diff options
Diffstat (limited to 'googletest/src/gtest.cc')
| -rw-r--r-- | googletest/src/gtest.cc | 244 |
1 files changed, 243 insertions, 1 deletions
diff --git a/googletest/src/gtest.cc b/googletest/src/gtest.cc index ba706c1..9796637 100644 --- a/googletest/src/gtest.cc +++ b/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); } } |