How to select for multiple conditions to return one object that matches those conditions

I am creating a test, and am trying to create a method that pulls a specific job posting ID when it matches the job posting title, the job type and the description, just in case that the case that there are more than one job posting with the same title.

I cannot get the select statement to pull the job posting ID out of the instance variable. Debugging shows that there is indeed the ID nested in the instance variable, but my conditions aren't being met because I am not doing it correctly.

@job_posting is the instance variable that contains the ID that I need, but I need my parameters in select to match so I can subsequently return the ID.

whenever I ONLY use posting title,such as:

target_postings = @job_postings.select{|posting|posting[:posting_title]}

it works and returns the ID I need, however I cannot do this:

def get_specific_posting_id_for_posting(posting_title, job_type, description)
  expect(@job_postings.length > 0)
  target_postings = @job_postings.select {|posting| posting[:posting_title] == posting_title; posting[:job_type] == job_type; posting[:description] == description}
  expect(target_postings.length == 1)
  target_posting = target_postings[0]
  posting_id = target_posting[:posting_id]
  posting_id
end

It looks like

target_postings = @job_postings.select {|posting| posting[:posting_title] == posting_title; posting[:job_type] == job_type; posting[:description] == description}

should probably be

target_postings = @job_postings.select do |posting| 
  posting[:posting_title] == posting_title 
    && posting[:job_type] == job_type 
    && posting[:description] == description
end

Your version has three separate checks, the first two of which do nothing, only the last statement in the block is actually being used to determine whether the item matches.

As an aside, since it looks like you only want the single first element that matches your conditions, you might want to consider using find instead of select. It works the same except it will stop iterating and return as soon as it finds the first matching item.