folly:wangle: centralize FindGMock.cmake

Summary:
move the FindGMock to the common cmake library and adjust
folly and wangle to consume it from there.

Reviewed By: strager

Differential Revision: D14710329

fbshipit-source-id: 35ac9d6d2ec03468f389f5b9f1c126b007c7c798

CMake/FindGMock.cmake

-#
-# Find libgmock
-#
-#  LIBGMOCK_DEFINES     - List of defines when using libgmock.
-#  LIBGMOCK_INCLUDE_DIR - where to find gmock/gmock.h, etc.
-#  LIBGMOCK_LIBRARIES   - List of libraries when using libgmock.
-#  LIBGMOCK_FOUND       - True if libgmock found.
-
-IF (LIBGMOCK_INCLUDE_DIR)
-  # Already in cache, be silent
-  SET(LIBGMOCK_FIND_QUIETLY TRUE)
-ENDIF ()
-
-FIND_PATH(LIBGMOCK_INCLUDE_DIR gmock/gmock.h)
-
-FIND_LIBRARY(LIBGMOCK_MAIN_LIBRARY_DEBUG NAMES gmock_maind)
-FIND_LIBRARY(LIBGMOCK_MAIN_LIBRARY_RELEASE NAMES gmock_main)
-FIND_LIBRARY(LIBGMOCK_LIBRARY_DEBUG NAMES gmockd)
-FIND_LIBRARY(LIBGMOCK_LIBRARY_RELEASE NAMES gmock)
-FIND_LIBRARY(LIBGTEST_LIBRARY_DEBUG NAMES gtestd)
-FIND_LIBRARY(LIBGTEST_LIBRARY_RELEASE NAMES gtest)
-
-find_package(Threads REQUIRED)
-INCLUDE(SelectLibraryConfigurations)
-SELECT_LIBRARY_CONFIGURATIONS(LIBGMOCK_MAIN)
-SELECT_LIBRARY_CONFIGURATIONS(LIBGMOCK)
-SELECT_LIBRARY_CONFIGURATIONS(LIBGTEST)
-
-set(LIBGMOCK_LIBRARIES
-  ${LIBGMOCK_MAIN_LIBRARY}
-  ${LIBGMOCK_LIBRARY}
-  ${LIBGTEST_LIBRARY}
-  Threads::Threads
-)
-
-if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
-  # The GTEST_LINKED_AS_SHARED_LIBRARY macro must be set properly on Windows.
-  #
-  # There isn't currently an easy way to determine if a library was compiled as
-  # a shared library on Windows, so just assume we've been built against a
-  # shared build of gmock for now.
-  SET(LIBGMOCK_DEFINES "GTEST_LINKED_AS_SHARED_LIBRARY=1" CACHE STRING "")
-endif()
-
-# handle the QUIETLY and REQUIRED arguments and set LIBGMOCK_FOUND to TRUE if
-# all listed variables are TRUE
-INCLUDE(FindPackageHandleStandardArgs)
-FIND_PACKAGE_HANDLE_STANDARD_ARGS(
-  GMock
-  DEFAULT_MSG
-  LIBGMOCK_MAIN_LIBRARY
-  LIBGMOCK_LIBRARY
-  LIBGTEST_LIBRARY
-  LIBGMOCK_LIBRARIES
-  LIBGMOCK_INCLUDE_DIR
-)
-
-MARK_AS_ADVANCED(
-  LIBGMOCK_DEFINES
-  LIBGMOCK_MAIN_LIBRARY
-  LIBGMOCK_LIBRARY
-  LIBGTEST_LIBRARY
-  LIBGMOCK_LIBRARIES
-  LIBGMOCK_INCLUDE_DIR
-)

build/fbcode_builder/CMake/FindGMock.cmake

+#
+# Find libgmock
+#
+#  LIBGMOCK_DEFINES     - List of defines when using libgmock.
+#  LIBGMOCK_INCLUDE_DIR - where to find gmock/gmock.h, etc.
+#  LIBGMOCK_LIBRARIES   - List of libraries when using libgmock.
+#  LIBGMOCK_FOUND       - True if libgmock found.
+
+IF (LIBGMOCK_INCLUDE_DIR)
+  # Already in cache, be silent
+  SET(LIBGMOCK_FIND_QUIETLY TRUE)
+ENDIF ()
+
+find_package(GTest CONFIG QUIET)
+if (TARGET GTest::gmock)
+  get_target_property(LIBGMOCK_DEFINES GTest::gtest INTERFACE_COMPILE_DEFINITIONS)
+  if (NOT ${LIBGMOCK_DEFINES})
+    # Explicitly set to empty string if not found to avoid it being
+    # set to NOTFOUND and breaking compilation
+    set(LIBGMOCK_DEFINES "")
+  endif()
+  get_target_property(LIBGMOCK_INCLUDE_DIR GTest::gtest INTERFACE_INCLUDE_DIRECTORIES)
+  set(LIBGMOCK_LIBRARIES GTest::gmock_main GTest::gmock GTest::gtest)
+  set(LIBGMOCK_FOUND ON)
+  message(STATUS "Found gmock via config, defines=${LIBGMOCK_DEFINES}, include=${LIBGMOCK_INCLUDE_DIR}, libs=${LIBGMOCK_LIBRARIES}")
+else()
+
+  FIND_PATH(LIBGMOCK_INCLUDE_DIR gmock/gmock.h)
+
+  FIND_LIBRARY(LIBGMOCK_MAIN_LIBRARY_DEBUG NAMES gmock_maind)
+  FIND_LIBRARY(LIBGMOCK_MAIN_LIBRARY_RELEASE NAMES gmock_main)
+  FIND_LIBRARY(LIBGMOCK_LIBRARY_DEBUG NAMES gmockd)
+  FIND_LIBRARY(LIBGMOCK_LIBRARY_RELEASE NAMES gmock)
+  FIND_LIBRARY(LIBGTEST_LIBRARY_DEBUG NAMES gtestd)
+  FIND_LIBRARY(LIBGTEST_LIBRARY_RELEASE NAMES gtest)
+
+  find_package(Threads REQUIRED)
+  INCLUDE(SelectLibraryConfigurations)
+  SELECT_LIBRARY_CONFIGURATIONS(LIBGMOCK_MAIN)
+  SELECT_LIBRARY_CONFIGURATIONS(LIBGMOCK)
+  SELECT_LIBRARY_CONFIGURATIONS(LIBGTEST)
+
+  set(LIBGMOCK_LIBRARIES
+    ${LIBGMOCK_MAIN_LIBRARY}
+    ${LIBGMOCK_LIBRARY}
+    ${LIBGTEST_LIBRARY}
+    Threads::Threads
+  )
+
+  if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
+    # The GTEST_LINKED_AS_SHARED_LIBRARY macro must be set properly on Windows.
+    #
+    # There isn't currently an easy way to determine if a library was compiled as
+    # a shared library on Windows, so just assume we've been built against a
+    # shared build of gmock for now.
+    SET(LIBGMOCK_DEFINES "GTEST_LINKED_AS_SHARED_LIBRARY=1" CACHE STRING "")
+  endif()
+
+  # handle the QUIETLY and REQUIRED arguments and set LIBGMOCK_FOUND to TRUE if
+  # all listed variables are TRUE
+  INCLUDE(FindPackageHandleStandardArgs)
+  FIND_PACKAGE_HANDLE_STANDARD_ARGS(
+    GMock
+    DEFAULT_MSG
+    LIBGMOCK_MAIN_LIBRARY
+    LIBGMOCK_LIBRARY
+    LIBGTEST_LIBRARY
+    LIBGMOCK_LIBRARIES
+    LIBGMOCK_INCLUDE_DIR
+  )
+
+  MARK_AS_ADVANCED(
+    LIBGMOCK_DEFINES
+    LIBGMOCK_MAIN_LIBRARY
+    LIBGMOCK_LIBRARY
+    LIBGTEST_LIBRARY
+    LIBGMOCK_LIBRARIES
+    LIBGMOCK_INCLUDE_DIR
+  )
+endif()