trailing_return_mock

.github/workflows/ci.yml

@@ -904,6 +904,7 @@ jobs:
             cxx_standard: 20,
             cxx_asan: true,
             libcxx: false,
+            cxx_flags: "-Wno-gnu-zero-variadic-macro-arguments"
           }
           - {
             name: "Linux Clang 10 C++11 / libc++",
@@ -940,6 +941,7 @@ jobs:
             cxx_standard: 20,
             cxx_asan: true,
             libcxx: true,
+            cxx_flags: "-Wno-gnu-zero-variadic-macro-arguments"
           }
 
           # Clang-11
@@ -978,6 +980,7 @@ jobs:
             cxx_standard: 20,
             cxx_asan: true,
             libcxx: false,
+            cxx_flags: "-Wno-gnu-zero-variadic-macro-arguments"
           }
           - {
             name: "Linux Clang 11 C++11 / libc++",
@@ -1014,6 +1017,7 @@ jobs:
             cxx_standard: 20,
             cxx_asan: true,
             libcxx: true,
+            cxx_flags: "-Wno-gnu-zero-variadic-macro-arguments"
           }
 
           # Clang-12
@@ -1052,6 +1056,7 @@ jobs:
             cxx_standard: 20,
             cxx_asan: true,
             libcxx: false,
+            cxx_flags: "-Wno-gnu-zero-variadic-macro-arguments"
           }
           - {
             name: "Linux Clang 12 C++11 / libc++",
@@ -1088,6 +1093,7 @@ jobs:
             cxx_standard: 20,
             cxx_asan: true,
             libcxx: true,
+            cxx_flags: "-Wno-gnu-zero-variadic-macro-arguments"
           }
 
           # Clang-13
@@ -1126,6 +1132,7 @@ jobs:
             cxx_standard: 20,
             cxx_asan: true,
             libcxx: false,
+            cxx_flags: "-Wno-gnu-zero-variadic-macro-arguments"
           }
           - {
             name: "Linux Clang 13 C++11 / libc++",
@@ -1162,6 +1169,7 @@ jobs:
             cxx_standard: 20,
             cxx_asan: true,
             libcxx: true,
+            cxx_flags: "-Wno-gnu-zero-variadic-macro-arguments"
           }
 
           # Clang-14
@@ -1628,24 +1636,52 @@ jobs:
             cc: "cl", cxx: "cl",
             cxx_standard: 11,
           }
+          - {
+              name: "Windows MSVC 2022 C++11 preprocessor",
+              os: windows-2022,
+              cc: "cl", cxx: "cl",
+              cxx_standard: 11,
+              cxx_flags: "/Zc:preprocessor"
+          }
           - {
             name: "Windows MSVC 2022 C++14",
             os: windows-2022,
             cc: "cl", cxx: "cl",
             cxx_standard: 14,
           }
+          - {
+            name: "Windows MSVC 2022 C++14 preprocessor",
+            os: windows-2022,
+            cc: "cl", cxx: "cl",
+            cxx_standard: 14,
+            cxx_flags: "/Zc:preprocessor"
+          }
           - {
             name: "Windows MSVC 2022 C++17",
             os: windows-2022,
             cc: "cl", cxx: "cl",
             cxx_standard: 17,
           }
+          - {
+            name: "Windows MSVC 2022 C++17 preprocessor",
+            os: windows-2022,
+            cc: "cl", cxx: "cl",
+            cxx_standard: 17,
+            cxx_flags: "/Zc:preprocessor"
+          }
           - {
             name: "Windows MSVC 2022 C++20",
             os: windows-2022,
             cc: "cl", cxx: "cl",
             cxx_standard: 20,
           }
+          - {
+            name: "Windows MSVC 2022 C++20 preprocessor",
+            os: windows-2022,
+            cc: "cl", cxx: "cl",
+            cxx_standard: 20,
+            cxx_flags: "/Zc:preprocessor"
+          }
 
           # MSVC 2019
           - {
@@ -1654,24 +1690,52 @@ jobs:
             cc: "cl", cxx: "cl",
             cxx_standard: 11,
           }
+          - {
+            name: "Windows MSVC 2019 C++11 preprocessor",
+            os: windows-2019,
+            cc: "cl", cxx: "cl",
+            cxx_standard: 11,
+            cxx_flags: "/Zc:preprocessor"
+          }
           - {
             name: "Windows MSVC 2019 C++14",
             os: windows-2019,
             cc: "cl", cxx: "cl",
             cxx_standard: 14,
           }
+          - {
+            name: "Windows MSVC 2019 C++14 preprocessor",
+            os: windows-2019,
+            cc: "cl", cxx: "cl",
+            cxx_standard: 14,
+            cxx_flags: "/Zc:preprocessor"
+          }
           - {
             name: "Windows MSVC 2019 C++17",
             os: windows-2019,
             cc: "cl", cxx: "cl",
             cxx_standard: 17,
           }
+          - {
+            name: "Windows MSVC 2019 C++17 preprocessor",
+            os: windows-2019,
+            cc: "cl", cxx: "cl",
+            cxx_standard: 17,
+            cxx_flags: "/Zc:preprocessor"
+          }
           - {
             name: "Windows MSVC 2019 C++20",
             os: windows-2019,
             cc: "cl", cxx: "cl",
             cxx_standard: 20,
           }
+          - {
+            name: "Windows MSVC 2019 C++20 preprocessor",
+            os: windows-2019,
+            cc: "cl", cxx: "cl",
+            cxx_standard: 20,
+            cxx_flags: "/Zc:preprocessor"
+          }
     steps:
       - uses: actions/checkout@v4
 
@@ -1698,6 +1762,10 @@ jobs:
         shell: bash
         run: |
           STD=${{ matrix.config.cxx_standard }}
+          if [ -n "${{ matrix.config.cxx_flags }}" ]
+          then
+            cxx_flags="${{matrix.config.cxx_flags }}"
+          fi
           if [ "x${{ matrix.config.libcxx }}" == "xtrue" ]
           then
             cxx_flags="${cxx_flags} -stdlib=libc++  -Wno-unused-command-line-argument"

ChangeLog

@@ -1,3 +1,25 @@
+	* Added mocking macros that infers function arity from a trailing return
+	  type syntax signature.
+
+	    MAKE_MOCK(name, signature {, specifiers})
+	    MAKE_CONST_MOCK(name, signature {, specifiers})
+	    MAKE_STDMETHOD_MOCK(name, signature {, specifiers})
+
+	  Note that these only work with trailing return type syntax. Examples
+	  of specifiers are 'override', 'final' and 'noexcept'
+
+	  The preprocessor is limited and can only handle nullary functions,
+	  i.e. functions that do not accept any arguments, in some cases.
+
+	  MSVC handles nullary functions when compiling with /Zc:preprocessor
+	  with MSVC 19.40 (VS 17.10) or later.
+
+	  Gcc and Clang always handles nullary functions when compiling with
+	  C++20 or later, and when enabling a gcc extension by compiling with
+	  -std=gnu++11/14/17 and defining the macro TROMPELOEIL_HAS_GCC_PP before
+	  #include:ing the trompeloeil headers.
+
+
 	* Added .RT_TIMES() to exceptations, which works like .TIMES()
 	  but where the limits are only known at runtime. Thank you
 	  Dominic Koepke for submitting the implementation.

README.md

@@ -59,9 +59,9 @@ void interface_func(Interface*); // function to test
 class Mock : public Interface
 {
 public:
-  MAKE_MOCK2(foo, bool(int, std::string&),override);
-  MAKE_MOCK1(bar, bool(int),override);
-  MAKE_MOCK1(bar, bool(std::string),override);
+  MAKE_MOCK(foo, auto (int, std::string&) -> bool, override);
+  MAKE_MOCK(bar, auto (int) -> bool, override);
+  MAKE_MOCK(bar, auto (std::string) -> bool, override);
   MAKE_MOCK0(baz, void()); // not from Interface
 };