feat!: Implement blank_gem that does nothing.

blank_gem.gemspec

@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+require_relative 'lib/blank_gem/version'
+
+Gem::Specification.new do |spec|
+  spec.name = 'blank_gem'
+  spec.version = BlankGem::VERSION
+  spec.authors = ['Jim Myhrberg']
+  spec.email = ['contact@jimeh.me']
+
+  spec.summary = 'A blank/empty Ruby gem that does nothing.'
+  spec.description = 'A blank/empty Ruby gem that does nothing. Useful for ' \
+                     'testing that only specific Bundler groups are loaded ' \
+                     'when using a dummy group.'
+  spec.homepage = 'https://github.com/jimeh/blank_gem'
+  spec.required_ruby_version = Gem::Requirement.new('>= 2.0.0')
+
+  spec.metadata['homepage_uri'] = spec.homepage
+  spec.metadata['source_code_uri'] = spec.homepage
+  spec.metadata['changelog_uri'] = spec.homepage
+
+  spec.files = Dir.glob('lib/**/*') + [
+    'Gemfile',
+    'LICENSE',
+    'README.md',
+    'Rakefile',
+    'VERSION'
+  ]
+  spec.bindir = 'exe'
+  spec.executables = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
+  spec.require_paths = ['lib']
+end