check if cppformat is the master project or just used as dependency

Based on that information less intrusive option defaults are choosen.
Additionally, packaging support is omitted.

test/CMakeLists.txt

@@ -143,4 +143,14 @@ add_test(find-package-test ${CMAKE_CTEST_COMMAND}
   --build-generator ${CMAKE_GENERATOR}
   --build-makeprogram ${CMAKE_MAKE_PROGRAM}
   --build-options "-Dcppformat_DIR=${PROJECT_BINARY_DIR}"
-                  "-DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}")
+                  "-DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}")
+
+# test if the targets are findable when add_subdirectory is used
+add_test(add_subdirectory-test ${CMAKE_CTEST_COMMAND}
+  -C ${CMAKE_BUILD_TYPE}
+  --build-and-test
+  "${CMAKE_CURRENT_SOURCE_DIR}/add_subdirectory-test"
+  "${CMAKE_CURRENT_BINARY_DIR}/add_subdirectory-test"
+  --build-generator ${CMAKE_GENERATOR}
+  --build-makeprogram ${CMAKE_MAKE_PROGRAM}
+  --build-options "-DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}")

test/add_subdirectory-test/CMakeLists.txt

@@ -0,0 +1,13 @@
+cmake_minimum_required(VERSION 2.8.12)
+
+project(cppformat-test)
+
+add_subdirectory(../.. cppformat)
+
+add_executable(library-test "main.cpp")
+target_link_libraries(library-test cppformat)
+
+if (TARGET cppformat-header-only)
+  add_executable(header-only-test "main.cpp")
+  target_link_libraries(header-only-test cppformat-header-only)
+endif ()

test/add_subdirectory-test/main.cpp

@@ -0,0 +1,8 @@
+#include "cppformat/format.h"
+
+int main(int argc, char** argv)
+{
+  for(int i = 0; i < argc; ++i)
+    fmt::print("{}: {}\n", i, argv[i]);
+  return 0;
+}