From 80011bcf9df49902f87a513215c2c61649d135cc Mon Sep 17 00:00:00 2001
From: "Martin A. Brown" <martin@linux-ip.net>
Date: Tue, 23 Feb 2016 12:18:17 -0800
Subject: [PATCH] move generic function into BaseDoctype

---
 tldp/doctypes/common.py | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/tldp/doctypes/common.py b/tldp/doctypes/common.py
index 50f8509..307dbe3 100644
--- a/tldp/doctypes/common.py
+++ b/tldp/doctypes/common.py
@@ -33,6 +33,13 @@ class BaseDoctype(object):
         self.config = kwargs.get('config', None)
         assert None not in (self.source, self.output, self.config)
 
+    def build_precheck(self):
+        for tool, validator in self.required.items():
+            thing = getattr(self.config, tool, None)
+            assert thing is not None
+            assert validator(thing)
+        return True
+
     def generate(self):
         # -- the output directory gets to prepare; must return True
         #