[Fix #12695] Handle Include from inherited file in parent directory

When we inherit configuration from a file in a parent or ancestor
directory, and that file is called `.rubocop.yml`, the paths in
its Include parameters are interpreted as being relative to the
file, or rather its directory. This is specific for file names
starting with `.rubocop`. The problem is that file name matching
that we do when searching for target files to inspect doesn't work
for patterns that start with `..`. Solve the problem by matching
absolute paths in these corner cases.

changelog/fix_config_include_bug.md

@@ -0,0 +1 @@
+* [#12695](https://github.com/rubocop/rubocop/issues/12695): Fix bug in `Include` from inherited file in a parent directory. ([@jonas054][])

lib/rubocop/path_util.rb

@@ -44,14 +44,18 @@ def smart_path(path)
       end
     end
 
-    # rubocop:disable Metrics/MethodLength, Metrics/CyclomaticComplexity
+    # rubocop:disable Metrics/MethodLength, Metrics/CyclomaticComplexity, Metrics/PerceivedComplexity
     def match_path?(pattern, path)
       case pattern
       when String
         matches =
           if pattern == path
             true
           elsif glob?(pattern)
+            # File name matching doesn't really work with relative patterns the start with "..". We
+            # get around that problem by converting the pattern to an absolute path.
+            pattern = File.expand_path(pattern) if pattern.start_with?('..')
+
             File.fnmatch?(pattern, path, File::FNM_PATHNAME | File::FNM_EXTGLOB)
           end
 
@@ -66,7 +70,7 @@ def match_path?(pattern, path)
         end
       end
     end
-    # rubocop:enable Metrics/MethodLength, Metrics/CyclomaticComplexity
+    # rubocop:enable Metrics/MethodLength, Metrics/CyclomaticComplexity, Metrics/PerceivedComplexity
 
     # Returns true for an absolute Unix or Windows path.
     def absolute?(path)

spec/rubocop/cli_spec.rb

@@ -1113,6 +1113,31 @@ def meow_at_4am?
                                                     abs('regexp')])
     end
 
+    context 'when a .rubocop.yml is included from an ancestor directory' do
+      before do
+        create_file('child/grandkid/.rubocop.yml', <<~YAML)
+          inherit_from:
+            - ../../.rubocop.yml
+        YAML
+      end
+
+      context 'and it specifies an Include pattern' do
+        before do
+          create_file('.rubocop.yml', <<~YAML)
+            AllCops:
+              Include:
+                - "**/*.rbi"
+          YAML
+        end
+
+        it 'finds files included through inheritance' do
+          create_file('child/grandkid/file.rbi', 'x=0')
+          Dir.chdir('child/grandkid') { expect(cli.run(['-L'])).to eq(0) }
+          expect($stdout.string).to eq("file.rbi\n")
+        end
+      end
+    end
+
     it 'ignores excluded files' do
       create_file('example.rb', ['x = 0', 'puts x'])
       create_file('regexp.rb', ['x = 0', 'puts x'])