Make ExportLanguages a subtest of the ObjectLibrary test

It was a subtest of the RunCMake.ObjectLibrary test. However, we need
to test a build with ExternalProject after running CMake, which RunCMake tests
do not do.

Tests/ObjectLibrary/CMakeLists.txt

@@ -58,3 +58,5 @@ target_compile_definitions(ABmain PUBLIC $<TARGET_PROPERTY:B,INTERFACE_COMPILE_D
 add_executable(UseABinternal ${dummy}
   $<TARGET_OBJECTS:ABmain> $<TARGET_OBJECTS:A> $<TARGET_OBJECTS:B>
   )
+
+add_subdirectory(ExportLanguages)

Tests/ObjectLibrary/ExportLanguages/CMakeLists.txt

@@ -0,0 +1,15 @@
+cmake_minimum_required(VERSION 2.8)
+project(ExportLanguages CXX)
+add_library(ExportLanguagesA OBJECT a.cxx)
+add_library(ExportLanguagesB STATIC a.c $<TARGET_OBJECTS:ExportLanguagesA>)
+
+# Verify that object library languages are propagated.
+export(TARGETS ExportLanguagesB NAMESPACE Exp FILE BExport.cmake)
+include(ExternalProject)
+ExternalProject_Add(ExportLanguagesTest
+  SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/ExportLanguagesTest"
+  BINARY_DIR "${CMAKE_CURRENT_BINARY_DIR}/ExportLanguagesTest"
+  DOWNLOAD_COMMAND ""
+  INSTALL_COMMAND ""
+)
+add_dependencies(ExportLanguagesTest ExportLanguagesA ExportLanguagesB)

Tests/ObjectLibrary/ExportLanguages/ExportLanguagesTest/CMakeLists.txt

@@ -0,0 +1,14 @@
+
+cmake_minimum_required(VERSION 2.8)
+
+project(ExportLanguagesTest)
+
+include(${CMAKE_CURRENT_BINARY_DIR}/../BExport.cmake)
+get_property(configs TARGET ExpExportLanguagesB PROPERTY IMPORTED_CONFIGURATIONS)
+foreach(c ${configs})
+  get_property(langs TARGET ExpExportLanguagesB PROPERTY IMPORTED_LINK_INTERFACE_LANGUAGES_${c})
+  list(FIND langs CXX pos)
+  if(${pos} LESS 0)
+    message(FATAL_ERROR "Target export does not list object library languages.")
+  endif()
+endforeach()

Tests/ObjectLibrary/ExportLanguages/a.c

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

Tests/RunCMake/ObjectLibrary/ExportLanguages.cmake

@@ -1,15 +0,0 @@
-enable_language(CXX)
-add_library(A OBJECT a.cxx)
-add_library(B STATIC a.c $<TARGET_OBJECTS:A>)
-
-# Verify that object library languages are propagated.
-export(TARGETS B NAMESPACE Exp FILE BExport.cmake)
-include(${CMAKE_CURRENT_BINARY_DIR}/BExport.cmake)
-get_property(configs TARGET ExpB PROPERTY IMPORTED_CONFIGURATIONS)
-foreach(c ${configs})
-  get_property(langs TARGET ExpB PROPERTY IMPORTED_LINK_INTERFACE_LANGUAGES_${c})
-  list(FIND langs CXX pos)
-  if(${pos} LESS 0)
-    message(FATAL_ERROR "Target export does not list object library languages.")
-  endif()
-endforeach()

Tests/RunCMake/ObjectLibrary/RunCMakeTest.cmake

@@ -6,7 +6,6 @@ run_cmake(BadSourceExpression3)
 run_cmake(BadObjSource1)
 run_cmake(BadObjSource2)
 run_cmake(Export)
-run_cmake(ExportLanguages)
 run_cmake(Import)
 run_cmake(Install)
 run_cmake(LinkObjLHS)