Fix isolated test files should not break isolation.

martinemde · bbatsov · commit 3d427bb323b5 · 2023-09-10T09:44:24.000+02:00
Ensures that files created during isolated tests do not get added
outside of the isolated directory tree.

This prevents tests from being created in a way that relies on the test
infrastructure to pass that would not pass in a real world scenario.
diff --git a/spec/rubocop/cop/team_spec.rb b/spec/rubocop/cop/team_spec.rb
@@ -88,7 +88,7 @@ def a
   describe '#inspect_file', :isolated_environment do
     include FileHelper
 
-    let(:file_path) { '/tmp/example.rb' }
+    let(:file_path) { 'example.rb' }
     let(:source) do
       source = RuboCop::ProcessedSource.from_file(file_path, ruby_version)
       source.config = config
@@ -175,7 +175,7 @@ def a
 
       let(:error_message) do
         'An error occurred while Style/NumericLiterals cop was inspecting ' \
-          '/tmp/example.rb:1:0.'
+          'example.rb:1:0.'
       end
 
       it 'records Team#errors' do
@@ -198,7 +198,7 @@ def a
         RUBY
       end
 
-      let(:file_path) { '/tmp/Gemfile' }
+      let(:file_path) { 'Gemfile' }
 
       let(:buggy_correction) { ->(_corrector) do raise cause end }
       let(:options) { { autocorrect: true } }
@@ -207,7 +207,7 @@ def a
 
       let(:error_message) do
         'An error occurred while Bundler/OrderedGems cop was inspecting ' \
-          '/tmp/Gemfile.'
+          'Gemfile.'
       end
 
       it 'records Team#errors' do
diff --git a/spec/rubocop/target_finder_spec.rb b/spec/rubocop/target_finder_spec.rb
@@ -510,18 +510,16 @@
     end
 
     it 'can exclude symlinks as well as directories' do
-      Dir.mktmpdir do |tmpdir|
-        create_empty_file(File.join(tmpdir, 'ruby5.rb'))
-        create_link('link', tmpdir)
+      create_empty_file(File.join(Dir.home, 'ruby5.rb'))
+      create_link('link', Dir.home)
 
-        config = instance_double(RuboCop::Config)
-        exclude_property = { 'Exclude' => [File.expand_path('link/**/*')] }
-        allow(config).to receive(:for_all_cops).and_return(exclude_property)
-        allow(config_store).to receive(:for).and_return(config)
+      config = instance_double(RuboCop::Config)
+      exclude_property = { 'Exclude' => [File.expand_path('link/**/*')] }
+      allow(config).to receive(:for_all_cops).and_return(exclude_property)
+      allow(config_store).to receive(:for).and_return(config)
 
-        expect(found_basenames.include?('ruby5.rb')).to be(false)
-        expect(found_basenames.include?('ruby3.rb')).to be(true)
-      end
+      expect(found_basenames.include?('ruby5.rb')).to be(false)
+      expect(found_basenames.include?('ruby3.rb')).to be(true)
     end
   end
 
diff --git a/spec/support/file_helper.rb b/spec/support/file_helper.rb
@@ -6,6 +6,8 @@ module FileHelper
   def create_file(file_path, content)
     file_path = File.expand_path(file_path)
 
+    ensure_descendant(file_path)
+
     dir_path = File.dirname(file_path)
     FileUtils.mkdir_p dir_path
 
@@ -30,9 +32,18 @@ def create_empty_file(file_path)
   def create_link(link_path, target_path)
     link_path = File.expand_path(link_path)
 
+    ensure_descendant(link_path)
+
     dir_path = File.dirname(link_path)
     FileUtils.mkdir_p dir_path
 
     FileUtils.symlink(target_path, link_path)
   end
+
+  def ensure_descendant(path, base = RuboCop::FileFinder.root_level)
+    return unless base
+    return if path.start_with?(base) && path != base
+
+    raise "Test file #{path} is outside of isolated_environment root #{base}"
+  end
 end
