briancolfer

briancolfer

Agile Web Development with Rails 7: Iteration E2 the add_product method

The add_product method assumes that the default value for the quantity attribute is 0 when it is nil.

I think the code example for add_product:

	​def​ ​add_product​(product)
​ 	  current_item = line_items.​find_by​(​product_id: ​product.​id​)
​ 	  ​if​ current_item
​ 	    current_item.​quantity​ += 1
​ 	  ​else​
​ 	    current_item = line_items.​build​(​product_id: ​product.​id​)
​ 	  ​end​
​ 	  current_item
​ 	​end​

Should be:

  def add_product(product)
​    ​# replace multiple items for a single product in a cart with a​
​    # single item​
    current_item = line_items.find_by(product_id: product.id)
    if current_item
      if current_item.quantity.nil?
        current_item.quantity = 1
      else
        current_item.quantity += 1
      end
    else
      current_item = line_items.build(product_id: product.id, quantity: 1)
    end
    current_item
  end

Marked As Solved

briancolfer

briancolfer

I forgot the default value in the migration.

Where Next?

Popular Pragmatic Bookshelf topics Top

jimmykiang
This test is broken right out of the box… — FAIL: TestAgent (7.82s) agent_test.go:77: Error Trace: agent_test.go:77 agent_test.go:...
New
sdmoralesma
Title: Web Development with Clojure, Third Edition - migrations/create not working: p159 When I execute the command: user=> (create-...
New
joepstender
The generated iex result below should list products instead of product for the metadata. (page 67) iex> product = %Product{} %Pento....
New
cro
I am working on the “Your Turn” for chapter one and building out the restart button talked about on page 27. It recommends looking into ...
New
adamwoolhether
When trying to generate the protobuf .go file, I receive this error: Unknown flag: --go_opt libprotoc 3.12.3 MacOS 11.3.1 Googling ...
New
AndyDavis3416
@noelrappin Running the webpack dev server, I receive the following warning: ERROR in tsconfig.json TS18003: No inputs were found in c...
New
jskubick
I think I might have found a problem involving SwitchCompat, thumbTint, and trackTint. As entered, the SwitchCompat changes color to hol...
New
Charles
In general, the book isn’t yet updated for Phoenix version 1.6. On page 18 of the book, the authors indicate that an auto generated of ro...
New
jonmac
The allprojects block listed on page 245 produces the following error when syncing gradle: “org.gradle.api.GradleScriptException: A prob...
New
New

Other popular topics Top

AstonJ
A thread that every forum needs! Simply post a link to a track on YouTube (or SoundCloud or Vimeo amongst others!) on a separate line an...
New
AstonJ
If it’s a mechanical keyboard, which switches do you have? Would you recommend it? Why? What will your next keyboard be? Pics always w...
New
PragmaticBookshelf
Learn from the award-winning programming series that inspired the Elixir language, and go on a step-by-step journey through the most impo...
New
AstonJ
You might be thinking we should just ask who’s not using VSCode :joy: however there are some new additions in the space that might give V...
New
PragmaticBookshelf
From finance to artificial intelligence, genetic algorithms are a powerful tool with a wide array of applications. But you don't need an ...
New
AstonJ
I have seen the keycaps I want - they are due for a group-buy this week but won’t be delivered until October next year!!! :rofl: The Ser...
New
Margaret
Hello everyone! This thread is to tell you about what authors from The Pragmatic Bookshelf are writing on Medium.
1147 29994 760
New
AstonJ
We’ve talked about his book briefly here but it is quickly becoming obsolete - so he’s decided to create a series of 7 podcasts, the firs...
New
PragmaticBookshelf
Author Spotlight Mike Riley @mriley This month, we turn the spotlight on Mike Riley, author of Portable Python Projects. Mike’s book ...
New
AstonJ
Curious what kind of results others are getting, I think actually prefer the 7B model to the 32B model, not only is it faster but the qua...
New

Latest in Agile Web Development with Rails 7

Agile Web Development with Rails 7 Portal

Sub Categories: