diff --git a/Gemfile b/Gemfile
index 6285dab..84fd12d 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 source 'https://rubygems.org'
 
 require 'json'
diff --git a/Rakefile b/Rakefile
index 01734ae..360bfdf 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'html-proofer'
 require 'rspec/core/rake_task'
 
@@ -26,7 +27,7 @@ task :approved_licenses do
   puts approved.join(', ')
   puts "\n"
 
-  potential = approved - licenses.map { |l| l['id'] }
+  potential = approved - (licenses.map { |l| l['id'] })
   puts "#{potential.count} potential additions:"
   puts potential.join(', ')
 end
diff --git a/script/check-approval b/script/check-approval
index 2e4c9d2..6b491db 100755
--- a/script/check-approval
+++ b/script/check-approval
@@ -1,5 +1,6 @@
 #!/usr/bin/env ruby
 # frozen_string_literal: true
+
 # Checks if a given license meets the approval criteria to be added to choosealicense.com
 # See https://github.com/github/choosealicense.com/blob/gh-pages/CONTRIBUTING.md#adding-a-license
 # Usage: script/check-approval [SPDX LICENSE ID]
diff --git a/script/generate-docs b/script/generate-docs
index b4edae4..4940d69 100755
--- a/script/generate-docs
+++ b/script/generate-docs
@@ -1,5 +1,6 @@
 #!/usr/bin/env ruby
 # frozen_string_literal: true
+
 # Usage: script/generate-docs
 # Reads in the fields, meta, and rules YAML files and produces markdown output
 # suitable for documenting in the project's README
diff --git a/spec/ci_ruby_version_spec.rb b/spec/ci_ruby_version_spec.rb
index b61c7c5..6809848 100644
--- a/spec/ci_ruby_version_spec.rb
+++ b/spec/ci_ruby_version_spec.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'json'
 require 'open-uri'
 require 'spec_helper'
diff --git a/spec/license_bom_spec.rb b/spec/license_bom_spec.rb
index a3e2798..bed1d1e 100644
--- a/spec/license_bom_spec.rb
+++ b/spec/license_bom_spec.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'spec_helper'
 
 describe 'byte order marks' do
diff --git a/spec/license_fields_spec.rb b/spec/license_fields_spec.rb
index bac33e9..4215f37 100644
--- a/spec/license_fields_spec.rb
+++ b/spec/license_fields_spec.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'spec_helper'
 
 describe 'license fillable fields' do
@@ -6,7 +7,7 @@ describe 'license fillable fields' do
     context "The #{license['title']} license" do
       it 'should only contain supported fillable fields' do
         matches = license['content'].scan(/\[([a-z]+)\]/)
-        extra_fields = matches.flatten - fields.map { |f| f['name'] }
+        extra_fields = matches.flatten - (fields.map { |f| f['name'] })
         expect(extra_fields).to be_empty
       end
     end
diff --git a/spec/license_meta_spec.rb b/spec/license_meta_spec.rb
index 60ea68b..2e5b8c3 100644
--- a/spec/license_meta_spec.rb
+++ b/spec/license_meta_spec.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'spec_helper'
 
 describe 'license meta' do
@@ -8,7 +9,7 @@ describe 'license meta' do
 
     context "The #{license['title']} license" do
       it 'should only contain supported meta fields' do
-        extra_fields = raw_fields.keys - meta.map { |m| m['name'] }
+        extra_fields = raw_fields.keys - (meta.map { |m| m['name'] })
         expect(extra_fields).to be_empty
       end
 
diff --git a/spec/license_rules_spec.rb b/spec/license_rules_spec.rb
index 83137c2..450c164 100644
--- a/spec/license_rules_spec.rb
+++ b/spec/license_rules_spec.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'spec_helper'
 
 describe 'license rules' do
diff --git a/spec/license_shown_spec.rb b/spec/license_shown_spec.rb
index d2b50e4..4ef3f8c 100644
--- a/spec/license_shown_spec.rb
+++ b/spec/license_shown_spec.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'spec_helper'
 
 describe 'shown licenses' do
diff --git a/spec/license_spec.rb b/spec/license_spec.rb
index 95e6f43..0fd8a96 100644
--- a/spec/license_spec.rb
+++ b/spec/license_spec.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'spec_helper'
 
 describe 'licenses' do
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index c99daf6..ab89492 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'jekyll'
 require 'open-uri'
 require 'json'
@@ -42,7 +43,7 @@ def licenses
 end
 
 def shown_licenses
-  licenses.select { |l| !l['hidden'] }
+  licenses.reject { |l| l['hidden'] }
 end
 
 def site