CTest: Fail early without PROJECT_BINARY_DIR (#14005)

Do not use PROJECT_BINARY_DIR before it is defined.  If it is not
defined when needed, fail with an error message suggesting that the
project() command be invoked first.

Modules/CTestTargets.cmake

@@ -16,6 +16,10 @@ if(NOT RUN_FROM_CTEST_OR_DART)
   message(FATAL_ERROR "Do not incldue CTestTargets.cmake directly")
 endif()
 
+if(NOT PROJECT_BINARY_DIR)
+  message(FATAL_ERROR "Do not include(CTest) before calling project().")
+endif()
+
 # make directories in the binary tree
 file(MAKE_DIRECTORY ${PROJECT_BINARY_DIR}/Testing/Temporary)
 get_filename_component(CMAKE_HOST_PATH ${CMAKE_COMMAND} PATH)

Tests/RunCMake/CMakeLists.txt

@@ -52,6 +52,7 @@ if(XCODE_VERSION AND "${XCODE_VERSION}" VERSION_LESS 3)
 endif()
 
 add_RunCMake_test(CMP0019)
+add_RunCMake_test(CTest)
 if(UNIX AND "${CMAKE_TEST_GENERATOR}" MATCHES "Unix Makefiles")
   add_RunCMake_test(CompilerChange)
 endif()

Tests/RunCMake/CTest/BeforeProject-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/CTest/BeforeProject-stderr.txt

@@ -0,0 +1,6 @@
+CMake Error at .*/Modules/CTest.cmake:[0-9]+ \(build_command\):
+  build_command\(\) requires CMAKE_MAKE_PROGRAM to be defined.  Call project\(\)
+  or enable_language\(\) first.
+Call Stack \(most recent call first\):
+  BeforeProject.cmake:[0-9]+ \(include\)
+  CMakeLists.txt:[0-9]+ \(include\)

Tests/RunCMake/CTest/BeforeProject.cmake

@@ -0,0 +1,2 @@
+include(CTest)
+project(${RunCMake_TEST} NONE)

Tests/RunCMake/CTest/CMakeLists.txt

@@ -0,0 +1,5 @@
+cmake_minimum_required(VERSION 2.8)
+if(NOT NoProject)
+  project(${RunCMake_TEST} NONE)
+endif()
+include(${RunCMake_TEST}.cmake)

Tests/RunCMake/CTest/RunCMakeTest.cmake

@@ -0,0 +1,5 @@
+include(RunCMake)
+
+set(RunCMake_TEST_OPTIONS -DNoProject=1)
+run_cmake(BeforeProject)
+unset(RunCMake_TEST_OPTIONS)