Test the user package registry

We teach the FindPackageTest to build a sample project that stores its
build tree in the user package registry using export(PACKAGE), and then
find it with find_package.

Tests/FindPackageTest/CMakeLists.txt

@@ -180,3 +180,16 @@ ENDIF()
 IF(NOT "1.2" VERSION_EQUAL "1.2.0.0")
   MESSAGE(SEND_ERROR "1.2 VERSION_EQUAL 1.2.0.0 is not true!")
 ENDIF()
+
+#-----------------------------------------------------------------------------
+# Test export(PACKAGE) with find_package.
+MESSAGE(STATUS "Preparing export(PACKAGE) test project")
+TRY_COMPILE(EXPORTER_COMPILED
+  ${FindPackageTest_BINARY_DIR}/Exporter
+  ${FindPackageTest_SOURCE_DIR}/Exporter
+  CMakeTestExportPackage dummy
+  OUTPUT_VARIABLE output)
+MESSAGE(STATUS "Searching for export(PACKAGE) test project")
+SET(CMakeTestExportPackage_DIR "" CACHE FILEPATH
+  "Wipe out find results for testing." FORCE)
+FIND_PACKAGE(CMakeTestExportPackage 1.${CMAKE_VERSION} EXACT REQUIRED)

Tests/FindPackageTest/Exporter/CMakeLists.txt

@@ -0,0 +1,12 @@
+cmake_minimum_required(VERSION 2.7.20090831)
+project(CMakeTestExportPackage C)
+
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/CMakeTestExportPackageConfig.cmake.in
+               ${CMAKE_CURRENT_BINARY_DIR}/CMakeTestExportPackageConfig.cmake
+               @ONLY)
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/CMakeTestExportPackageConfigVersion.cmake.in
+               ${CMAKE_CURRENT_BINARY_DIR}/CMakeTestExportPackageConfigVersion.cmake
+               @ONLY)
+export(PACKAGE CMakeTestExportPackage)
+
+add_executable(dummy dummy.c)

Tests/FindPackageTest/Exporter/CMakeTestExportPackageConfig.cmake.in

@@ -0,0 +1 @@
+# Test config file.

Tests/FindPackageTest/Exporter/CMakeTestExportPackageConfigVersion.cmake.in

@@ -0,0 +1,6 @@
+# Test config file.
+SET(PACKAGE_VERSION "1.@CMAKE_VERSION@")
+IF("${PACKAGE_FIND_VERSION}" VERSION_EQUAL "${PACKAGE_VERSION}")
+  SET(PACKAGE_VERSION_COMPATIBLE 1)
+  SET(PACKAGE_VERSION_EXACT 1)
+ENDIF()

Tests/FindPackageTest/Exporter/dummy.c

@@ -0,0 +1 @@
+int main() { return 0; }