Heroku could not detect rake tasks (LoadError: cannot load such file -- rspec/core/rake_task)

Question

I'm using travisCI to deploy to heroku and I am getting this error. It has only just started happening.

I have the basic rails Rakefile and I have a file that looks like this as otherwise travis cannot detect the rake tasks:

# lib\tasks\spec.rake
require 'rspec/core/rake_task'
RSpec::Core::RakeTask.new
task :default => :spec

Why would this error be displaying specifically for heroku?

EDIT - I had a similar version to the (better) answer given:

begin
  require 'rspec/core/rake_task'
  desc "Run all examples"
  RSpec::Core::RakeTask.new(:spec) do |t|
    t.rspec_opts = %w[--color]
    t.pattern = 'spec/*_spec.rb'
  end
 rescue LoadError
end

@FrederickCheung it's just in the development group. Would this be the issue? — Koxzi, Apr 19 '15 at 18:14

score 11 · Accepted Answer · answered Apr 19 '15 at 18:17

11

If rspec isn't in the production group (it generally isn't) then the code you posted would fail when run in a production environment like heroku.

In the rspec docs they recommend doing this:

begin
  require 'rspec/core/rake_task'
  RSpec::Core::RakeTask.new(:spec)
rescue LoadError
end

So that the absence of rspec doesn't stop your rakefile loading.

answered Apr 19 '15 at 18:17

Frederick Cheung

83,189
8
152
174

Oh right. I had a slightly more complex version but commented out. I've added it to the post for reference. – Koxzi Apr 19 '15 at 18:24

score 2 · Answer 2 · answered Jul 18 '19 at 07:34

2

FWIW, I just faced the same issue. I fixed it by moving rspec-rails to production as shown below. I don't know why it works, but it works for me.

group :production, :development, :test do
  gem 'rspec-rails', '~> 3.8'
end

answered Jul 18 '19 at 07:34

suretrust

31
2

1

is it a good idea to put rspec-rails to production? – Adem Dinarević Dec 12 '20 at 17:47

Heroku could not detect rake tasks (LoadError: cannot load such file -- rspec/core/rake_task)

2 Answers2

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