[tests] conditionally disable tests requiring Python 3.6

configure.in

@@ -397,6 +397,31 @@ else
   HAS_LANDMARKS="no"
 fi
 
+# Python 3 (for analysis-scripts)
+########
+
+AC_MSG_CHECKING(for python3)
+
+PYTHON3_VERSION=$(python3 --version 2>/dev/null || echo "")
+if test -z "$PYTHON3_VERSION" ; then
+  AC_MSG_RESULT(not found. Some non-regression tests will be disabled.)
+  HAS_PYTHON36="no"
+else
+  AC_MSG_RESULT(found)
+  AC_MSG_CHECKING(for python3 >= 3.6)
+  PYTHON3_VERSION=$(echo "$PYTHON3_VERSION" | cut -d' ' -f2-)
+  case $PYTHON3_VERSION in
+  2.*|3.[[0-5]].*)
+     AC_MSG_RESULT(found $PYTHON3_VERSION (too old); some non-regression tests will be disabled)
+     HAS_PYTHON36="no"
+     ;;
+   *)
+     AC_MSG_RESULT(ok)
+     HAS_PYTHON36="yes"
+     ;;
+  esac
+fi
+
 ############
 # Platform #
 ############
@@ -978,6 +1003,7 @@ AC_SUBST(DEVELOPMENT)
 AC_SUBST(HAS_APRON)
 AC_SUBST(HAS_MPFR)
 AC_SUBST(HAS_LANDMARKS)
+AC_SUBST(HAS_PYTHON36)
 AC_SUBST(LABLGTK_VERSION)
 AC_SUBST(OCAMLBEST)
 AC_SUBST(OCAMLVERSION)

share/Makefile.config.in

@@ -128,6 +128,9 @@ HAS_MPFR ?=@HAS_MPFR@
 # landmarks
 HAS_LANDMARKS	?=@HAS_LANDMARKS@
 
+# python 3.6
+HAS_PYTHON36 ?=@HAS_PYTHON36@
+
 ##########################
 # Miscellaneous commands #
 ##########################
@@ -157,8 +160,12 @@ HAVE_BUILTIN_VA_LIST ?=@HAVE_BUILTIN_VA_LIST@
 # Non-plugin test directories containing some ML files to compile
 TEST_DIRS_AS_PLUGIN:=\
   dynamic dynamic_plugin journal saveload spec misc syntax cil \
-  pretty_printing builtins libc value fc_script
-TEST_DIRS_AS_PLUGIN+=jcdb
+  pretty_printing builtins libc value
+
+ifeq ($(HAS_PYTHON36),yes)
+TEST_DIRS_AS_PLUGIN+= fc_script jcdb
+endif
+
 PLUGIN_TESTS_LIST+=$(TEST_DIRS_AS_PLUGIN)
 
 ##########################