tests and test fixes

fixes test case:
make sales invoice using customer that does not have credit_days_based_on 'Last Day Of Next Month'
so that it doesn't conflict with payment term due date

fix test case:
create purchase invoice with new supplier with credit_days_based_on
"Fixed Days" as the default "Last Day of Month" does not apply when
using payment terms
diff --git a/erpnext/accounts/doctype/purchase_invoice/test_purchase_invoice.py b/erpnext/accounts/doctype/purchase_invoice/test_purchase_invoice.py
index 3454a2e..f189bf8 100644
--- a/erpnext/accounts/doctype/purchase_invoice/test_purchase_invoice.py
+++ b/erpnext/accounts/doctype/purchase_invoice/test_purchase_invoice.py
@@ -6,7 +6,7 @@
 import unittest
 import frappe, erpnext
 import frappe.model
-from frappe.utils import cint, flt, today, nowdate
+from frappe.utils import cint, flt, today, nowdate, getdate, add_days
 import frappe.defaults
 from erpnext.stock.doctype.purchase_receipt.test_purchase_receipt import set_perpetual_inventory, \
 	test_records as pr_test_records
@@ -551,6 +551,38 @@
 		#check outstanding after advance cancellation
 		self.assertEqual(flt(pi.outstanding_amount), flt(pi.grand_total + pi.total_advance))
 
+	def test_gl_entry_based_on_payment_schedule(self):
+		pi = make_purchase_invoice(do_not_save=True, supplier="_Test Supplier P")
+		pi.append("payment_schedule", {
+			"due_date": add_days(nowdate(), 15),
+			"payment_amount": 100
+		})
+		pi.append("payment_schedule", {
+			"due_date": add_days(nowdate(), 45),
+			"payment_amount": 150
+		})
+
+		pi.save()
+		pi.submit()
+
+		gl_entries = frappe.db.sql("""select account, debit, credit, due_date
+			from `tabGL Entry` where voucher_type='Purchase Invoice' and voucher_no=%s
+			order by account asc, debit asc""", pi.name, as_dict=1)
+		self.assertTrue(gl_entries)
+
+		expected_gl_entries = sorted([
+			[pi.credit_to, 0.0, 100.0, add_days(nowdate(), 15)],
+			[pi.credit_to, 0.0, 150.0, add_days(nowdate(), 45)],
+			["_Test Account Cost for Goods Sold - _TC", 250.0, 0.0, None]
+		])
+
+		for i, gle in enumerate(sorted(gl_entries, key=lambda gle: gle.account)):
+			self.assertEquals(expected_gl_entries[i][0], gle.account)
+			self.assertEquals(expected_gl_entries[i][1], gle.debit)
+			self.assertEquals(expected_gl_entries[i][2], gle.credit)
+			self.assertEquals(getdate(expected_gl_entries[i][3]), getdate(gle.due_date))
+
+
 def unlink_payment_on_cancel_of_invoice(enable=1):
 	accounts_settings = frappe.get_doc("Accounts Settings")
 	accounts_settings.unlink_payment_on_cancellation_of_invoice = enable
diff --git a/erpnext/accounts/doctype/sales_invoice/test_sales_invoice.py b/erpnext/accounts/doctype/sales_invoice/test_sales_invoice.py
index bb4cab4..331aee9 100644
--- a/erpnext/accounts/doctype/sales_invoice/test_sales_invoice.py
+++ b/erpnext/accounts/doctype/sales_invoice/test_sales_invoice.py
@@ -1273,7 +1273,7 @@
 		return si
 	
 	def test_gl_entry_based_on_payment_schedule(self):
-		si = create_sales_invoice(do_not_save=True)
+		si = create_sales_invoice(do_not_save=True, customer="_Test Customer P")
 		si.append("payment_schedule", {
 			"due_date": add_days(nowdate(), 15),
 			"payment_amount": 20
@@ -1302,7 +1302,7 @@
 			self.assertEquals(expected_gl_entries[i][1], gle.debit)
 			self.assertEquals(expected_gl_entries[i][2], gle.credit)
 			self.assertEquals(getdate(expected_gl_entries[i][3]), getdate(gle.due_date))
-		
+
 
 def create_sales_invoice(**args):
 	si = frappe.new_doc("Sales Invoice")
diff --git a/erpnext/buying/doctype/supplier/test_records.json b/erpnext/buying/doctype/supplier/test_records.json
index d2b3995..fa728be 100644
--- a/erpnext/buying/doctype/supplier/test_records.json
+++ b/erpnext/buying/doctype/supplier/test_records.json
@@ -1,6 +1,12 @@
 [
  {
   "doctype": "Supplier",
+  "supplier_name": "_Test Supplier P",
+  "supplier_type": "_Test Supplier Type",
+  "credit_days_based_on": "Fixed Days"
+ },
+ {
+  "doctype": "Supplier",
   "supplier_name": "_Test Supplier with Country",
   "supplier_type": "_Test Supplier Type",
   "country": "Greece"
diff --git a/erpnext/selling/doctype/customer/test_records.json b/erpnext/selling/doctype/customer/test_records.json
index 94f14ed..43d6beb 100644
--- a/erpnext/selling/doctype/customer/test_records.json
+++ b/erpnext/selling/doctype/customer/test_records.json
@@ -1,6 +1,14 @@
 [
  {
   "customer_group": "_Test Customer Group",
+  "customer_name": "_Test Customer P",
+  "customer_type": "Individual",
+  "doctype": "Customer",
+  "territory": "_Test Territory",
+  "credit_days_based_on": "Fixed Days"
+ },
+ {
+  "customer_group": "_Test Customer Group",
   "customer_name": "_Test Customer",
   "customer_type": "Individual",
   "doctype": "Customer",