Twig loop and building hash - symfony

Question

i have a problem with twig syntax and merge function ... I have multiple object with 2 field category and price.
I need to create an array or hash (i guess hash is easier but ... i try both) with sum of prices for each category.
So i try many code, and my last is :
{% set test = [ {'category': 'description', 'price': '1'}, { 'category': 'abc', 'price': '2'}, { 'category':'description', 'price': '3'} ] %}
{% set listCategory={} %}
{% for line in test %}
{% set new_category = { 'category': line.category, 'price': line.price } %}
{% if loop.first %}
{% set listCategory = listCategory|merge([new_category]) %}
{% else %}
{% set flag = false %}
{% for category in listCategory %}
{% if line['category'] == new_category['category'] %}
{% set tmp = line['price'] + new_category['price'] %}
{# i try it too#}
{% set category = category|merge([tmp]) %}
{# or i try this#}
{% set category = category|merge({ (category.price) : category.price + new_category.price }) %}
{{ dump(listCategory) }}
{% endif %}
{% endfor %}
{% endif %}
{% endfor %}
I try it since 3 hours and i don't know where i make an error.
When i check my array, i test if the key 'name' exist
if yes, i want to add the price of element to the hash price
if no, i want to add a new array in hash with key = 'name'
Anyone have an idea ? thx for your reading.

Answer 1

I think you are looking for something similar to:
{% set test = [ {'category': 'description', 'price': 1}, { 'category': 'abc', 'price': 2}, { 'category':'description', 'price': 3} ] %}
{% set listCategory={} %}
{% for line in test %}
{% set key = line.category %}
{% if listCategory[key] is defined %}
{# notice here that the key is in brackets () because otherwise it will be interpreted as the string "key" %}
{% set listCategory = listCategory|merge({(key):listCategory[line.category]+line.price}) %}
{% else %}
{% set listCategory = listCategory|merge({(key):line.price}) %}
{% endif %}
{{ key }}: {{ listCategory[key] }}
{% endfor %}