Add Knapsack exercise

[fpsvogel]

Forum thread: https://forum.exercism.org/t/add-knapsack-exercise-48in24/10320

[kotp]

On Thu, Mar 14, 2024 at 10:21:35PM -0400, Felipe Vogel wrote: --- exercises/practice/knapsack/knapsack_test.rb | 97 ++++++++++++++++++++ 1 file changed, 97 insertions(+) diff --git a/exercises/practice/knapsack/knapsack_test.rb b/exercises/practice/knapsack/knapsack_test.rb index e69de29bb2..1a84e0e49f 100644 --- a/exercises/practice/knapsack/knapsack_test.rb +++ b/exercises/practice/knapsack/knapsack_test.rb @@ -0,0 +1,97 @@ +require 'minitest/autorun' +require_relative 'knapsack' + +class KnapsackTest < Minitest::Test + Item = Data.define(:weight, :value)

Loving the use of `Data` here.

+ + def test_no_items + # skip + max_weight = 100 + items = []

Consider making the assertion line have some kind of potential hint. In the case of the exercse "all your base" on Ruby, we do something like this: ```ruby assert_equal expected, converted, hint ``` In this case, we can do: ```ruby def test_no_items maximum_weight = 100 items = [] expected = 0 actual = Knapsack.new(maximum_weight).max_value(items) assert_equal expected, actual, 'For no items, the resulting value must be 0' ``` This can help layout the reading and provides a reason or a hint as to what you must do to make that test pass.

+ assert_equal 0, Knapsack.new(max_weight).max_value(items) + end +

---- ✂ Snip Snip ✂ ----

…

+ Item.new(weight: 118, value: 229), + Item.new(weight: 120, value: 240) + ] + assert_equal 1458, Knapsack.new(max_weight).max_value(items) + end +end

[kotp]

About the failing test, it is due to the Data use in the test, which I commented on as something I do like. But we should only use it if it is defined. This will require either a version check in the test with an alternative solution for that structure and the desired behavior, or a choice not to use Data in the test at all.

[kotp]

This will require either a version check in the test with an alternative solution for that structure and the desired behavior, or a choice not to use Data in the test at all.

Nah, just a conscious decision to bring it in even with the 3.1 version failing, for a known reason. This will pass on the platform, as it is using Ruby 3.3 according to the repository.

[fpsvogel]

@kotp Thanks for the feedback! I've made the changes that you suggested. Plus, I added punctuation and fixed typos in the explanation quoted from Reddit, in order to make it more readable.

[kotp]

Looking good, but a few changes are probably warranted in communicating what must be rather than what should be.