Check if multiple key-value pairs exist in a Ruby hash?-CodePudding

I have the following Ruby hash key-value pairs:

[
   {
      "trait_type"=>"Status", 
      "value"=>"Unbuilt", 
      "display_type"=>nil, 
      "max_value"=>nil, 
      "trait_count"=>4866, 
      "order"=>nil
   }
]

What I need to check is see if the following key-value pairs are both present:

{
   "value"=>"Unbuilt", 
   "trait_type"=>"Status"
}

Essentially wanting something to the effect of...

traits = [{"trait_type"=>"Status", "value"=>"Unbuilt", "display_type"=>nil, "max_value"=>nil, "trait_count"=>4866, "order"=>nil}]
filter_traits = {"value"=>"Unbuilt", "trait_type"=>"Status"}

traits.include? filter_traits

CodePudding user response：

If you are using ruby >= 2.3, there is a fancy new Hash >= Hash operation that is conceptually similiar to a hypothetical contains?

Using your traits array:

trait = traits[0]
trait >= {"trait_type" => "Status", "value" => "Unbuilt"}
# => true

trait >= {"trait_type" => "Status", "value" => "Built"}
# => false

So you could try something like:

traits.select{|trait|
  trait >= filter_traits
}.length > 0
# => true

CodePudding user response：

We have the aptly named all? and any? methods that should do exactly what you're looking for.

All we need to do is loop through your filter_traits hash and test to see if all (or any) those key:value pairs are equal to (==) any corresponding key:value pairs inside your traits array:

traits = [{"trait_type"=>"Status", "value"=>"Unbuilt", "display_type"=>nil, "max_value"=>nil, "trait_count"=>4866, "order"=>nil}]
filter_traits = {"value"=>"Unbuilt", "trait_type"=>"Status"}

filter_traits.all? {|k, v| filter_traits[k] == traits[0][k]}
#=>  true

filter_traits = {"value"=>"Built", "trait_type"=>"Status"}
filter_traits.all? {|k, v| filter_traits[k] == traits[0][k]}
#=>  false

filter_traits.any? {|k, v| filter_traits[k] == traits[0][k]}
#=>  true