Show link to txn as field when viewing trainwreck item

tailbone/views/trainwreck/base.py

@@ -30,7 +30,7 @@ import six
 
 from rattail.time import localtime
 
-from webhelpers2.html import HTML
+from webhelpers2.html import HTML, tags
 
 from tailbone.db import Session, TrainwreckSession, ExtraTrainwreckSessions
 from tailbone.views import MasterView
@@ -128,6 +128,7 @@ class TransactionView(MasterView):
     ]
 
     row_form_fields = [
+        'transaction',
         'sequence',
         'item_type',
         'item_scancode',
@@ -271,9 +272,15 @@ class TransactionView(MasterView):
         if row.void:
             return 'warning'
 
+    def get_row_instance_title(self, instance):
+        return "Trainwreck Line Item"
+
     def configure_row_form(self, f):
         super(TransactionView, self).configure_row_form(f)
 
+        # transaction
+        f.set_renderer('transaction', self.render_transaction)
+
         # quantity fields
         f.set_type('unit_quantity', 'quantity')
 
@@ -287,6 +294,12 @@ class TransactionView(MasterView):
         # discounts
         f.set_renderer('discounts', self.render_discounts)
 
+    def render_transaction(self, item, field):
+        txn = getattr(item, field)
+        text = six.text_type(txn)
+        url = self.get_action_url('view', txn)
+        return tags.link_to(text, url)
+
     def render_discounts(self, item, field):
         if not item.discounts:
             return