Always expand indexables' full paths (#1977)

Depends on the `included_pattern`'s value, `Dir.glob` may return relative
paths as its default base is the current working directory. For example,
if the `included_pattern` is `**/*.rb`, the `Dir.glob` will return
relative paths like `lib/foo.rb` instead of the full path like
`/path/to/project/lib/foo.rb`.

This commit ensures that the full paths are always expanded by using
`File.expand_path` on the paths returned by `Dir.glob`.

Fixes #1971

lib/ruby_indexer/lib/ruby_indexer/configuration.rb

@@ -56,6 +56,7 @@ def indexables
         load_path_entry = T.let(nil, T.nilable(String))
 
         Dir.glob(pattern, File::FNM_PATHNAME | File::FNM_EXTGLOB).map! do |path|
+          path = File.expand_path(path)
           # All entries for the same pattern match the same $LOAD_PATH entry. Since searching the $LOAD_PATH for every
           # entry is expensive, we memoize it until we find a path that doesn't belong to that $LOAD_PATH. This happens
           # on repositories that define multiple gems, like Rails. All frameworks are defined inside the Dir.pwd, but

lib/ruby_indexer/test/configuration_test.rb

@@ -20,6 +20,14 @@ def test_load_configuration_executes_configure_block
       assert(indexables.none? { |indexable| indexable.full_path == __FILE__ })
     end
 
+    def test_indexables_have_expanded_full_paths
+      @config.apply_config({ "included_patterns" => ["**/*.rb"] })
+      indexables = @config.indexables
+
+      # All paths should be expanded
+      assert(indexables.none? { |indexable| indexable.full_path.start_with?("lib/") })
+    end
+
     def test_indexables_only_includes_gem_require_paths
       indexables = @config.indexables