -1,9 +1,9 @@\n-A\n A\n-A\n+B\n A\n B\n C\n+D\n C\n-C\n+D\n C\n"},
+      {__LINE__, "ABCDE", "BCDCD", "-   +/",
        "@@ -1,5 +1,5 @@\n-A\n B\n C\n D\n-E\n+C\n+D\n"},
-      {__LINE__, "ABCDEFGHIJKL", "BGDCDEFGJKLJK", "- ++     --   ++",
-       "@@ -1,4 +1,5 @@\n-A\n B\n+G\n+D\n C\n D\n"
+      {__LINE__, "ABCDEFGHIJKL", "BCDCDEFGJKLJK", "- ++     --   ++",
+       "@@ -1,4 +1,5 @@\n-A\n B\n+C\n+D\n C\n D\n"
        "@@ -6,7 +7,7 @@\n F\n G\n-H\n-I\n J\n K\n L\n+J\n+K\n"},
       {}};
   for (const Case* c = kCases; c->left; ++c) {
@@ -3542,57 +3542,6 @@ TEST(EditDistance, TestCases) {
   }
 }
 
-// Tests that we can run CalculateOptimalEdits for a large vector, i.e. we can
-// compute diffs for large strings.
-TEST(EditDistance, LargeVectorWithDiffs) {
-  const int kSize = 300000;
-  std::vector<size_t> left;
-  std::vector<size_t> right;
-  std::vector<EditType> expected(kSize, testing::internal::kEditMatch);
-
-  left.reserve(kSize);
-  right.reserve(kSize);
-  for (int i = 0; i < kSize; ++i) {
-    // Make the contents of the vectors unique. This greatly speeds up
-    // the algorithm, since it doesn't spend time finding matches for
-    // different alignments.
-    left.push_back(i);
-    right.push_back(i);
-  }
-
-  for (int i = 0; i < 10; ++i) {
-    right[i] = kSize + i;
-    expected[i] = testing::internal::kEditReplace;
-    right[kSize - i - 1] = kSize * 2 + i;
-    expected[kSize - i - 1] = testing::internal::kEditReplace;
-  }
-  size_t memory_usage;
-  EXPECT_EQ(CalculateOptimalEdits(left, right, &memory_usage), expected);
-  EXPECT_GT(memory_usage, kSize);
-  EXPECT_LT(memory_usage, kSize * 2);
-}
-
-// Tests that we can run CalculateOptimalEdits for two vectors N and M, where
-// M = N plus additional junk at the end. The current algorithm only does O(M)
-// "real" work in this case, but allocates some extra memory. We test that this
-// is still fast enough for common cases, and we aren't allocating an
-// excessive amount of extra memory.
-TEST(EditDistance, LargeVectorWithTrailingJunk) {
-  const int kSize = 200000;
-  const int kAdditionalSize = 2000;
-  std::vector<size_t> left(kSize, 0);
-  std::vector<size_t> right(kSize + kAdditionalSize, 0);
-  std::vector<EditType> expected(kSize + kAdditionalSize,
-                                 testing::internal::kEditMatch);
-  for (int i = 0; i < kAdditionalSize; ++i) {
-    expected[i + kSize] = testing::internal::kEditAdd;
-  }
-  size_t memory_usage;
-  EXPECT_EQ(CalculateOptimalEdits(left, right, &memory_usage), expected);
-  EXPECT_GT(memory_usage, kSize);
-  EXPECT_LT(memory_usage, 6000000);
-}
-
 // Tests EqFailure(), used for implementing *EQ* assertions.
 TEST(AssertionTest, EqFailure) {
   const std::string foo_val("5"), bar_val("6");