Fix required computation when line has no purchase

issue7281
review41221002

purchase.py

@@ -91,9 +91,10 @@ class AnalyticAccountEntry:
         PurchaseLine = pool.get('purchase.line')
         required = super(AnalyticAccountEntry, self).on_change_with_required(
             name)
-        if (self.origin and isinstance(self.origin, PurchaseLine)
-                and self.origin.purchase.state in ['cancel', 'draft']):
-            return False
+        if isinstance(self.origin, PurchaseLine):
+            if (not self.origin.purchase
+                    or self.origin.purchase.state in ['cancel', 'draft']):
+                return False
         return required
 
     @fields.depends('origin')

tests/scenario_analytic_purchase.rst

@@ -112,11 +112,16 @@ Purchase with analytic accounts::
     >>> mandatory_entry.root == mandatory_root
     True
     >>> bool(mandatory_entry.required)
-    True
+    False
     >>> purchase_line.product = product
     >>> purchase_line.quantity = 5
     >>> mandatory_entry.account = mandatory_analytic_account
     >>> purchase.click('quote')
+    >>> purchase_line, = purchase.lines
+    >>> mandatory_entry, = [a for a in purchase_line.analytic_accounts
+    ...     if a.root == mandatory_root]
+    >>> bool(mandatory_entry.required)
+    True
     >>> purchase.click('confirm')
     >>> purchase.click('process')