BOM variant calculating absurd quantities for "Materials Required (Exploded)". Weird!

MartinHBramwell · May 2, 2021, 11:59pm

I have created a BOM for a chemical that we require to have in two concentrations: 2000ppm and 4000ppm.

The template BOM looks like this:

BOM2

I use the “Create” button to start a variant BOM and upon saving get this:

BOM-2k2

In the “Materials Required” section the sum of the quantities of the 4 items is 1.013650.

That number is then used as the percentage increase to the exploded quantities…

… or in other words: each exploded item quantity is the original quantity multiplied by the sum of all the original quantities. What?

Please, someone, help me understand :

Is that a bug?
Have I made a mistake?
If it is correct, how does it make any sense at all?

erpnext 13.0.2
frappe 13.0.3

casesolved-co-uk · July 4, 2021, 10:57am

Just found this also on a customer implementation. Shows just how little new features get tested!

Documented and fixed here:

github.com/frappe/erpnext

bug: BOM variant creation inserts wrong child links

opened 08:28AM - 02 Jul 21 UTC

closed 05:29AM - 05 Jul 21 UTC

nameduser0

bug valid

## Description of the issue On creation of variant BOMs from template BOMs, ERP…Next is linking the parent BOM of a component as a child. This completely breaks all the costing, work orders and job cards. Template BOM: ![BOM Template](https://user-images.githubusercontent.com/64409021/124244116-814cf580-db16-11eb-9f73-7f29d799c264.png) Variant BOM: ![BOM Variant Error](https://user-images.githubusercontent.com/64409021/124244134-85791300-db16-11eb-827e-33e57fc3cc9e.png) ## Context information (for bug reports) **Output of `bench version`** ``` ERPNext: v13.5.0 (version-13) Frappe Framework: v13.5.1 (version-13) ``` ## Steps to reproduce the issue 1. Create template and variant items of product plus components 2. Create template BOM 3. Use menu to create variant BOMs ### Observed result See screenshots above ### Expected result No unnecessary nesting, structure should match the template

Let me know if you want to know how to fix your database.

MartinHBramwell · July 4, 2021, 11:54am

Thanks for looking at that.

This crap caused me a huge embarrassment in front of the whole company. As in, “There are so many ERP alternatives out there. Wouldn’t it have been better if you had picked one that actually works?”

casesolved-co-uk · July 4, 2021, 2:58pm

Strip duly torn:

[fix: incorrect bom no. added for non-variant items on variant boms by nameduser0 · Pull Request #26320 · frappe/erpnext · GitHub](Comment link)

MartinHBramwell · July 4, 2021, 3:22pm

Hear! Hear!

I started with ERPNext 18 months ago with high hopes and goals. After stumbling from one minefield to another during that time, I am terrified of trying to add anything new to what we are currently doing.

casesolved-co-uk · July 4, 2021, 5:15pm

Set up a test site/bench/instance, restore a backup and try it out first! bench and instance options are good if you’re thinking of upgrading.

MartinHBramwell · July 4, 2021, 5:24pm

Oh yeah! I always do that!

I’m not so much afraid I’ll hand over bad code to users. Mostly, they don’t see what I haven’t tried myself, unless there’s a regression somewhere.

I am afraid of losing yet another week out of my life for each and every new [ AttributeError: 'NoneType' object has no attribute ... ] mystery or whatever "Oh gee, it seems we don’t have a test for that" that’s lurking in the bowels of what I need to do.