diff --git a/include/gmock/gmock-generated-matchers.h b/include/gmock/gmock-generated-matchers.h
index 2790e06c..2cc5746e 100644
--- a/include/gmock/gmock-generated-matchers.h
+++ b/include/gmock/gmock-generated-matchers.h
@@ -946,25 +946,29 @@ ElementsAreArray(const T (&array)[N]) {
 // Describing Parameterized Matchers
 // =================================
 //
-// When defining a parameterized matcher, you can use Python-style
-// interpolations in the description string to refer to the parameter
-// values.  We support the following syntax currently:
+// The last argument to MATCHER*() is a string-typed expression.  The
+// expression can reference all of the matcher's parameters and a
+// special bool-typed variable named 'negation'.  When 'negation' is
+// false, the expression should evaluate to the matcher's description;
+// otherwise it should evaluate to the description of the negation of
+// the matcher.  For example,
 //
-//   %%       a single '%' character
-//   %(*)s    all parameters of the matcher printed as a tuple
-//   %(foo)s  value of the matcher parameter named 'foo'
+//   using testing::PrintToString;
 //
-// For example,
-//
-//   MATCHER_P2(InClosedRange, low, hi, "is in range [%(low)s, %(hi)s]") {
+//   MATCHER_P2(InClosedRange, low, hi,
+//       string(negation ? "is not" : "is") + " in range [" +
+//       PrintToString(low) + ", " + PrintToString(hi) + "]") {
 //     return low <= arg && arg <= hi;
 //   }
 //   ...
 //   EXPECT_THAT(3, InClosedRange(4, 6));
+//   EXPECT_THAT(3, Not(InClosedRange(2, 4)));
 //
-// would generate a failure that contains the message:
+// would generate two failures that contain the text:
 //
 //   Expected: is in range [4, 6]
+//   ...
+//   Expected: is not in range [2, 4]
 //
 // If you specify "" as the description, the failure message will
 // contain the sequence of words in the matcher name followed by the
@@ -973,10 +977,13 @@ ElementsAreArray(const T (&array)[N]) {
 //   MATCHER_P2(InClosedRange, low, hi, "") { ... }
 //   ...
 //   EXPECT_THAT(3, InClosedRange(4, 6));
+//   EXPECT_THAT(3, Not(InClosedRange(2, 4)));
 //
-// would generate a failure that contains the text:
+// would generate two failures that contain the text:
 //
 //   Expected: in closed range (4, 6)
+//   ...
+//   Expected: not (in closed range (2, 4))
 //
 // Types of Matcher Parameters
 // ===========================
@@ -1065,33 +1072,36 @@ ElementsAreArray(const T (&array)[N]) {
     template <typename arg_type>\
     class gmock_Impl : public ::testing::MatcherInterface<arg_type> {\
      public:\
-      gmock_Impl(const ::testing::internal::Interpolations& gmock_interp)\
-           : gmock_interp_(gmock_interp) {}\
+      gmock_Impl()\
+           {}\
       virtual bool MatchAndExplain(\
           arg_type arg, ::testing::MatchResultListener* result_listener) const;\
       virtual void DescribeTo(::std::ostream* gmock_os) const {\
-        const ::testing::internal::Strings& gmock_printed_params = \
-            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
-                ::std::tr1::tuple<>());\
-        *gmock_os << ::testing::internal::FormatMatcherDescription(\
-                     #name, description, gmock_interp_, gmock_printed_params);\
+        *gmock_os << FormatDescription(false);\
+      }\
+      virtual void DescribeNegationTo(::std::ostream* gmock_os) const {\
+        *gmock_os << FormatDescription(true);\
       }\
-      const ::testing::internal::Interpolations gmock_interp_;\
      private:\
+      ::testing::internal::string FormatDescription(bool negation) const {\
+        const ::testing::internal::string gmock_description = (description);\
+        if (!gmock_description.empty())\
+          return gmock_description;\
+        return ::testing::internal::FormatMatcherDescription(\
+            negation, #name,\
+            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
+                ::std::tr1::tuple<>()));\
+      }\
       GTEST_DISALLOW_ASSIGN_(gmock_Impl);\
     };\
     template <typename arg_type>\
     operator ::testing::Matcher<arg_type>() const {\
       return ::testing::Matcher<arg_type>(\
-          new gmock_Impl<arg_type>(gmock_interp_));\
+          new gmock_Impl<arg_type>());\
     }\
     name##Matcher() {\
-      const char* gmock_param_names[] = { NULL };\
-      gmock_interp_ = ::testing::internal::ValidateMatcherDescription(\
-          gmock_param_names, ("" description ""));\
     }\
    private:\
-    ::testing::internal::Interpolations gmock_interp_;\
     GTEST_DISALLOW_ASSIGN_(name##Matcher);\
   };\
   inline name##Matcher name() {\
@@ -1110,36 +1120,38 @@ ElementsAreArray(const T (&array)[N]) {
     template <typename arg_type>\
     class gmock_Impl : public ::testing::MatcherInterface<arg_type> {\
      public:\
-      explicit gmock_Impl(p0##_type gmock_p0, \
-          const ::testing::internal::Interpolations& gmock_interp)\
-           : p0(gmock_p0), gmock_interp_(gmock_interp) {}\
+      explicit gmock_Impl(p0##_type gmock_p0)\
+           : p0(gmock_p0) {}\
       virtual bool MatchAndExplain(\
           arg_type arg, ::testing::MatchResultListener* result_listener) const;\
       virtual void DescribeTo(::std::ostream* gmock_os) const {\
-        const ::testing::internal::Strings& gmock_printed_params = \
-            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
-                ::std::tr1::tuple<p0##_type>(p0));\
-        *gmock_os << ::testing::internal::FormatMatcherDescription(\
-                     #name, description, gmock_interp_, gmock_printed_params);\
+        *gmock_os << FormatDescription(false);\
+      }\
+      virtual void DescribeNegationTo(::std::ostream* gmock_os) const {\
+        *gmock_os << FormatDescription(true);\
       }\
       p0##_type p0;\
-      const ::testing::internal::Interpolations gmock_interp_;\
      private:\
+      ::testing::internal::string FormatDescription(bool negation) const {\
+        const ::testing::internal::string gmock_description = (description);\
+        if (!gmock_description.empty())\
+          return gmock_description;\
+        return ::testing::internal::FormatMatcherDescription(\
+            negation, #name,\
+            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
+                ::std::tr1::tuple<p0##_type>(p0)));\
+      }\
       GTEST_DISALLOW_ASSIGN_(gmock_Impl);\
     };\
     template <typename arg_type>\
     operator ::testing::Matcher<arg_type>() const {\
       return ::testing::Matcher<arg_type>(\
-          new gmock_Impl<arg_type>(p0, gmock_interp_));\
+          new gmock_Impl<arg_type>(p0));\
     }\
     name##MatcherP(p0##_type gmock_p0) : p0(gmock_p0) {\
-      const char* gmock_param_names[] = { #p0, NULL };\
-      gmock_interp_ = ::testing::internal::ValidateMatcherDescription(\
-          gmock_param_names, ("" description ""));\
     }\
     p0##_type p0;\
    private:\
-    ::testing::internal::Interpolations gmock_interp_;\
     GTEST_DISALLOW_ASSIGN_(name##MatcherP);\
   };\
   template <typename p0##_type>\
@@ -1160,39 +1172,41 @@ ElementsAreArray(const T (&array)[N]) {
     template <typename arg_type>\
     class gmock_Impl : public ::testing::MatcherInterface<arg_type> {\
      public:\
-      gmock_Impl(p0##_type gmock_p0, p1##_type gmock_p1, \
-          const ::testing::internal::Interpolations& gmock_interp)\
-           : p0(gmock_p0), p1(gmock_p1), gmock_interp_(gmock_interp) {}\
+      gmock_Impl(p0##_type gmock_p0, p1##_type gmock_p1)\
+           : p0(gmock_p0), p1(gmock_p1) {}\
       virtual bool MatchAndExplain(\
           arg_type arg, ::testing::MatchResultListener* result_listener) const;\
       virtual void DescribeTo(::std::ostream* gmock_os) const {\
-        const ::testing::internal::Strings& gmock_printed_params = \
-            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
-                ::std::tr1::tuple<p0##_type, p1##_type>(p0, p1));\
-        *gmock_os << ::testing::internal::FormatMatcherDescription(\
-                     #name, description, gmock_interp_, gmock_printed_params);\
+        *gmock_os << FormatDescription(false);\
+      }\
+      virtual void DescribeNegationTo(::std::ostream* gmock_os) const {\
+        *gmock_os << FormatDescription(true);\
       }\
       p0##_type p0;\
       p1##_type p1;\
-      const ::testing::internal::Interpolations gmock_interp_;\
      private:\
+      ::testing::internal::string FormatDescription(bool negation) const {\
+        const ::testing::internal::string gmock_description = (description);\
+        if (!gmock_description.empty())\
+          return gmock_description;\
+        return ::testing::internal::FormatMatcherDescription(\
+            negation, #name,\
+            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
+                ::std::tr1::tuple<p0##_type, p1##_type>(p0, p1)));\
+      }\
       GTEST_DISALLOW_ASSIGN_(gmock_Impl);\
     };\
     template <typename arg_type>\
     operator ::testing::Matcher<arg_type>() const {\
       return ::testing::Matcher<arg_type>(\
-          new gmock_Impl<arg_type>(p0, p1, gmock_interp_));\
+          new gmock_Impl<arg_type>(p0, p1));\
     }\
     name##MatcherP2(p0##_type gmock_p0, p1##_type gmock_p1) : p0(gmock_p0), \
         p1(gmock_p1) {\
-      const char* gmock_param_names[] = { #p0, #p1, NULL };\
-      gmock_interp_ = ::testing::internal::ValidateMatcherDescription(\
-          gmock_param_names, ("" description ""));\
     }\
     p0##_type p0;\
     p1##_type p1;\
    private:\
-    ::testing::internal::Interpolations gmock_interp_;\
     GTEST_DISALLOW_ASSIGN_(name##MatcherP2);\
   };\
   template <typename p0##_type, typename p1##_type>\
@@ -1215,43 +1229,44 @@ ElementsAreArray(const T (&array)[N]) {
     template <typename arg_type>\
     class gmock_Impl : public ::testing::MatcherInterface<arg_type> {\
      public:\
-      gmock_Impl(p0##_type gmock_p0, p1##_type gmock_p1, p2##_type gmock_p2, \
-          const ::testing::internal::Interpolations& gmock_interp)\
-           : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2), \
-               gmock_interp_(gmock_interp) {}\
+      gmock_Impl(p0##_type gmock_p0, p1##_type gmock_p1, p2##_type gmock_p2)\
+           : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2) {}\
       virtual bool MatchAndExplain(\
           arg_type arg, ::testing::MatchResultListener* result_listener) const;\
       virtual void DescribeTo(::std::ostream* gmock_os) const {\
-        const ::testing::internal::Strings& gmock_printed_params = \
-            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
-                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type>(p0, p1, \
-                    p2));\
-        *gmock_os << ::testing::internal::FormatMatcherDescription(\
-                     #name, description, gmock_interp_, gmock_printed_params);\
+        *gmock_os << FormatDescription(false);\
+      }\
+      virtual void DescribeNegationTo(::std::ostream* gmock_os) const {\
+        *gmock_os << FormatDescription(true);\
       }\
       p0##_type p0;\
       p1##_type p1;\
       p2##_type p2;\
-      const ::testing::internal::Interpolations gmock_interp_;\
      private:\
+      ::testing::internal::string FormatDescription(bool negation) const {\
+        const ::testing::internal::string gmock_description = (description);\
+        if (!gmock_description.empty())\
+          return gmock_description;\
+        return ::testing::internal::FormatMatcherDescription(\
+            negation, #name,\
+            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
+                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type>(p0, p1, \
+                    p2)));\
+      }\
       GTEST_DISALLOW_ASSIGN_(gmock_Impl);\
     };\
     template <typename arg_type>\
     operator ::testing::Matcher<arg_type>() const {\
       return ::testing::Matcher<arg_type>(\
-          new gmock_Impl<arg_type>(p0, p1, p2, gmock_interp_));\
+          new gmock_Impl<arg_type>(p0, p1, p2));\
     }\
     name##MatcherP3(p0##_type gmock_p0, p1##_type gmock_p1, \
         p2##_type gmock_p2) : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2) {\
-      const char* gmock_param_names[] = { #p0, #p1, #p2, NULL };\
-      gmock_interp_ = ::testing::internal::ValidateMatcherDescription(\
-          gmock_param_names, ("" description ""));\
     }\
     p0##_type p0;\
     p1##_type p1;\
     p2##_type p2;\
    private:\
-    ::testing::internal::Interpolations gmock_interp_;\
     GTEST_DISALLOW_ASSIGN_(name##MatcherP3);\
   };\
   template <typename p0##_type, typename p1##_type, typename p2##_type>\
@@ -1276,46 +1291,47 @@ ElementsAreArray(const T (&array)[N]) {
     class gmock_Impl : public ::testing::MatcherInterface<arg_type> {\
      public:\
       gmock_Impl(p0##_type gmock_p0, p1##_type gmock_p1, p2##_type gmock_p2, \
-          p3##_type gmock_p3, \
-          const ::testing::internal::Interpolations& gmock_interp)\
-           : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2), p3(gmock_p3), \
-               gmock_interp_(gmock_interp) {}\
+          p3##_type gmock_p3)\
+           : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2), p3(gmock_p3) {}\
       virtual bool MatchAndExplain(\
           arg_type arg, ::testing::MatchResultListener* result_listener) const;\
       virtual void DescribeTo(::std::ostream* gmock_os) const {\
-        const ::testing::internal::Strings& gmock_printed_params = \
-            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
-                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, \
-                    p3##_type>(p0, p1, p2, p3));\
-        *gmock_os << ::testing::internal::FormatMatcherDescription(\
-                     #name, description, gmock_interp_, gmock_printed_params);\
+        *gmock_os << FormatDescription(false);\
+      }\
+      virtual void DescribeNegationTo(::std::ostream* gmock_os) const {\
+        *gmock_os << FormatDescription(true);\
       }\
       p0##_type p0;\
       p1##_type p1;\
       p2##_type p2;\
       p3##_type p3;\
-      const ::testing::internal::Interpolations gmock_interp_;\
      private:\
+      ::testing::internal::string FormatDescription(bool negation) const {\
+        const ::testing::internal::string gmock_description = (description);\
+        if (!gmock_description.empty())\
+          return gmock_description;\
+        return ::testing::internal::FormatMatcherDescription(\
+            negation, #name,\
+            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
+                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, \
+                    p3##_type>(p0, p1, p2, p3)));\
+      }\
       GTEST_DISALLOW_ASSIGN_(gmock_Impl);\
     };\
     template <typename arg_type>\
     operator ::testing::Matcher<arg_type>() const {\
       return ::testing::Matcher<arg_type>(\
-          new gmock_Impl<arg_type>(p0, p1, p2, p3, gmock_interp_));\
+          new gmock_Impl<arg_type>(p0, p1, p2, p3));\
     }\
     name##MatcherP4(p0##_type gmock_p0, p1##_type gmock_p1, \
         p2##_type gmock_p2, p3##_type gmock_p3) : p0(gmock_p0), p1(gmock_p1), \
         p2(gmock_p2), p3(gmock_p3) {\
-      const char* gmock_param_names[] = { #p0, #p1, #p2, #p3, NULL };\
-      gmock_interp_ = ::testing::internal::ValidateMatcherDescription(\
-          gmock_param_names, ("" description ""));\
     }\
     p0##_type p0;\
     p1##_type p1;\
     p2##_type p2;\
     p3##_type p3;\
    private:\
-    ::testing::internal::Interpolations gmock_interp_;\
     GTEST_DISALLOW_ASSIGN_(name##MatcherP4);\
   };\
   template <typename p0##_type, typename p1##_type, typename p2##_type, \
@@ -1344,41 +1360,44 @@ ElementsAreArray(const T (&array)[N]) {
     class gmock_Impl : public ::testing::MatcherInterface<arg_type> {\
      public:\
       gmock_Impl(p0##_type gmock_p0, p1##_type gmock_p1, p2##_type gmock_p2, \
-          p3##_type gmock_p3, p4##_type gmock_p4, \
-          const ::testing::internal::Interpolations& gmock_interp)\
+          p3##_type gmock_p3, p4##_type gmock_p4)\
            : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2), p3(gmock_p3), \
-               p4(gmock_p4), gmock_interp_(gmock_interp) {}\
+               p4(gmock_p4) {}\
       virtual bool MatchAndExplain(\
           arg_type arg, ::testing::MatchResultListener* result_listener) const;\
       virtual void DescribeTo(::std::ostream* gmock_os) const {\
-        const ::testing::internal::Strings& gmock_printed_params = \
-            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
-                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, p3##_type, \
-                    p4##_type>(p0, p1, p2, p3, p4));\
-        *gmock_os << ::testing::internal::FormatMatcherDescription(\
-                     #name, description, gmock_interp_, gmock_printed_params);\
+        *gmock_os << FormatDescription(false);\
+      }\
+      virtual void DescribeNegationTo(::std::ostream* gmock_os) const {\
+        *gmock_os << FormatDescription(true);\
       }\
       p0##_type p0;\
       p1##_type p1;\
       p2##_type p2;\
       p3##_type p3;\
       p4##_type p4;\
-      const ::testing::internal::Interpolations gmock_interp_;\
      private:\
+      ::testing::internal::string FormatDescription(bool negation) const {\
+        const ::testing::internal::string gmock_description = (description);\
+        if (!gmock_description.empty())\
+          return gmock_description;\
+        return ::testing::internal::FormatMatcherDescription(\
+            negation, #name,\
+            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
+                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, p3##_type, \
+                    p4##_type>(p0, p1, p2, p3, p4)));\
+      }\
       GTEST_DISALLOW_ASSIGN_(gmock_Impl);\
     };\
     template <typename arg_type>\
     operator ::testing::Matcher<arg_type>() const {\
       return ::testing::Matcher<arg_type>(\
-          new gmock_Impl<arg_type>(p0, p1, p2, p3, p4, gmock_interp_));\
+          new gmock_Impl<arg_type>(p0, p1, p2, p3, p4));\
     }\
     name##MatcherP5(p0##_type gmock_p0, p1##_type gmock_p1, \
         p2##_type gmock_p2, p3##_type gmock_p3, \
         p4##_type gmock_p4) : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2), \
         p3(gmock_p3), p4(gmock_p4) {\
-      const char* gmock_param_names[] = { #p0, #p1, #p2, #p3, #p4, NULL };\
-      gmock_interp_ = ::testing::internal::ValidateMatcherDescription(\
-          gmock_param_names, ("" description ""));\
     }\
     p0##_type p0;\
     p1##_type p1;\
@@ -1386,7 +1405,6 @@ ElementsAreArray(const T (&array)[N]) {
     p3##_type p3;\
     p4##_type p4;\
    private:\
-    ::testing::internal::Interpolations gmock_interp_;\
     GTEST_DISALLOW_ASSIGN_(name##MatcherP5);\
   };\
   template <typename p0##_type, typename p1##_type, typename p2##_type, \
@@ -1415,19 +1433,16 @@ ElementsAreArray(const T (&array)[N]) {
     class gmock_Impl : public ::testing::MatcherInterface<arg_type> {\
      public:\
       gmock_Impl(p0##_type gmock_p0, p1##_type gmock_p1, p2##_type gmock_p2, \
-          p3##_type gmock_p3, p4##_type gmock_p4, p5##_type gmock_p5, \
-          const ::testing::internal::Interpolations& gmock_interp)\
+          p3##_type gmock_p3, p4##_type gmock_p4, p5##_type gmock_p5)\
            : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2), p3(gmock_p3), \
-               p4(gmock_p4), p5(gmock_p5), gmock_interp_(gmock_interp) {}\
+               p4(gmock_p4), p5(gmock_p5) {}\
       virtual bool MatchAndExplain(\
           arg_type arg, ::testing::MatchResultListener* result_listener) const;\
       virtual void DescribeTo(::std::ostream* gmock_os) const {\
-        const ::testing::internal::Strings& gmock_printed_params = \
-            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
-                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, p3##_type, \
-                    p4##_type, p5##_type>(p0, p1, p2, p3, p4, p5));\
-        *gmock_os << ::testing::internal::FormatMatcherDescription(\
-                     #name, description, gmock_interp_, gmock_printed_params);\
+        *gmock_os << FormatDescription(false);\
+      }\
+      virtual void DescribeNegationTo(::std::ostream* gmock_os) const {\
+        *gmock_os << FormatDescription(true);\
       }\
       p0##_type p0;\
       p1##_type p1;\
@@ -1435,22 +1450,28 @@ ElementsAreArray(const T (&array)[N]) {
       p3##_type p3;\
       p4##_type p4;\
       p5##_type p5;\
-      const ::testing::internal::Interpolations gmock_interp_;\
      private:\
+      ::testing::internal::string FormatDescription(bool negation) const {\
+        const ::testing::internal::string gmock_description = (description);\
+        if (!gmock_description.empty())\
+          return gmock_description;\
+        return ::testing::internal::FormatMatcherDescription(\
+            negation, #name,\
+            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
+                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, p3##_type, \
+                    p4##_type, p5##_type>(p0, p1, p2, p3, p4, p5)));\
+      }\
       GTEST_DISALLOW_ASSIGN_(gmock_Impl);\
     };\
     template <typename arg_type>\
     operator ::testing::Matcher<arg_type>() const {\
       return ::testing::Matcher<arg_type>(\
-          new gmock_Impl<arg_type>(p0, p1, p2, p3, p4, p5, gmock_interp_));\
+          new gmock_Impl<arg_type>(p0, p1, p2, p3, p4, p5));\
     }\
     name##MatcherP6(p0##_type gmock_p0, p1##_type gmock_p1, \
         p2##_type gmock_p2, p3##_type gmock_p3, p4##_type gmock_p4, \
         p5##_type gmock_p5) : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2), \
         p3(gmock_p3), p4(gmock_p4), p5(gmock_p5) {\
-      const char* gmock_param_names[] = { #p0, #p1, #p2, #p3, #p4, #p5, NULL };\
-      gmock_interp_ = ::testing::internal::ValidateMatcherDescription(\
-          gmock_param_names, ("" description ""));\
     }\
     p0##_type p0;\
     p1##_type p1;\
@@ -1459,7 +1480,6 @@ ElementsAreArray(const T (&array)[N]) {
     p4##_type p4;\
     p5##_type p5;\
    private:\
-    ::testing::internal::Interpolations gmock_interp_;\
     GTEST_DISALLOW_ASSIGN_(name##MatcherP6);\
   };\
   template <typename p0##_type, typename p1##_type, typename p2##_type, \
@@ -1490,21 +1510,16 @@ ElementsAreArray(const T (&array)[N]) {
      public:\
       gmock_Impl(p0##_type gmock_p0, p1##_type gmock_p1, p2##_type gmock_p2, \
           p3##_type gmock_p3, p4##_type gmock_p4, p5##_type gmock_p5, \
-          p6##_type gmock_p6, \
-          const ::testing::internal::Interpolations& gmock_interp)\
+          p6##_type gmock_p6)\
            : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2), p3(gmock_p3), \
-               p4(gmock_p4), p5(gmock_p5), p6(gmock_p6), \
-               gmock_interp_(gmock_interp) {}\
+               p4(gmock_p4), p5(gmock_p5), p6(gmock_p6) {}\
       virtual bool MatchAndExplain(\
           arg_type arg, ::testing::MatchResultListener* result_listener) const;\
       virtual void DescribeTo(::std::ostream* gmock_os) const {\
-        const ::testing::internal::Strings& gmock_printed_params = \
-            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
-                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, p3##_type, \
-                    p4##_type, p5##_type, p6##_type>(p0, p1, p2, p3, p4, p5, \
-                    p6));\
-        *gmock_os << ::testing::internal::FormatMatcherDescription(\
-                     #name, description, gmock_interp_, gmock_printed_params);\
+        *gmock_os << FormatDescription(false);\
+      }\
+      virtual void DescribeNegationTo(::std::ostream* gmock_os) const {\
+        *gmock_os << FormatDescription(true);\
       }\
       p0##_type p0;\
       p1##_type p1;\
@@ -1513,24 +1528,30 @@ ElementsAreArray(const T (&array)[N]) {
       p4##_type p4;\
       p5##_type p5;\
       p6##_type p6;\
-      const ::testing::internal::Interpolations gmock_interp_;\
      private:\
+      ::testing::internal::string FormatDescription(bool negation) const {\
+        const ::testing::internal::string gmock_description = (description);\
+        if (!gmock_description.empty())\
+          return gmock_description;\
+        return ::testing::internal::FormatMatcherDescription(\
+            negation, #name,\
+            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
+                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, p3##_type, \
+                    p4##_type, p5##_type, p6##_type>(p0, p1, p2, p3, p4, p5, \
+                    p6)));\
+      }\
       GTEST_DISALLOW_ASSIGN_(gmock_Impl);\
     };\
     template <typename arg_type>\
     operator ::testing::Matcher<arg_type>() const {\
       return ::testing::Matcher<arg_type>(\
-          new gmock_Impl<arg_type>(p0, p1, p2, p3, p4, p5, p6, gmock_interp_));\
+          new gmock_Impl<arg_type>(p0, p1, p2, p3, p4, p5, p6));\
     }\
     name##MatcherP7(p0##_type gmock_p0, p1##_type gmock_p1, \
         p2##_type gmock_p2, p3##_type gmock_p3, p4##_type gmock_p4, \
         p5##_type gmock_p5, p6##_type gmock_p6) : p0(gmock_p0), p1(gmock_p1), \
         p2(gmock_p2), p3(gmock_p3), p4(gmock_p4), p5(gmock_p5), \
         p6(gmock_p6) {\
-      const char* gmock_param_names[] = { #p0, #p1, #p2, #p3, #p4, #p5, #p6, \
-          NULL };\
-      gmock_interp_ = ::testing::internal::ValidateMatcherDescription(\
-          gmock_param_names, ("" description ""));\
     }\
     p0##_type p0;\
     p1##_type p1;\
@@ -1540,7 +1561,6 @@ ElementsAreArray(const T (&array)[N]) {
     p5##_type p5;\
     p6##_type p6;\
    private:\
-    ::testing::internal::Interpolations gmock_interp_;\
     GTEST_DISALLOW_ASSIGN_(name##MatcherP7);\
   };\
   template <typename p0##_type, typename p1##_type, typename p2##_type, \
@@ -1574,21 +1594,16 @@ ElementsAreArray(const T (&array)[N]) {
      public:\
       gmock_Impl(p0##_type gmock_p0, p1##_type gmock_p1, p2##_type gmock_p2, \
           p3##_type gmock_p3, p4##_type gmock_p4, p5##_type gmock_p5, \
-          p6##_type gmock_p6, p7##_type gmock_p7, \
-          const ::testing::internal::Interpolations& gmock_interp)\
+          p6##_type gmock_p6, p7##_type gmock_p7)\
            : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2), p3(gmock_p3), \
-               p4(gmock_p4), p5(gmock_p5), p6(gmock_p6), p7(gmock_p7), \
-               gmock_interp_(gmock_interp) {}\
+               p4(gmock_p4), p5(gmock_p5), p6(gmock_p6), p7(gmock_p7) {}\
       virtual bool MatchAndExplain(\
           arg_type arg, ::testing::MatchResultListener* result_listener) const;\
       virtual void DescribeTo(::std::ostream* gmock_os) const {\
-        const ::testing::internal::Strings& gmock_printed_params = \
-            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
-                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, p3##_type, \
-                    p4##_type, p5##_type, p6##_type, p7##_type>(p0, p1, p2, \
-                    p3, p4, p5, p6, p7));\
-        *gmock_os << ::testing::internal::FormatMatcherDescription(\
-                     #name, description, gmock_interp_, gmock_printed_params);\
+        *gmock_os << FormatDescription(false);\
+      }\
+      virtual void DescribeNegationTo(::std::ostream* gmock_os) const {\
+        *gmock_os << FormatDescription(true);\
       }\
       p0##_type p0;\
       p1##_type p1;\
@@ -1598,15 +1613,24 @@ ElementsAreArray(const T (&array)[N]) {
       p5##_type p5;\
       p6##_type p6;\
       p7##_type p7;\
-      const ::testing::internal::Interpolations gmock_interp_;\
      private:\
+      ::testing::internal::string FormatDescription(bool negation) const {\
+        const ::testing::internal::string gmock_description = (description);\
+        if (!gmock_description.empty())\
+          return gmock_description;\
+        return ::testing::internal::FormatMatcherDescription(\
+            negation, #name,\
+            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
+                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, p3##_type, \
+                    p4##_type, p5##_type, p6##_type, p7##_type>(p0, p1, p2, \
+                    p3, p4, p5, p6, p7)));\
+      }\
       GTEST_DISALLOW_ASSIGN_(gmock_Impl);\
     };\
     template <typename arg_type>\
     operator ::testing::Matcher<arg_type>() const {\
       return ::testing::Matcher<arg_type>(\
-          new gmock_Impl<arg_type>(p0, p1, p2, p3, p4, p5, p6, p7, \
-              gmock_interp_));\
+          new gmock_Impl<arg_type>(p0, p1, p2, p3, p4, p5, p6, p7));\
     }\
     name##MatcherP8(p0##_type gmock_p0, p1##_type gmock_p1, \
         p2##_type gmock_p2, p3##_type gmock_p3, p4##_type gmock_p4, \
@@ -1614,10 +1638,6 @@ ElementsAreArray(const T (&array)[N]) {
         p7##_type gmock_p7) : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2), \
         p3(gmock_p3), p4(gmock_p4), p5(gmock_p5), p6(gmock_p6), \
         p7(gmock_p7) {\
-      const char* gmock_param_names[] = { #p0, #p1, #p2, #p3, #p4, #p5, #p6, \
-          #p7, NULL };\
-      gmock_interp_ = ::testing::internal::ValidateMatcherDescription(\
-          gmock_param_names, ("" description ""));\
     }\
     p0##_type p0;\
     p1##_type p1;\
@@ -1628,7 +1648,6 @@ ElementsAreArray(const T (&array)[N]) {
     p6##_type p6;\
     p7##_type p7;\
    private:\
-    ::testing::internal::Interpolations gmock_interp_;\
     GTEST_DISALLOW_ASSIGN_(name##MatcherP8);\
   };\
   template <typename p0##_type, typename p1##_type, typename p2##_type, \
@@ -1664,21 +1683,17 @@ ElementsAreArray(const T (&array)[N]) {
      public:\
       gmock_Impl(p0##_type gmock_p0, p1##_type gmock_p1, p2##_type gmock_p2, \
           p3##_type gmock_p3, p4##_type gmock_p4, p5##_type gmock_p5, \
-          p6##_type gmock_p6, p7##_type gmock_p7, p8##_type gmock_p8, \
-          const ::testing::internal::Interpolations& gmock_interp)\
+          p6##_type gmock_p6, p7##_type gmock_p7, p8##_type gmock_p8)\
            : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2), p3(gmock_p3), \
                p4(gmock_p4), p5(gmock_p5), p6(gmock_p6), p7(gmock_p7), \
-               p8(gmock_p8), gmock_interp_(gmock_interp) {}\
+               p8(gmock_p8) {}\
       virtual bool MatchAndExplain(\
           arg_type arg, ::testing::MatchResultListener* result_listener) const;\
       virtual void DescribeTo(::std::ostream* gmock_os) const {\
-        const ::testing::internal::Strings& gmock_printed_params = \
-            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
-                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, p3##_type, \
-                    p4##_type, p5##_type, p6##_type, p7##_type, \
-                    p8##_type>(p0, p1, p2, p3, p4, p5, p6, p7, p8));\
-        *gmock_os << ::testing::internal::FormatMatcherDescription(\
-                     #name, description, gmock_interp_, gmock_printed_params);\
+        *gmock_os << FormatDescription(false);\
+      }\
+      virtual void DescribeNegationTo(::std::ostream* gmock_os) const {\
+        *gmock_os << FormatDescription(true);\
       }\
       p0##_type p0;\
       p1##_type p1;\
@@ -1689,15 +1704,24 @@ ElementsAreArray(const T (&array)[N]) {
       p6##_type p6;\
       p7##_type p7;\
       p8##_type p8;\
-      const ::testing::internal::Interpolations gmock_interp_;\
      private:\
+      ::testing::internal::string FormatDescription(bool negation) const {\
+        const ::testing::internal::string gmock_description = (description);\
+        if (!gmock_description.empty())\
+          return gmock_description;\
+        return ::testing::internal::FormatMatcherDescription(\
+            negation, #name,\
+            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
+                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, p3##_type, \
+                    p4##_type, p5##_type, p6##_type, p7##_type, \
+                    p8##_type>(p0, p1, p2, p3, p4, p5, p6, p7, p8)));\
+      }\
       GTEST_DISALLOW_ASSIGN_(gmock_Impl);\
     };\
     template <typename arg_type>\
     operator ::testing::Matcher<arg_type>() const {\
       return ::testing::Matcher<arg_type>(\
-          new gmock_Impl<arg_type>(p0, p1, p2, p3, p4, p5, p6, p7, p8, \
-              gmock_interp_));\
+          new gmock_Impl<arg_type>(p0, p1, p2, p3, p4, p5, p6, p7, p8));\
     }\
     name##MatcherP9(p0##_type gmock_p0, p1##_type gmock_p1, \
         p2##_type gmock_p2, p3##_type gmock_p3, p4##_type gmock_p4, \
@@ -1705,10 +1729,6 @@ ElementsAreArray(const T (&array)[N]) {
         p8##_type gmock_p8) : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2), \
         p3(gmock_p3), p4(gmock_p4), p5(gmock_p5), p6(gmock_p6), p7(gmock_p7), \
         p8(gmock_p8) {\
-      const char* gmock_param_names[] = { #p0, #p1, #p2, #p3, #p4, #p5, #p6, \
-          #p7, #p8, NULL };\
-      gmock_interp_ = ::testing::internal::ValidateMatcherDescription(\
-          gmock_param_names, ("" description ""));\
     }\
     p0##_type p0;\
     p1##_type p1;\
@@ -1720,7 +1740,6 @@ ElementsAreArray(const T (&array)[N]) {
     p7##_type p7;\
     p8##_type p8;\
    private:\
-    ::testing::internal::Interpolations gmock_interp_;\
     GTEST_DISALLOW_ASSIGN_(name##MatcherP9);\
   };\
   template <typename p0##_type, typename p1##_type, typename p2##_type, \
@@ -1759,21 +1778,17 @@ ElementsAreArray(const T (&array)[N]) {
       gmock_Impl(p0##_type gmock_p0, p1##_type gmock_p1, p2##_type gmock_p2, \
           p3##_type gmock_p3, p4##_type gmock_p4, p5##_type gmock_p5, \
           p6##_type gmock_p6, p7##_type gmock_p7, p8##_type gmock_p8, \
-          p9##_type gmock_p9, \
-          const ::testing::internal::Interpolations& gmock_interp)\
+          p9##_type gmock_p9)\
            : p0(gmock_p0), p1(gmock_p1), p2(gmock_p2), p3(gmock_p3), \
                p4(gmock_p4), p5(gmock_p5), p6(gmock_p6), p7(gmock_p7), \
-               p8(gmock_p8), p9(gmock_p9), gmock_interp_(gmock_interp) {}\
+               p8(gmock_p8), p9(gmock_p9) {}\
       virtual bool MatchAndExplain(\
           arg_type arg, ::testing::MatchResultListener* result_listener) const;\
       virtual void DescribeTo(::std::ostream* gmock_os) const {\
-        const ::testing::internal::Strings& gmock_printed_params = \
-            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
-                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, p3##_type, \
-                    p4##_type, p5##_type, p6##_type, p7##_type, p8##_type, \
-                    p9##_type>(p0, p1, p2, p3, p4, p5, p6, p7, p8, p9));\
-        *gmock_os << ::testing::internal::FormatMatcherDescription(\
-                     #name, description, gmock_interp_, gmock_printed_params);\
+        *gmock_os << FormatDescription(false);\
+      }\
+      virtual void DescribeNegationTo(::std::ostream* gmock_os) const {\
+        *gmock_os << FormatDescription(true);\
       }\
       p0##_type p0;\
       p1##_type p1;\
@@ -1785,15 +1800,24 @@ ElementsAreArray(const T (&array)[N]) {
       p7##_type p7;\
       p8##_type p8;\
       p9##_type p9;\
-      const ::testing::internal::Interpolations gmock_interp_;\
      private:\
+      ::testing::internal::string FormatDescription(bool negation) const {\
+        const ::testing::internal::string gmock_description = (description);\
+        if (!gmock_description.empty())\
+          return gmock_description;\
+        return ::testing::internal::FormatMatcherDescription(\
+            negation, #name,\
+            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
+                ::std::tr1::tuple<p0##_type, p1##_type, p2##_type, p3##_type, \
+                    p4##_type, p5##_type, p6##_type, p7##_type, p8##_type, \
+                    p9##_type>(p0, p1, p2, p3, p4, p5, p6, p7, p8, p9)));\
+      }\
       GTEST_DISALLOW_ASSIGN_(gmock_Impl);\
     };\
     template <typename arg_type>\
     operator ::testing::Matcher<arg_type>() const {\
       return ::testing::Matcher<arg_type>(\
-          new gmock_Impl<arg_type>(p0, p1, p2, p3, p4, p5, p6, p7, p8, p9, \
-              gmock_interp_));\
+          new gmock_Impl<arg_type>(p0, p1, p2, p3, p4, p5, p6, p7, p8, p9));\
     }\
     name##MatcherP10(p0##_type gmock_p0, p1##_type gmock_p1, \
         p2##_type gmock_p2, p3##_type gmock_p3, p4##_type gmock_p4, \
@@ -1801,10 +1825,6 @@ ElementsAreArray(const T (&array)[N]) {
         p8##_type gmock_p8, p9##_type gmock_p9) : p0(gmock_p0), p1(gmock_p1), \
         p2(gmock_p2), p3(gmock_p3), p4(gmock_p4), p5(gmock_p5), p6(gmock_p6), \
         p7(gmock_p7), p8(gmock_p8), p9(gmock_p9) {\
-      const char* gmock_param_names[] = { #p0, #p1, #p2, #p3, #p4, #p5, #p6, \
-          #p7, #p8, #p9, NULL };\
-      gmock_interp_ = ::testing::internal::ValidateMatcherDescription(\
-          gmock_param_names, ("" description ""));\
     }\
     p0##_type p0;\
     p1##_type p1;\
@@ -1817,7 +1837,6 @@ ElementsAreArray(const T (&array)[N]) {
     p8##_type p8;\
     p9##_type p9;\
    private:\
-    ::testing::internal::Interpolations gmock_interp_;\
     GTEST_DISALLOW_ASSIGN_(name##MatcherP10);\
   };\
   template <typename p0##_type, typename p1##_type, typename p2##_type, \
diff --git a/include/gmock/gmock-generated-matchers.h.pump b/include/gmock/gmock-generated-matchers.h.pump
index db498ec0..9f19fb8b 100644
--- a/include/gmock/gmock-generated-matchers.h.pump
+++ b/include/gmock/gmock-generated-matchers.h.pump
@@ -402,25 +402,29 @@ $$   // show up in the generated code.
 // Describing Parameterized Matchers
 // =================================
 //
-// When defining a parameterized matcher, you can use Python-style
-// interpolations in the description string to refer to the parameter
-// values.  We support the following syntax currently:
+// The last argument to MATCHER*() is a string-typed expression.  The
+// expression can reference all of the matcher's parameters and a
+// special bool-typed variable named 'negation'.  When 'negation' is
+// false, the expression should evaluate to the matcher's description;
+// otherwise it should evaluate to the description of the negation of
+// the matcher.  For example,
 //
-//   %%       a single '%' character
-//   %(*)s    all parameters of the matcher printed as a tuple
-//   %(foo)s  value of the matcher parameter named 'foo'
+//   using testing::PrintToString;
 //
-// For example,
-//
-//   MATCHER_P2(InClosedRange, low, hi, "is in range [%(low)s, %(hi)s]") {
+//   MATCHER_P2(InClosedRange, low, hi,
+//       string(negation ? "is not" : "is") + " in range [" +
+//       PrintToString(low) + ", " + PrintToString(hi) + "]") {
 //     return low <= arg && arg <= hi;
 //   }
 //   ...
 //   EXPECT_THAT(3, InClosedRange(4, 6));
+//   EXPECT_THAT(3, Not(InClosedRange(2, 4)));
 //
-// would generate a failure that contains the message:
+// would generate two failures that contain the text:
 //
 //   Expected: is in range [4, 6]
+//   ...
+//   Expected: is not in range [2, 4]
 //
 // If you specify "" as the description, the failure message will
 // contain the sequence of words in the matcher name followed by the
@@ -429,10 +433,13 @@ $$   // show up in the generated code.
 //   MATCHER_P2(InClosedRange, low, hi, "") { ... }
 //   ...
 //   EXPECT_THAT(3, InClosedRange(4, 6));
+//   EXPECT_THAT(3, Not(InClosedRange(2, 4)));
 //
-// would generate a failure that contains the text:
+// would generate two failures that contain the text:
 //
 //   Expected: in closed range (4, 6)
+//   ...
+//   Expected: not (in closed range (2, 4))
 //
 // Types of Matcher Parameters
 // ===========================
@@ -529,11 +536,9 @@ $var template = [[$if i==0 [[]] $else [[
   template <$for j, [[typename p$j##_type]]>\
 ]]]]
 $var ctor_param_list = [[$for j, [[p$j##_type gmock_p$j]]]]
-$var impl_ctor_param_list = [[$for j [[p$j##_type gmock_p$j, ]]
-const ::testing::internal::Interpolations& gmock_interp]]
-$var impl_inits = [[ : $for j [[p$j(gmock_p$j), ]]gmock_interp_(gmock_interp)]]
+$var impl_ctor_param_list = [[$for j, [[p$j##_type gmock_p$j]]]]
+$var impl_inits = [[$if i==0 [[]] $else [[ : $for j, [[p$j(gmock_p$j)]]]]]]
 $var inits = [[$if i==0 [[]] $else [[ : $for j, [[p$j(gmock_p$j)]]]]]]
-$var params_and_interp = [[$for j [[p$j, ]]gmock_interp_]]
 $var params = [[$for j, [[p$j]]]]
 $var param_types = [[$if i==0 [[]] $else [[<$for j, [[p$j##_type]]>]]]]
 $var param_types_and_names = [[$for j, [[p$j##_type p$j]]]]
@@ -559,28 +564,31 @@ $var param_field_decls2 = [[$for j
       virtual bool MatchAndExplain(\
           arg_type arg, ::testing::MatchResultListener* result_listener) const;\
       virtual void DescribeTo(::std::ostream* gmock_os) const {\
-        const ::testing::internal::Strings& gmock_printed_params = \
-            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
-                ::std::tr1::tuple<$for j, [[p$j##_type]]>($for j, [[p$j]]));\
-        *gmock_os << ::testing::internal::FormatMatcherDescription(\
-                     #name, description, gmock_interp_, gmock_printed_params);\
+        *gmock_os << FormatDescription(false);\
+      }\
+      virtual void DescribeNegationTo(::std::ostream* gmock_os) const {\
+        *gmock_os << FormatDescription(true);\
       }\$param_field_decls
-      const ::testing::internal::Interpolations gmock_interp_;\
      private:\
+      ::testing::internal::string FormatDescription(bool negation) const {\
+        const ::testing::internal::string gmock_description = (description);\
+        if (!gmock_description.empty())\
+          return gmock_description;\
+        return ::testing::internal::FormatMatcherDescription(\
+            negation, #name,\
+            ::testing::internal::UniversalTersePrintTupleFieldsToStrings(\
+                ::std::tr1::tuple<$for j, [[p$j##_type]]>($for j, [[p$j]])));\
+      }\
       GTEST_DISALLOW_ASSIGN_(gmock_Impl);\
     };\
     template <typename arg_type>\
     operator ::testing::Matcher<arg_type>() const {\
       return ::testing::Matcher<arg_type>(\
-          new gmock_Impl<arg_type>($params_and_interp));\
+          new gmock_Impl<arg_type>($params));\
     }\
     $class_name($ctor_param_list)$inits {\
-      const char* gmock_param_names[] = { $for j [[#p$j, ]]NULL };\
-      gmock_interp_ = ::testing::internal::ValidateMatcherDescription(\
-          gmock_param_names, ("" description ""));\
     }\$param_field_decls2
    private:\
-    ::testing::internal::Interpolations gmock_interp_;\
     GTEST_DISALLOW_ASSIGN_($class_name);\
   };\$template
   inline $class_name$param_types name($param_types_and_names) {\
diff --git a/include/gmock/gmock-matchers.h b/include/gmock/gmock-matchers.h
index 2a42bf94..315e1f56 100644
--- a/include/gmock/gmock-matchers.h
+++ b/include/gmock/gmock-matchers.h
@@ -2527,41 +2527,13 @@ class ElementsAreArrayMatcher {
   GTEST_DISALLOW_ASSIGN_(ElementsAreArrayMatcher);
 };
 
-// Constants denoting interpolations in a matcher description string.
-const int kTupleInterpolation = -1;    // "%(*)s"
-const int kPercentInterpolation = -2;  // "%%"
-const int kInvalidInterpolation = -3;  // "%" followed by invalid text
-
-// Records the location and content of an interpolation.
-struct Interpolation {
-  Interpolation(const char* start, const char* end, int param)
-      : start_pos(start), end_pos(end), param_index(param) {}
-
-  // Points to the start of the interpolation (the '%' character).
-  const char* start_pos;
-  // Points to the first character after the interpolation.
-  const char* end_pos;
-  // 0-based index of the interpolated matcher parameter;
-  // kTupleInterpolation for "%(*)s"; kPercentInterpolation for "%%".
-  int param_index;
-};
-
-typedef ::std::vector<Interpolation> Interpolations;
-
-// Parses a matcher description string and returns a vector of
-// interpolations that appear in the string; generates non-fatal
-// failures iff 'description' is an invalid matcher description.
-// 'param_names' is a NULL-terminated array of parameter names in the
-// order they appear in the MATCHER_P*() parameter list.
-Interpolations ValidateMatcherDescription(
-    const char* param_names[], const char* description);
-
-// Returns the actual matcher description, given the matcher name,
-// user-supplied description template string, interpolations in the
-// string, and the printed values of the matcher parameters.
-string FormatMatcherDescription(
-    const char* matcher_name, const char* description,
-    const Interpolations& interp, const Strings& param_values);
+// Returns the description for a matcher defined using the MATCHER*()
+// macro where the user-supplied description string is "", if
+// 'negation' is false; otherwise returns the description of the
+// negation of the matcher.  'param_values' contains a list of strings
+// that are the print-out of the matcher's parameters.
+string FormatMatcherDescription(bool negation, const char* matcher_name,
+                                const Strings& param_values);
 
 }  // namespace internal
 
diff --git a/src/gmock-matchers.cc b/src/gmock-matchers.cc
index 0abca708..89007d9f 100644
--- a/src/gmock-matchers.cc
+++ b/src/gmock-matchers.cc
@@ -65,74 +65,6 @@ Matcher<internal::string>::Matcher(const char* s) {
 
 namespace internal {
 
-// Utilities for validating and formatting description strings in the
-// MATCHER*() macros.
-
-// Returns the 0-based index of the given parameter in the
-// NULL-terminated parameter array; if the parameter is "*", returns
-// kTupleInterpolation; if it's not found in the list, returns
-// kInvalidInterpolation.
-int GetParamIndex(const char* param_names[], const string& param_name) {
-  if (param_name == "*")
-    return kTupleInterpolation;
-
-  for (int i = 0; param_names[i] != NULL; i++) {
-    if (param_name == param_names[i])
-      return i;
-  }
-  return kInvalidInterpolation;
-}
-
-// Helper function used by ValidateMatcherDescription() to format
-// error messages.
-string FormatMatcherDescriptionSyntaxError(const char* description,
-                                           const char* error_pos) {
-  ::std::stringstream ss;
-  ss << "Syntax error at index " << (error_pos - description)
-     << " in matcher description \"" << description << "\": ";
-  return ss.str();
-}
-
-// Parses a matcher description string and returns a vector of
-// interpolations that appear in the string; generates non-fatal
-// failures iff 'description' is an invalid matcher description.
-// 'param_names' is a NULL-terminated array of parameter names in the
-// order they appear in the MATCHER_P*() parameter list.
-Interpolations ValidateMatcherDescription(
-    const char* param_names[], const char* description) {
-  Interpolations interps;
-  for (const char* p = description; *p != '\0';) {
-    if (SkipPrefix("%%", &p)) {
-      interps.push_back(Interpolation(p - 2, p, kPercentInterpolation));
-    } else if (SkipPrefix("%(", &p)) {
-      const char* const q = strstr(p, ")s");
-      if (q == NULL) {
-        // TODO(wan@google.com): change the source file location in
-        // the failure to point to where the MATCHER*() macro is used.
-        ADD_FAILURE() << FormatMatcherDescriptionSyntaxError(description, p - 2)
-                      << "an interpolation must end with \")s\", "
-                      << "but \"" << (p - 2) << "\" does not.";
-      } else {
-        const string param_name(p, q);
-        const int param_index = GetParamIndex(param_names, param_name);
-        if (param_index == kInvalidInterpolation) {
-          ADD_FAILURE() << FormatMatcherDescriptionSyntaxError(description, p)
-                        << "\"" << param_name
-                        << "\" is an invalid parameter name.";
-        } else {
-          interps.push_back(Interpolation(p - 2, q + 2, param_index));
-          p = q + 2;
-        }
-      }
-    } else {
-      EXPECT_NE(*p, '%') << FormatMatcherDescriptionSyntaxError(description, p)
-                         << "use \"%%\" instead of \"%\" to print \"%\".";
-      ++p;
-    }
-  }
-  return interps;
-}
-
 // Joins a vector of strings as if they are fields of a tuple; returns
 // the joined string.
 string JoinAsTuple(const Strings& fields) {
@@ -152,38 +84,17 @@ string JoinAsTuple(const Strings& fields) {
   }
 }
 
-// Returns the actual matcher description, given the matcher name,
-// user-supplied description template string, interpolations in the
-// string, and the printed values of the matcher parameters.
-string FormatMatcherDescription(
-    const char* matcher_name, const char* description,
-    const Interpolations& interp, const Strings& param_values) {
-  string result;
-  if (*description == '\0') {
-    // When the user supplies an empty description, we calculate one
-    // from the matcher name.
-    result = ConvertIdentifierNameToWords(matcher_name);
-    if (param_values.size() >= 1)
-      result += " " + JoinAsTuple(param_values);
-  } else {
-    // The end position of the last interpolation.
-    const char* last_interp_end = description;
-    for (size_t i = 0; i < interp.size(); i++) {
-      result.append(last_interp_end, interp[i].start_pos);
-      const int param_index = interp[i].param_index;
-      if (param_index == kTupleInterpolation) {
-        result += JoinAsTuple(param_values);
-      } else if (param_index == kPercentInterpolation) {
-        result += '%';
-      } else if (param_index != kInvalidInterpolation) {
-        result += param_values[param_index];
-      }
-      last_interp_end = interp[i].end_pos;
-    }
-    result += last_interp_end;
-  }
-
-  return result;
+// Returns the description for a matcher defined using the MATCHER*()
+// macro where the user-supplied description string is "", if
+// 'negation' is false; otherwise returns the description of the
+// negation of the matcher.  'param_values' contains a list of strings
+// that are the print-out of the matcher's parameters.
+string FormatMatcherDescription(bool negation, const char* matcher_name,
+                                const Strings& param_values) {
+  string result = ConvertIdentifierNameToWords(matcher_name);
+  if (param_values.size() >= 1)
+    result += " " + JoinAsTuple(param_values);
+  return negation ? "not (" + result + ")" : result;
 }
 
 }  // namespace internal
diff --git a/test/gmock-generated-matchers_test.cc b/test/gmock-generated-matchers_test.cc
index eebca8a0..3a028040 100644
--- a/test/gmock-generated-matchers_test.cc
+++ b/test/gmock-generated-matchers_test.cc
@@ -72,6 +72,7 @@ using testing::MatchResultListener;
 using testing::Ne;
 using testing::Not;
 using testing::Pointee;
+using testing::PrintToString;
 using testing::Ref;
 using testing::StaticAssertTypeEq;
 using testing::StrEq;
@@ -603,9 +604,8 @@ TEST(MatcherMacroTest, Works) {
   EXPECT_EQ("", Explain(m, 7));
 }
 
-// Tests explaining match result in a MATCHER* macro.
-
-MATCHER(IsEven2, "is even") {
+// This also tests that the description string can reference 'negation'.
+MATCHER(IsEven2, negation ? "is odd" : "is even") {
   if ((arg % 2) == 0) {
     // Verifies that we can stream to result_listener, a listener
     // supplied by the MATCHER macro implicitly.
@@ -617,7 +617,11 @@ MATCHER(IsEven2, "is even") {
   }
 }
 
-MATCHER_P2(EqSumOf, x, y, "") {
+// This also tests that the description string can reference matcher
+// parameters.
+MATCHER_P2(EqSumOf, x, y,
+           string(negation ? "doesn't equal" : "equals") + " the sum of " +
+           PrintToString(x) + " and " + PrintToString(y)) {
   if (arg == (x + y)) {
     *result_listener << "OK";
     return true;
@@ -631,6 +635,19 @@ MATCHER_P2(EqSumOf, x, y, "") {
   }
 }
 
+// Tests that the matcher description can reference 'negation' and the
+// matcher parameters.
+TEST(MatcherMacroTest, DescriptionCanReferenceNegationAndParameters) {
+  const Matcher<int> m1 = IsEven2();
+  EXPECT_EQ("is even", Describe(m1));
+  EXPECT_EQ("is odd", DescribeNegation(m1));
+
+  const Matcher<int> m2 = EqSumOf(5, 9);
+  EXPECT_EQ("equals the sum of 5 and 9", Describe(m2));
+  EXPECT_EQ("doesn't equal the sum of 5 and 9", DescribeNegation(m2));
+}
+
+// Tests explaining match result in a MATCHER* macro.
 TEST(MatcherMacroTest, CanExplainMatchResult) {
   const Matcher<int> m1 = IsEven2();
   EXPECT_EQ("OK", Explain(m1, 4));
@@ -641,29 +658,6 @@ TEST(MatcherMacroTest, CanExplainMatchResult) {
   EXPECT_EQ("diff == -1", Explain(m2, 4));
 }
 
-// Tests that the description string supplied to MATCHER() must be
-// valid.
-
-MATCHER(HasBadDescription, "Invalid%") {
-  // Uses arg to suppress "unused parameter" warning.
-  return arg==arg;
-}
-
-TEST(MatcherMacroTest,
-     CreatingMatcherWithBadDescriptionGeneratesNonfatalFailure) {
-  EXPECT_NONFATAL_FAILURE(
-      HasBadDescription(),
-      "Syntax error at index 7 in matcher description \"Invalid%\": "
-      "use \"%%\" instead of \"%\" to print \"%\".");
-}
-
-MATCHER(HasGoodDescription, "good") { return arg==arg; }
-
-TEST(MatcherMacroTest, AcceptsValidDescription) {
-  const Matcher<int> m = HasGoodDescription();
-  EXPECT_EQ("good", Describe(m));
-}
-
 // Tests that the body of MATCHER() can reference the type of the
 // value being matched.
 
@@ -723,29 +717,6 @@ TEST(MatcherPMacroTest, Works) {
   EXPECT_EQ("", Explain(m, 5));
 }
 
-// Tests that the description string supplied to MATCHER_P() must be
-// valid.
-
-MATCHER_P(HasBadDescription1, n, "not %(m)s good") {
-  return arg > n;
-}
-
-TEST(MatcherPMacroTest,
-     CreatingMatcherWithBadDescriptionGeneratesNonfatalFailure) {
-  EXPECT_NONFATAL_FAILURE(
-      HasBadDescription1(2),
-      "Syntax error at index 6 in matcher description \"not %(m)s good\": "
-      "\"m\" is an invalid parameter name.");
-}
-
-
-MATCHER_P(HasGoodDescription1, n, "good %(n)s") { return arg==arg; }
-
-TEST(MatcherPMacroTest, AcceptsValidDescription) {
-  const Matcher<int> m = HasGoodDescription1(5);
-  EXPECT_EQ("good 5", Describe(m));
-}
-
 // Tests that the description is calculated correctly from the matcher name.
 MATCHER_P(_is_Greater_Than32and_, n, "") { return arg > 32 && arg > n; }
 
@@ -789,32 +760,6 @@ TEST(MatcherPMacroTest, WorksWhenExplicitlyInstantiatedWithReference) {
 }
 
 
-// Tests that the description string supplied to MATCHER_Pn() must be
-// valid.
-
-MATCHER_P2(HasBadDescription2, m, n, "not %(good") {
-  return arg > m + n;
-}
-
-TEST(MatcherPnMacroTest,
-     CreatingMatcherWithBadDescriptionGeneratesNonfatalFailure) {
-  EXPECT_NONFATAL_FAILURE(
-      HasBadDescription2(3, 4),
-      "Syntax error at index 4 in matcher description \"not %(good\": "
-      "an interpolation must end with \")s\", but \"%(good\" does not.");
-}
-
-MATCHER_P2(HasComplexDescription, foo, bar,
-           "is as complex as %(foo)s %(bar)s (i.e. %(*)s or %%%(foo)s!)") {
-  return arg==arg;
-}
-
-TEST(MatcherPnMacroTest, AcceptsValidDescription) {
-  Matcher<int> m = HasComplexDescription(100, "ducks");
-  EXPECT_EQ("is as complex as 100 \"ducks\" (i.e. (100, \"ducks\") or %100!)",
-            Describe(m));
-}
-
 // Tests that the body of MATCHER_Pn() can reference the parameter
 // types.
 
diff --git a/test/gmock-matchers_test.cc b/test/gmock-matchers_test.cc
index 3b151dbd..dd2534f0 100644
--- a/test/gmock-matchers_test.cc
+++ b/test/gmock-matchers_test.cc
@@ -52,11 +52,7 @@
 namespace testing {
 
 namespace internal {
-string FormatMatcherDescriptionSyntaxError(const char* description,
-                                           const char* error_pos);
-int GetParamIndex(const char* param_names[], const string& param_name);
 string JoinAsTuple(const Strings& fields);
-bool SkipPrefix(const char* prefix, const char** pstr);
 }  // namespace internal
 
 namespace gmock_matchers_test {
@@ -126,21 +122,13 @@ using testing::_;
 using testing::internal::DummyMatchResultListener;
 using testing::internal::ExplainMatchFailureTupleTo;
 using testing::internal::FloatingEqMatcher;
-using testing::internal::FormatMatcherDescriptionSyntaxError;
-using testing::internal::GetParamIndex;
-using testing::internal::Interpolation;
-using testing::internal::Interpolations;
+using testing::internal::FormatMatcherDescription;
 using testing::internal::JoinAsTuple;
 using testing::internal::RE;
-using testing::internal::SkipPrefix;
 using testing::internal::StreamMatchResultListener;
 using testing::internal::String;
 using testing::internal::StringMatchResultListener;
 using testing::internal::Strings;
-using testing::internal::ValidateMatcherDescription;
-using testing::internal::kInvalidInterpolation;
-using testing::internal::kPercentInterpolation;
-using testing::internal::kTupleInterpolation;
 using testing::internal::linked_ptr;
 using testing::internal::scoped_ptr;
 using testing::internal::string;
@@ -3643,176 +3631,6 @@ TEST(ContainerEqExtraTest, CopiesNativeArrayParameter) {
   EXPECT_THAT(a1, m);
 }
 
-// Tests GetParamIndex().
-
-TEST(GetParamIndexTest, WorksForEmptyParamList) {
-  const char* params[] = { NULL };
-  EXPECT_EQ(kTupleInterpolation, GetParamIndex(params, "*"));
-  EXPECT_EQ(kInvalidInterpolation, GetParamIndex(params, "a"));
-}
-
-TEST(GetParamIndexTest, RecognizesStar) {
-  const char* params[] = { "a", "b", NULL };
-  EXPECT_EQ(kTupleInterpolation, GetParamIndex(params, "*"));
-}
-
-TEST(GetParamIndexTest, RecognizesKnownParam) {
-  const char* params[] = { "foo", "bar", NULL };
-  EXPECT_EQ(0, GetParamIndex(params, "foo"));
-  EXPECT_EQ(1, GetParamIndex(params, "bar"));
-}
-
-TEST(GetParamIndexTest, RejectsUnknownParam) {
-  const char* params[] = { "foo", "bar", NULL };
-  EXPECT_EQ(kInvalidInterpolation, GetParamIndex(params, "foobar"));
-}
-
-// Tests SkipPrefix().
-
-TEST(SkipPrefixTest, SkipsWhenPrefixMatches) {
-  const char* const str = "hello";
-
-  const char* p = str;
-  EXPECT_TRUE(SkipPrefix("", &p));
-  EXPECT_EQ(str, p);
-
-  p = str;
-  EXPECT_TRUE(SkipPrefix("hell", &p));
-  EXPECT_EQ(str + 4, p);
-}
-
-TEST(SkipPrefixTest, DoesNotSkipWhenPrefixDoesNotMatch) {
-  const char* const str = "world";
-
-  const char* p = str;
-  EXPECT_FALSE(SkipPrefix("W", &p));
-  EXPECT_EQ(str, p);
-
-  p = str;
-  EXPECT_FALSE(SkipPrefix("world!", &p));
-  EXPECT_EQ(str, p);
-}
-
-// Tests FormatMatcherDescriptionSyntaxError().
-TEST(FormatMatcherDescriptionSyntaxErrorTest, FormatsCorrectly) {
-  const char* const description = "hello%world";
-  EXPECT_EQ("Syntax error at index 5 in matcher description \"hello%world\": ",
-            FormatMatcherDescriptionSyntaxError(description, description + 5));
-}
-
-// Tests ValidateMatcherDescription().
-
-TEST(ValidateMatcherDescriptionTest, AcceptsEmptyDescription) {
-  const char* params[] = { "foo", "bar", NULL };
-  EXPECT_THAT(ValidateMatcherDescription(params, ""),
-              ElementsAre());
-}
-
-TEST(ValidateMatcherDescriptionTest,
-     AcceptsNonEmptyDescriptionWithNoInterpolation) {
-  const char* params[] = { "foo", "bar", NULL };
-  EXPECT_THAT(ValidateMatcherDescription(params, "a simple description"),
-              ElementsAre());
-}
-
-// The MATCHER*() macros trigger warning C4100 (unreferenced formal
-// parameter) in MSVC with -W4.  Unfortunately they cannot be fixed in
-// the macro definition, as the warnings are generated when the macro
-// is expanded and macro expansion cannot contain #pragma.  Therefore
-// we suppress them here.
-#ifdef _MSC_VER
-#pragma warning(push)
-#pragma warning(disable:4100)
-#endif
-
-// We use MATCHER_P3() to define a matcher for testing
-// ValidateMatcherDescription(); otherwise we'll end up with much
-// plumbing code.  This is not circular as
-// ValidateMatcherDescription() doesn't affect whether the matcher
-// matches a value or not.
-MATCHER_P3(EqInterpolation, start, end, index, "equals Interpolation%(*)s") {
-  return arg.start_pos == start && arg.end_pos == end &&
-      arg.param_index == index;
-}
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-
-TEST(ValidateMatcherDescriptionTest, AcceptsPercentInterpolation) {
-  const char* params[] = { "foo", NULL };
-  const char* const desc = "one %%";
-  EXPECT_THAT(ValidateMatcherDescription(params, desc),
-              ElementsAre(EqInterpolation(desc + 4, desc + 6,
-                                          kPercentInterpolation)));
-}
-
-TEST(ValidateMatcherDescriptionTest, AcceptsTupleInterpolation) {
-  const char* params[] = { "foo", "bar", "baz", NULL };
-  const char* const desc = "%(*)s after";
-  EXPECT_THAT(ValidateMatcherDescription(params, desc),
-              ElementsAre(EqInterpolation(desc, desc + 5,
-                                          kTupleInterpolation)));
-}
-
-TEST(ValidateMatcherDescriptionTest, AcceptsParamInterpolation) {
-  const char* params[] = { "foo", "bar", "baz", NULL };
-  const char* const desc = "a %(bar)s.";
-  EXPECT_THAT(ValidateMatcherDescription(params, desc),
-              ElementsAre(EqInterpolation(desc + 2, desc + 9, 1)));
-}
-
-TEST(ValidateMatcherDescriptionTest, AcceptsMultiplenterpolations) {
-  const char* params[] = { "foo", "bar", "baz", NULL };
-  const char* const desc = "%(baz)s %(foo)s %(bar)s";
-  EXPECT_THAT(ValidateMatcherDescription(params, desc),
-              ElementsAre(EqInterpolation(desc, desc + 7, 2),
-                          EqInterpolation(desc + 8, desc + 15, 0),
-                          EqInterpolation(desc + 16, desc + 23, 1)));
-}
-
-TEST(ValidateMatcherDescriptionTest, AcceptsRepeatedParams) {
-  const char* params[] = { "foo", "bar", NULL };
-  const char* const desc = "%(foo)s and %(foo)s";
-  EXPECT_THAT(ValidateMatcherDescription(params, desc),
-              ElementsAre(EqInterpolation(desc, desc + 7, 0),
-                          EqInterpolation(desc + 12, desc + 19, 0)));
-}
-
-TEST(ValidateMatcherDescriptionTest, RejectsUnknownParam) {
-  const char* params[] = { "a", "bar", NULL };
-  EXPECT_NONFATAL_FAILURE({
-    EXPECT_THAT(ValidateMatcherDescription(params, "%(foo)s"),
-                ElementsAre());
-  }, "Syntax error at index 2 in matcher description \"%(foo)s\": "
-     "\"foo\" is an invalid parameter name.");
-}
-
-TEST(ValidateMatcherDescriptionTest, RejectsUnfinishedParam) {
-  const char* params[] = { "a", "bar", NULL };
-  EXPECT_NONFATAL_FAILURE({
-    EXPECT_THAT(ValidateMatcherDescription(params, "%(foo)"),
-                ElementsAre());
-  }, "Syntax error at index 0 in matcher description \"%(foo)\": "
-     "an interpolation must end with \")s\", but \"%(foo)\" does not.");
-
-  EXPECT_NONFATAL_FAILURE({
-    EXPECT_THAT(ValidateMatcherDescription(params, "x%(a"),
-                ElementsAre());
-  }, "Syntax error at index 1 in matcher description \"x%(a\": "
-     "an interpolation must end with \")s\", but \"%(a\" does not.");
-}
-
-TEST(ValidateMatcherDescriptionTest, RejectsSinglePercent) {
-  const char* params[] = { "a", NULL };
-  EXPECT_NONFATAL_FAILURE({
-    EXPECT_THAT(ValidateMatcherDescription(params, "a %."),
-                ElementsAre());
-  }, "Syntax error at index 2 in matcher description \"a %.\": "
-     "use \"%%\" instead of \"%\" to print \"%\".");
-
-}
-
 // Tests JoinAsTuple().
 
 TEST(JoinAsTupleTest, JoinsEmptyTuple) {
@@ -3839,118 +3657,21 @@ TEST(JoinAsTupleTest, JoinsTenTuple) {
 
 TEST(FormatMatcherDescriptionTest, WorksForEmptyDescription) {
   EXPECT_EQ("is even",
-            FormatMatcherDescription("IsEven", "", Interpolations(),
-                                     Strings()));
+            FormatMatcherDescription(false, "IsEven", Strings()));
+  EXPECT_EQ("not (is even)",
+            FormatMatcherDescription(true, "IsEven", Strings()));
 
   const char* params[] = { "5" };
   EXPECT_EQ("equals 5",
-            FormatMatcherDescription("Equals", "", Interpolations(),
+            FormatMatcherDescription(false, "Equals",
                                      Strings(params, params + 1)));
 
   const char* params2[] = { "5", "8" };
   EXPECT_EQ("is in range (5, 8)",
-            FormatMatcherDescription("IsInRange", "", Interpolations(),
+            FormatMatcherDescription(false, "IsInRange",
                                      Strings(params2, params2 + 2)));
 }
 
-TEST(FormatMatcherDescriptionTest, WorksForDescriptionWithNoInterpolation) {
-  EXPECT_EQ("is positive",
-            FormatMatcherDescription("Gt0", "is positive", Interpolations(),
-                                     Strings()));
-
-  const char* params[] = { "5", "6" };
-  EXPECT_EQ("is negative",
-            FormatMatcherDescription("Lt0", "is negative", Interpolations(),
-                                     Strings(params, params + 2)));
-}
-
-TEST(FormatMatcherDescriptionTest,
-     WorksWhenDescriptionStartsWithInterpolation) {
-  const char* params[] = { "5" };
-  const char* const desc = "%(num)s times bigger";
-  const Interpolation interp[] = { Interpolation(desc, desc + 7, 0) };
-  EXPECT_EQ("5 times bigger",
-            FormatMatcherDescription("Foo", desc,
-                                     Interpolations(interp, interp + 1),
-                                     Strings(params, params + 1)));
-}
-
-TEST(FormatMatcherDescriptionTest,
-     WorksWhenDescriptionEndsWithInterpolation) {
-  const char* params[] = { "5", "6" };
-  const char* const desc = "is bigger than %(y)s";
-  const Interpolation interp[] = { Interpolation(desc + 15, desc + 20, 1) };
-  EXPECT_EQ("is bigger than 6",
-            FormatMatcherDescription("Foo", desc,
-                                     Interpolations(interp, interp + 1),
-                                     Strings(params, params + 2)));
-}
-
-TEST(FormatMatcherDescriptionTest,
-     WorksWhenDescriptionStartsAndEndsWithInterpolation) {
-  const char* params[] = { "5", "6" };
-  const char* const desc = "%(x)s <= arg <= %(y)s";
-  const Interpolation interp[] = {
-    Interpolation(desc, desc + 5, 0),
-    Interpolation(desc + 16, desc + 21, 1)
-  };
-  EXPECT_EQ("5 <= arg <= 6",
-            FormatMatcherDescription("Foo", desc,
-                                     Interpolations(interp, interp + 2),
-                                     Strings(params, params + 2)));
-}
-
-TEST(FormatMatcherDescriptionTest,
-     WorksWhenDescriptionDoesNotStartOrEndWithInterpolation) {
-  const char* params[] = { "5.2" };
-  const char* const desc = "has %(x)s cents";
-  const Interpolation interp[] = { Interpolation(desc + 4, desc + 9, 0) };
-  EXPECT_EQ("has 5.2 cents",
-            FormatMatcherDescription("Foo", desc,
-                                     Interpolations(interp, interp + 1),
-                                     Strings(params, params + 1)));
-}
-
-TEST(FormatMatcherDescriptionTest,
-     WorksWhenDescriptionContainsMultipleInterpolations) {
-  const char* params[] = { "5", "6" };
-  const char* const desc = "in %(*)s or [%(x)s, %(y)s]";
-  const Interpolation interp[] = {
-    Interpolation(desc + 3, desc + 8, kTupleInterpolation),
-    Interpolation(desc + 13, desc + 18, 0),
-    Interpolation(desc + 20, desc + 25, 1)
-  };
-  EXPECT_EQ("in (5, 6) or [5, 6]",
-            FormatMatcherDescription("Foo", desc,
-                                     Interpolations(interp, interp + 3),
-                                     Strings(params, params + 2)));
-}
-
-TEST(FormatMatcherDescriptionTest,
-     WorksWhenDescriptionContainsRepeatedParams) {
-  const char* params[] = { "9" };
-  const char* const desc = "in [-%(x)s, %(x)s]";
-  const Interpolation interp[] = {
-    Interpolation(desc + 5, desc + 10, 0),
-    Interpolation(desc + 12, desc + 17, 0)
-  };
-  EXPECT_EQ("in [-9, 9]",
-            FormatMatcherDescription("Foo", desc,
-                                     Interpolations(interp, interp + 2),
-                                     Strings(params, params + 1)));
-}
-
-TEST(FormatMatcherDescriptionTest,
-     WorksForDescriptionWithInvalidInterpolation) {
-  const char* params[] = { "9" };
-  const char* const desc = "> %(x)s %(x)";
-  const Interpolation interp[] = { Interpolation(desc + 2, desc + 7, 0)  };
-  EXPECT_EQ("> 9 %(x)",
-            FormatMatcherDescription("Foo", desc,
-                                     Interpolations(interp, interp + 1),
-                                     Strings(params, params + 1)));
-}
-
 // Tests PolymorphicMatcher::mutable_impl().
 TEST(PolymorphicMatcherTest, CanAccessMutableImpl) {
   PolymorphicMatcher<DivisibleByImpl> m(DivisibleByImpl(42));