StockItemCreate form now has better logic for auto-detecting the part

InvenTree/stock/views.py

@@ -1036,6 +1036,37 @@ class StockItemCreate(AjaxCreateView):
     ajax_template_name = 'modal_form.html'
     ajax_form_title = _('Create new Stock Item')
 
+    def get_part(self, form=None):
+        """
+        Attempt to get the "part" associted with this new stockitem.
+
+        - May be passed to the form as a query parameter (e.g. ?part=<id>)
+        - May be passed via the form field itself.
+        """
+
+        # Try to extract from the URL query
+        part_id = self.request.GET.get('part', None)
+
+        if part_id:
+            try:
+                part = Part.objects.get(pk=part_id)
+                return part
+            except (Part.DoesNotExist, ValueError):
+                pass
+
+        # Try to get from the form
+        if form:
+            try:
+                part_id = form['part'].value()
+                part = Part.objects.get(pk=part_id)
+                return part
+            except (Part.DoesNotExist, ValueError):
+                pass
+
+        # Could not extract a part object
+        return None
+
+
     def get_form(self):
         """ Get form for StockItem creation.
         Overrides the default get_form() method to intelligently limit
@@ -1044,18 +1075,14 @@ class StockItemCreate(AjaxCreateView):
 
         form = super().get_form()
 
-        part = None
-
-        # If the user has selected a Part, limit choices for SupplierPart
-        if form['part'].value():
-            part_id = form['part'].value()
-
-            try:
-                part = Part.objects.get(id=part_id)
+        part = self.get_part(form=form)
 
+        if part is not None:
             sn = part.getNextSerialNumber()
             form.field_placeholder['serial_numbers'] = _('Next available serial number is') + ' ' + str(sn)
 
+            print("Placeholder:", sn)
+
             form.rebuild_layout()
 
             # Hide the 'part' field (as a valid part is selected)
@@ -1086,11 +1113,8 @@ class StockItemCreate(AjaxCreateView):
                     # TODO - This does NOT work for some reason? Ref build.views.BuildItemCreate
                     form.fields['supplier_part'].initial = all_parts[0].id
 
-            except Part.DoesNotExist:
-                pass
-
         # Otherwise if the user has selected a SupplierPart, we know what Part they meant!
-        elif form['supplier_part'].value() is not None:
+        if form['supplier_part'].value() is not None:
             pass
             
         return form
@@ -1113,28 +1137,21 @@ class StockItemCreate(AjaxCreateView):
         else:
             initials = super(StockItemCreate, self).get_initial().copy()
 
-        part_id = self.request.GET.get('part', None)
+        part = self.get_part()
+
         loc_id = self.request.GET.get('location', None)
         sup_part_id = self.request.GET.get('supplier_part', None)
 
-        part = None
         location = None
         supplier_part = None
 
-        # Part field has been specified
-        if part_id:
-            try:
-                part = Part.objects.get(pk=part_id)
-
+        if part is not None:
             # Check that the supplied part is 'valid'
             if not part.is_template and part.active and not part.virtual:
                 initials['part'] = part
                 initials['location'] = part.get_default_location()
                 initials['supplier_part'] = part.default_supplier
 
-            except (ValueError, Part.DoesNotExist):
-                pass
-
         # SupplierPart field has been specified
         # It must match the Part, if that has been supplied
         if sup_part_id: