modules : added warning if a user tries to add prerequisite with dotkit

lib/spack/spack/modules.py

@@ -382,11 +382,11 @@ def module_specific_content(self, configuration):
         return tuple()
 
     def autoload(self, spec):
-        m = TclModule(spec)
+        m = type(self)(spec)
         return self.autoload_format.format(module_file=m.use_name)
 
     def prerequisite(self, spec):
-        m = TclModule(spec)
+        m = type(self)(spec)
         return self.prerequisite_format.format(module_file=m.use_name)
 
     def process_environment_command(self, env):
@@ -449,6 +449,11 @@ def header(self):
                 header += '#h %s\n' % line
         return header
 
+    def prerequisite(self, spec):
+        tty.warn('prerequisites:  not supported by dotkit module files')
+        tty.warn('\tYou may want to check  ~/.spack/modules.yaml')
+        return ''
+
 
 class TclModule(EnvModule):
     name = 'tcl'