fixes cmake for mac, adds define option for building tests

CMakeLists.txt

@@ -10,7 +10,6 @@
 # properly installed. Build using Visual Studio requires msbuild shell.
 #
 # Example Usage:
-#   cd build/cmake
 #   mkdir buildproducts
 #   cd buildproducts
 #   cmake ..
@@ -29,7 +28,7 @@
 # Generic Invocation:
 #   cmake -E make_directory buildprod
 #   cd build
-#   cmake -G GENERATOR -DCMAKE_BUILD_TYPE=Release ..
+#   cmake -G GENERATOR -DCMAKE_BUILD_TYPE=Release -DBUILD_TESTS=1 ..
 #   cmake --build . --target SOME_TARGET --config Release
 #
 # More information:
@@ -42,8 +41,10 @@ cmake_minimum_required (VERSION 2.8.8)
 
 project(EPANET)
 add_subdirectory(tools/epanet-output)
-add_subdirectory(tests)
 
+IF (BUILD_TESTS)
+  add_subdirectory(tests)
+ENDIF (BUILD_TESTS)
 
 # Sets for output directory for executables and libraries.
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
@@ -55,8 +56,8 @@ SET(CMAKE_POSITION_INDEPENDENT_CODE ON)
 
 
 IF (APPLE)
-  SET(CMAKE_INSTALL_NAME_DIR @executable_path)
-  SET(CMAKE_BUILD_WITH_INSTALL_RPATH ON)
+SET(INSTALL_NAME_DIR @executable_path/../lib)
+SET(CMAKE_MACOSX_RPATH 1)
 ENDIF (APPLE)
 
 IF (MSVC)