Remove 'single_price' field from supplier part

- Instead we will rely entirely on the SupplierPriceBreak model

InvenTree/build/migrations/0014_auto_20190518_1543.py

@@ -0,0 +1,19 @@
+# Generated by Django 2.2 on 2019-05-18 05:43
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('build', '0013_build_take_from'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='build',
+            name='take_from',
+            field=models.ForeignKey(blank=True, help_text='Select location to take stock from for this build (leave blank to take from any stock location)', null=True, on_delete=django.db.models.deletion.SET_NULL, related_name='sourcing_builds', to='stock.StockLocation'),
+        ),
+    ]

InvenTree/part/forms.py

@@ -155,7 +155,6 @@ class EditSupplierPartForm(HelperForm):
             'MPN',
             'URL',
             'note',
-            'single_price',
             'base_cost',
             'multiple',
             'minimum',

InvenTree/part/migrations/0026_remove_supplierpart_single_price.py

@@ -0,0 +1,17 @@
+# Generated by Django 2.2 on 2019-05-18 05:43
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('part', '0025_auto_20190515_0012'),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name='supplierpart',
+            name='single_price',
+        ),
+    ]

InvenTree/part/models.py

@@ -816,7 +816,6 @@ class SupplierPart(models.Model):
         URL: Link to external website for this part
         description: Descriptive notes field
         note: Longer form note field
-        single_price: Default price for a single unit
         base_cost: Base charge added to order independent of quantity e.g. "Reeling Fee"
         multiple: Multiple that the part is provided in
         minimum: MOQ (minimum order quantity) required for purchase
@@ -854,8 +853,6 @@ class SupplierPart(models.Model):
 
     note = models.CharField(max_length=100, blank=True, help_text='Notes')
 
-    single_price = models.DecimalField(max_digits=10, decimal_places=3, default=0, validators=[MinValueValidator(0)], help_text='Price for single quantity')
-
     base_cost = models.DecimalField(max_digits=10, decimal_places=3, default=0, validators=[MinValueValidator(0)], help_text='Minimum charge (e.g. stocking fee)')
 
     packaging = models.CharField(max_length=50, blank=True, help_text='Part packaging')
@@ -884,27 +881,26 @@ class SupplierPart(models.Model):
 
     def get_price(self, quantity, moq=True, multiples=True):
         """ Calculate the supplier price based on quantity price breaks.
-        
-        - If no price breaks available, use the single_price field
+
         - Don't forget to add in flat-fee cost (base_cost field)
         - If MOQ (minimum order quantity) is required, bump quantity
         - If order multiples are to be observed, then we need to calculate based on that, too
         """
 
-        # Order multiples
-        if multiples:
-            quantity = int(math.ceil(quantity / self.multipe) * self.multiple)
-
         # Minimum ordering requirement
         if moq and self.minimum > quantity:
             quantity = self.minimum
 
+        # Order multiples
+        if multiples:
+            quantity = int(math.ceil(quantity / self.multipe) * self.multiple)
+
         pb_found = False
         pb_quantity = -1
         pb_cost = 0.0
 
         for pb in self.price_breaks.all():
-            # Ignore this pricebreak!
+            # Ignore this pricebreak (quantity is too high)
             if pb.quantity > quantity:
                 continue
 
@@ -915,13 +911,11 @@ class SupplierPart(models.Model):
                 pb_quantity = pb.quantity
                 pb_cost = pb.cost
 
-        # No appropriate price-break found - use the single cost!
         if pb_found:
             cost = pb_cost * quantity
+            return cost + self.base_cost
         else:
-            cost = self.single_price * quantity
-
-        return cost + self.base_cost
+            return None
 
     def __str__(self):
         s = "{supplier} ({sku})".format(