[test] Exclude Python tests if Python not found

Author: dpiparo

roottest/root/ntuple/atlas-datavector/CMakeLists.txt

@@ -78,15 +78,17 @@ ROOTTEST_ADD_TEST(read
 # instantiation done by the Python bindings was leading to a faulty behaviour:
 # the user-provided class template "AtlasLikeDataVector<CustomStruct>" does not
 # correspond to what the compiler sees, so we need to inject this information.
-ROOT_ADD_PYUNITTEST(
-    rentry_getptr
-    rentry_getptr.py
-    GENERIC
-    PYTHON_DEPS pytest
-    FIXTURES_REQUIRED atlas_datavector_write_done)
+if(ROOT_pyroot_FOUND)
+    ROOT_ADD_PYUNITTEST(
+        rentry_getptr
+        rentry_getptr.py
+        GENERIC
+        PYTHON_DEPS pytest
+        FIXTURES_REQUIRED atlas_datavector_write_done)
 
-ROOT_ADD_PYUNITTEST(
-    template_instantiation
-    template_instantiation.py
-    GENERIC
-    PYTHON_DEPS pytest)
+    ROOT_ADD_PYUNITTEST(
+        template_instantiation
+        template_instantiation.py
+        GENERIC
+        PYTHON_DEPS pytest)
+endif()