fixes in Test Cases
diff --git a/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.py b/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.py
index 8c23867..31213af 100644
--- a/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.py
+++ b/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.py
@@ -364,8 +364,6 @@
 			)
 
 		if gl_entries:
-			for d in gl_entries:
-				print d.account, d.debit, d.credit
 			from erpnext.accounts.general_ledger import make_gl_entries
 			make_gl_entries(gl_entries, cancel=(self.docstatus == 2))
 
diff --git a/erpnext/accounts/doctype/purchase_invoice/test_purchase_invoice.py b/erpnext/accounts/doctype/purchase_invoice/test_purchase_invoice.py
index b682205..d0fb3d9 100644
--- a/erpnext/accounts/doctype/purchase_invoice/test_purchase_invoice.py
+++ b/erpnext/accounts/doctype/purchase_invoice/test_purchase_invoice.py
@@ -246,13 +246,15 @@
 					"rate": 500,
 					"qty": 1,
 					"item_code": "_Test Item Home Desktop 100",
-					"expense_account": "_Test Account Cost for Goods Sold - _TC"
+					"expense_account": "_Test Account Cost for Goods Sold - _TC",
+					"cost_center": "_Test Cost Center - _TC"
 				},
 				{
 					"rate": 1500,
 					"qty": 1,
 					"item_code": "_Test Item Home Desktop 200",
-					"expense_account": "_Test Account Cost for Goods Sold - _TC"
+					"expense_account": "_Test Account Cost for Goods Sold - _TC",
+					"cost_center": "_Test Cost Center - _TC"
 				}
 			]
 		})
@@ -260,6 +262,15 @@
 		purchase_invoice.submit()		
 		self.assertEqual(frappe.db.get_value("Project", "_Test Project", "total_purchase_cost"), 2000)
 		
+		purchase_invoice1 = frappe.copy_doc(purchase_invoice)
+		purchase_invoice1.save()
+		purchase_invoice1.submit()
+		
+		self.assertEqual(frappe.db.get_value("Project", "_Test Project", "total_purchase_cost"), 4000)
+		
+		purchase_invoice1.cancel()		
+		self.assertEqual(frappe.db.get_value("Project", "_Test Project", "total_purchase_cost"), 2000)
+		
 		purchase_invoice.cancel()		
 		self.assertEqual(frappe.db.get_value("Project", "_Test Project", "total_purchase_cost"), 0)