Bundler Quiz!

(Translated from the Japanese article.)

This is a quiz about Ruby’s Bundler!

Add 8 characters to the following Gemfile so that bundle install fails (with non-zero exit code) for the second time or later.

source "https://rubygems.org"
gemspec

Notes:

• Bundler is a fairly recent version (approximately version 3 or later).
• The first invocation succeeds.

If you find the answer (on your own), please send me a direct message on ruby.social or email, etc.!

Wrong Answers

• An invalid URL like https://rubygems.org12345678: It doesn’t fail since Bundler doesn’t refer to the URL.
• An invalid URL and gems: It fails on the first run. It must fail only on the second or later runs.
• Something like this: It exeeds 8 characters.

  source "https://rubygems.org"
  gemspec
  File.file?("Gemfile.lock") and raise

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