Tests: Add tests for CMakePrintHelpers

Add three tests in Tests/RunCMake/PrintHelpers, meant to verify
basic functionality of the module. Tests are:

* Variables: Test the results of a cmake_print_variables()
  call on two variables set within the test script.

* Properties: Test cmake_print_properties() calls on a pair
  of SOURCES and a pair of TARGETS, printing some basic properties.

* PropertiesSources: Specifically verify the results of a
  cmake_print_properties() call for the SOURCES property of a
  TARGET. Prior to the fix introduced alongside these tests, it
  was a known bug that such a request caused a FATAL_ERROR.

1 files changed, 7 insertions, 0 deletions

diff --git a/Tests/RunCMake/PrintHelpers/something.c b/Tests/RunCMake/PrintHelpers/something.c
new file mode 100644
index 0000000..a2bc425
--- /dev/null
+++ b/Tests/RunCMake/PrintHelpers/something.c
@@ -0,0 +1,7 @@
+#include "something.h"
+
+int main()
+{
+  nothing();
+  return 0;
+}