gtest-param-util.h

Search s framework 老外写的

// Copyright 2008 Google Inc.
// 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 Google Inc. 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
// OWNER 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.
//
// Author: [e-mail] (Vlad Losev)

// Type and function utilities for implementing parameterized tests.

#ifndef GTEST_INCLUDE_GTEST_INTERNAL_GTEST_PARAM_UTIL_H_
#define GTEST_INCLUDE_GTEST_INTERNAL_GTEST_PARAM_UTIL_H_

#include <iterator>
#include <utility>
#include <vector>

#include <gtest/internal/gtest-port.h>

#ifdef GTEST_HAS_PARAM_TEST

#if GTEST_HAS_RTTI
#include <typeinfo>
#endif  // GTEST_HAS_RTTI

#include <gtest/internal/gtest-linked_ptr.h>
#include <gtest/internal/gtest-internal.h>

namespace testing {
namespace internal {

// INTERNAL IMPLEMENTATION - DO NOT USE IN USER CODE.
//
// Outputs a message explaining invalid registration of different
// fixture class for the same test case. This may happen when
// TEST_P macro is used to define two tests with the same name
// but in different namespaces.
void ReportInvalidTestCaseType(const char* test_case_name,
                               const char* file, int line);

// INTERNAL IMPLEMENTATION - DO NOT USE IN USER CODE.
//
// Downcasts the pointer of type Base to Derived.
// Derived must be a subclass of Base. The parameter MUST
// point to a class of type Derived, not any subclass of it.
// When RTTI is available, the function performs a runtime
// check to enforce this.
template <class Derived, class Base>
Derived* CheckedDowncastToActualType(Base* base) {
#if GTEST_HAS_RTTI
  GTEST_CHECK_(typeid(*base) == typeid(Derived));
  Derived* derived = dynamic_cast<Derived*>(base);  // NOLINT
#else
  Derived* derived = static_cast<Derived*>(base);  // Poor man's downcast.
#endif  // GTEST_HAS_RTTI
  return derived;
}

template <typename> class ParamGeneratorInterface;
template <typename> class ParamGenerator;

// Interface for iterating over elements provided by an implementation
// of ParamGeneratorInterface<T>.
template <typename T>
class ParamIteratorInterface {
 public:
  virtual ~ParamIteratorInterface() {}
  // A pointer to the base generator instance.
  // Used only for the purposes of iterator comparison
  // to make sure that two iterators belong to the same generator.
  virtual const ParamGeneratorInterface<T>* BaseGenerator() const = 0;
  // Advances iterator to point to the next element
  // provided by the generator. The caller is responsible
  // for not calling Advance() on an iterator equal to
  // BaseGenerator()->End().
  virtual void Advance() = 0;
  // Clones the iterator object. Used for implementing copy semantics
  // of ParamIterator<T>.
  virtual ParamIteratorInterface* Clone() const = 0;
  // Dereferences the current iterator and provides (read-only) access
  // to the pointed value. It is the caller's responsibility not to call
  // Current() on an iterator equal to BaseGenerator()->End().
  // Used for implementing ParamGenerator<T>::operator*().
  virtual const T* Current() const = 0;
  // Determines whether the given iterator and other point to the same
  // element in the sequence generated by the generator.
  // Used for implementing ParamGenerator<T>::operator==().
  virtual bool Equals(const ParamIteratorInterface& other) const = 0;
};

// Class iterating over elements provided by an implementation of
// ParamGeneratorInterface<T>. It wraps ParamIteratorInterface<T>
// and implements the const forward iterator concept.
template <typename T>
class ParamIterator {
 public:
  typedef T value_type;
  typedef const T& reference;
  typedef ptrdiff_t difference_type;

  // ParamIterator assumes ownership of the impl_ pointer.
  ParamIterator(const ParamIterator& other) : impl_(other.impl_->Clone()) {}
  ParamIterator& operator=(const ParamIterator& other) {
    if (this != &other)
      impl_.reset(other.impl_->Clone());
    return *this;
  }

  const T& operator*() const { return *impl_->Current(); }
  const T* operator->() const { return impl_->Current(); }
  // Prefix version of operator++.
  ParamIterator& operator++() {
    impl_->Advance();
    return *this;
  }
  // Postfix version of operator++.
  ParamIterator operator++(int /*unused*/) {
    ParamIteratorInterface<T>* clone = impl_->Clone();
    impl_->Advance();
    return ParamIterator(clone);
  }
  bool operator==(const ParamIterator& other) const {
    return impl_.get() == other.impl_.get() || impl_->Equals(*other.impl_);
  }
  bool operator!=(const ParamIterator& other) const {
    return !(*this == other);
  }

 private:
  friend class ParamGenerator<T>;
  explicit ParamIterator(ParamIteratorInterface<T>* impl) : impl_(impl) {}
  scoped_ptr<ParamIteratorInterface<T> > impl_;
};

// ParamGeneratorInterface<T> is the binary interface to access generators
// defined in other translation units.
template <typename T>
class ParamGeneratorInterface {
 public:
  typedef T ParamType;

  virtual ~ParamGeneratorInterface() {}

  // Generator interface definition
  virtual ParamIteratorInterface<T>* Begin() const = 0;
  virtual ParamIteratorInterface<T>* End() const = 0;
};

// Wraps ParamGeneratorInetrface<T> and provides general generator syntax
// compatible with the STL Container concept.
// This class implements copy initialization semantics and the contained
// ParamGeneratorInterface<T> instance is shared among all copies
// of the original object. This is possible because that instance is immutable.
template<typename T>
class ParamGenerator {
 public:
  typedef ParamIterator<T> iterator;

  explicit ParamGenerator(ParamGeneratorInterface<T>* impl) : impl_(impl) {}
  ParamGenerator(const ParamGenerator& other) : impl_(other.impl_) {}

  ParamGenerator& operator=(const ParamGenerator& other) {
    impl_ = other.impl_;
    return *this;
  }

  iterator begin() const { return iterator(impl_->Begin()); }
  iterator end() const { return iterator(impl_->End()); }

 private:
  ::testing::internal::linked_ptr<const ParamGeneratorInterface<T> > impl_;
};

// Generates values from a range of two comparable values. Can be used to
// generate sequences of user-defined types that implement operator+() and
// operator<().
// This class is used in the Range() function.
template <typename T, typename IncrementT>
class RangeGenerator : public ParamGeneratorInterface<T> {
 public:
  RangeGenerator(T begin, T end, IncrementT step)
      : begin_(begin), end_(end),
        step_(step), end_index_(CalculateEndIndex(begin, end, step)) {}
  virtual ~RangeGenerator() {}

  virtual ParamIteratorInterface<T>* Begin() const {
    return new Iterator(this, begin_, 0, step_);
  }
  virtual ParamIteratorInterface<T>* End() const {
    return new Iterator(this, end_, end_index_, step_);
  }

 private:
  class Iterator : public ParamIteratorInterface<T> {
   public:
    Iterator(const ParamGeneratorInterface<T>* base, T value, int index,
             IncrementT step)
        : base_(base), value_(value), index_(index), step_(step) {}
    virtual ~Iterator() {}

    virtual const ParamGeneratorInterface<T>* BaseGenerator() const {
      return base_;
    }
    virtual void Advance() {
      value_ = value_ + step_;
      index_++;
    }
    virtual ParamIteratorInterface<T>* Clone() const {
      return new Iterator(*this);
    }
    virtual const T* Current() const { return &value_; }
    virtual bool Equals(const ParamIteratorInterface<T>& other) const {
      // Having the same base generator guarantees that the other
      // iterator is of the same type and we can downcast.
      GTEST_CHECK_(BaseGenerator() == other.BaseGenerator())
          << "The program attempted to compare iterators "
          << "from different generators." << std::endl;
      const int other_index =
          CheckedDowncastToActualType<const Iterator>(&other)->index_;
      return index_ == other_index;
    }

   private:
    Iterator(const Iterator& other)
        : base_(other.base_), value_(other.value_), index_(other.index_),
          step_(other.step_) {}

    const ParamGeneratorInterface<T>* const base_;
    T value_;
    int index_;
    const IncrementT step_;
  };  // class RangeGenerator::Iterator

  static int CalculateEndIndex(const T& begin,
                               const T& end,
                               const IncrementT& step) {
    int end_index = 0;
    for (T i = begin; i < end; i = i + step)
      end_index++;
    return end_index;
  }

  const T begin_;
  const T end_;
  const IncrementT step_;
  // The index for the end() iterator. All the elements in the generated
  // sequence are indexed (0-based) to aid iterator comparison.
  const int end_index_;
};  // class RangeGenerator


// Generates values from a pair of STL-style iterators. Used in the
// ValuesIn() function. The elements are copied from the source range
// since the source can be located on the stack, and the generator
// is likely to persist beyond that stack frame.
template <typename T>
class ValuesInIteratorRangeGenerator : public ParamGeneratorInterface<T> {
 public:
  template <typename ForwardIterator>
  ValuesInIteratorRangeGenerator(ForwardIterator begin, ForwardIterator end)
      : container_(begin, end) {}
  virtual ~ValuesInIteratorRangeGenerator() {}

  virtual ParamIteratorInterface<T>* Begin() const {
    return new Iterator(this, container_.begin());
  }
  virtual ParamIteratorInterface<T>* End() const {
    return new Iterator(this, container_.end());
  }

 private:
  typedef typename ::std::vector<T> ContainerType;

  class Iterator : public ParamIteratorInterface<T> {
   public:
    Iterator(const ParamGeneratorInterface<T>* base,
             typename ContainerType::const_iterator iterator)
        :  base_(base), iterator_(iterator) {}
    virtual ~Iterator() {}

    virtual const ParamGeneratorInterface<T>* BaseGenerator() const {
      return base_;
    }
    virtual void Advance() {
      ++iterator_;
      value_.reset();
    }
    virtual ParamIteratorInterface<T>* Clone() const {
      return new Iterator(*this);
    }
    // We need to use cached value referenced by iterator_ because *iterator_
    // can return a temporary object (and of type other then T), so just