FindPython: Test existence of imported targets

Tests/FindPython/Python/CMakeLists.txt

@@ -9,6 +9,14 @@ if (NOT Python_FOUND)
   message (FATAL_ERROR "Fail to found Python 3")
 endif()
 
+if(NOT TARGET Python::Interpreter)
+  message(SEND_ERROR "Python::Interpreter not found")
+endif()
+
+if(NOT TARGET Python::Python)
+  message(SEND_ERROR "Python::Python not found")
+endif()
+
 Python_add_library (spam3 MODULE ../spam.c)
 target_compile_definitions (spam3 PRIVATE PYTHON3)
 

Tests/FindPython/Python2/CMakeLists.txt

@@ -14,6 +14,14 @@ if (NOT Python2_FOUND)
   message (FATAL_ERROR "Fail to found Python 2")
 endif()
 
+if(NOT TARGET Python2::Interpreter)
+  message(SEND_ERROR "Python2::Interpreter not found")
+endif()
+
+if(NOT TARGET Python2::Python)
+  message(SEND_ERROR "Python2::Python not found")
+endif()
+
 Python2_add_library (spam2 MODULE ../spam.c)
 target_compile_definitions (spam2 PRIVATE PYTHON2)
 

Tests/FindPython/Python3/CMakeLists.txt

@@ -14,6 +14,14 @@ if (NOT Python3_FOUND)
   message (FATAL_ERROR "Fail to found Python 3")
 endif()
 
+if(NOT TARGET Python3::Interpreter)
+  message(SEND_ERROR "Python2::Interpreter not found")
+endif()
+
+if(NOT TARGET Python3::Python)
+  message(SEND_ERROR "Python2::Python not found")
+endif()
+
 Python3_add_library (spam3 MODULE ../spam.c)
 target_compile_definitions (spam3 PRIVATE PYTHON3)