Added Cop for injecting EE modules

This Cop enforces the rule that injecting EE modules (using prepend,
include, or extend) is done by placing the injection on the last line of
a file, instead of somewhere in the middle. By placing these lines at
the very end, merge conflicts will not happen.

1 files changed, 133 insertions, 0 deletions

diff --git a/spec/rubocop/cop/inject_enterprise_edition_module_spec.rb b/spec/rubocop/cop/inject_enterprise_edition_module_spec.rb
new file mode 100644
index 00000000000..08ffc3c3a53
--- /dev/null
+++ b/spec/rubocop/cop/inject_enterprise_edition_module_spec.rb
@@ -0,0 +1,133 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+require 'rubocop'
+require 'rubocop/rspec/support'
+require_relative '../../../rubocop/cop/inject_enterprise_edition_module'
+
+describe RuboCop::Cop::InjectEnterpriseEditionModule do
+  include CopHelper
+
+  subject(:cop) { described_class.new }
+
+  it 'flags the use of `prepend EE` in the middle of a file' do
+    expect_offense(<<~SOURCE)
+    class Foo
+      prepend EE::Foo
+      ^^^^^^^^^^^^^^^ Injecting EE modules must be done on the last line of this file, outside of any class or module definitions
+    end
+    SOURCE
+  end
+
+  it 'flags the use of `prepend ::EE` in the middle of a file' do
+    expect_offense(<<~SOURCE)
+    class Foo
+      prepend ::EE::Foo
+      ^^^^^^^^^^^^^^^^^ Injecting EE modules must be done on the last line of this file, outside of any class or module definitions
+    end
+    SOURCE
+  end
+
+  it 'flags the use of `include EE` in the middle of a file' do
+    expect_offense(<<~SOURCE)
+    class Foo
+      include EE::Foo
+      ^^^^^^^^^^^^^^^ Injecting EE modules must be done on the last line of this file, outside of any class or module definitions
+    end
+    SOURCE
+  end
+
+  it 'flags the use of `include ::EE` in the middle of a file' do
+    expect_offense(<<~SOURCE)
+    class Foo
+      include ::EE::Foo
+      ^^^^^^^^^^^^^^^^^ Injecting EE modules must be done on the last line of this file, outside of any class or module definitions
+    end
+    SOURCE
+  end
+
+  it 'flags the use of `extend EE` in the middle of a file' do
+    expect_offense(<<~SOURCE)
+    class Foo
+      extend EE::Foo
+      ^^^^^^^^^^^^^^ Injecting EE modules must be done on the last line of this file, outside of any class or module definitions
+    end
+    SOURCE
+  end
+
+  it 'flags the use of `extend ::EE` in the middle of a file' do
+    expect_offense(<<~SOURCE)
+    class Foo
+      extend ::EE::Foo
+      ^^^^^^^^^^^^^^^^ Injecting EE modules must be done on the last line of this file, outside of any class or module definitions
+    end
+    SOURCE
+  end
+
+  it 'does not flag prepending of regular modules' do
+    expect_no_offenses(<<~SOURCE)
+    class Foo
+      prepend Foo
+    end
+    SOURCE
+  end
+
+  it 'does not flag including of regular modules' do
+    expect_no_offenses(<<~SOURCE)
+    class Foo
+      include Foo
+    end
+    SOURCE
+  end
+
+  it 'does not flag extending using regular modules' do
+    expect_no_offenses(<<~SOURCE)
+    class Foo
+      extend Foo
+    end
+    SOURCE
+  end
+
+  it 'does not flag the use of `prepend EE` on the last line' do
+    expect_no_offenses(<<~SOURCE)
+    class Foo
+    end
+
+    Foo.prepend(EE::Foo)
+    SOURCE
+  end
+
+  it 'does not flag the use of `include EE` on the last line' do
+    expect_no_offenses(<<~SOURCE)
+    class Foo
+    end
+
+    Foo.include(EE::Foo)
+    SOURCE
+  end
+
+  it 'does not flag the use of `extend EE` on the last line' do
+    expect_no_offenses(<<~SOURCE)
+    class Foo
+    end
+
+    Foo.extend(EE::Foo)
+    SOURCE
+  end
+
+  it 'autocorrects offenses by just disabling the Cop' do
+    source = <<~SOURCE
+    class Foo
+      prepend EE::Foo
+      include Bar
+    end
+    SOURCE
+
+    expect(autocorrect_source(source)).to eq(<<~SOURCE)
+    class Foo
+      prepend EE::Foo # rubocop: disable Cop/InjectEnterpriseEditionModule
+      include Bar
+    end
+    SOURCE
+  end
+end