Use relative path to match with glob

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## Master (Unreleased)
 
+* Fix `RSpec/FilePath` detection when absolute path includes test subject. ([@eitoball][])
+
 ## 1.38.1 (2020-02-15)
 
 * Fix `RSpec/RepeatedDescription` to detect descriptions with interpolation and methods. ([@lazycoder9][])
@@ -489,3 +491,4 @@ Compatibility release so users can upgrade RuboCop to 0.51.0. No new features.
 [@dduugg]: https://github.com/dduugg
 [@lazycoder9]: https://github.com/lazycoder9
 [@elebow]: https://github.com/elebow
+[@eitoball]: https://github.com/eitoball

lib/rubocop/cop/rspec/file_path.rb

@@ -103,7 +103,9 @@ def ignore_methods?
         end
 
         def filename_ends_with?(glob)
-          File.fnmatch?("*#{glob}", processed_source.buffer.name)
+          filename =
+            RuboCop::PathUtil.relative_path(processed_source.buffer.name)
+          File.fnmatch?("*#{glob}", filename)
         end
 
         def relevant_rubocop_rspec_file?(_file)

spec/rubocop/cop/rspec/file_path_spec.rb

@@ -172,6 +172,15 @@
     RUBY
   end
 
+  it 'uses relative path' do
+    allow(RuboCop::PathUtil)
+      .to receive(:relative_path).and_return('spec/models/bar_spec.rb')
+    expect_offense(<<-RUBY, '/home/foo/spec/models/bar_spec.rb')
+      describe Foo do; end
+      ^^^^^^^^^^^^ Spec path should end with `foo*_spec.rb`.
+    RUBY
+  end
+
   context 'when configured with CustomTransform' do
     let(:cop_config) { { 'CustomTransform' => { 'FooFoo' => 'foofoo' } } }