issue-link js-issue-link" data-error-text="Failed to load title" data-id="2070986471" data-permission-text="Title is private" data-url="https://github.com/rubocop/rubocop/issues/12600" data-hovercard-type="issue" data-hovercard-url="/rubocop/rubocop/issues/12600/hovercard" href="https://github.com/rubocop/rubocop/issues/12600">rubocop/rubocop#12600. ## Configuration By default, analysis is performed using the Parser gem, so the default value for the newly added `parser_engine` is `parser_whitequark`: ```ruby ProcessedSource.new(@options[:stdin], ruby_version, file, parser_engine: :parser_whitequark) ``` This code maintains compatibility, meaning the traditional behavior is preserved: ```ruby ProcessedSource.new(@options[:stdin], ruby_version, file) ``` To perform analysis using Prism, specify `parser_engine: :parser_prism`: ```ruby ProcessedSource.new(@options[:stdin], ruby_version, file, parser_engine: :parser_prism) ``` The parameter name `parser_prism` reflects the original parser_prism which was the basis for `Prism::Translation::Parser` (now integrated into Prism): https://github.com/kddnewton/parser-prism This is an experimental introduction, and some incompatibilities still remain. > [!NOTE] > As initially mentioned in rubocop/rubocop#12600 (comment), > the plan was to set `parser_engine: prism`. > > However, the parser engine used in this PR is `Prism::Translation::Parser`, not `Prism`: > ruby/prism#2419 > > `Prism::Translation::Parser` and `Prism` have different ASTs, so their migration will definitely cause incompatibility. > So, considering the possibility of further replacing `Prism::Translation::Parser` with `Prism` in the future, > it has been decided that it might be better not to use `ParserEngine: prism` for the time being. > `ParserEngine: prism` is reserved for `Prism`, not `Prism::Translation::Parser`. > > Therefore, the parameter value has been set to `parser_engine: parser_prism` specifically for > `Prism::Translation::Parser`. > > This means that the planned way to specify Prism in .rubocop.yml file will be `ParserEngine: parser_prism`, > not `ParserEngine: prism`. ## Compatibility The compatibility issues between Prism and the Parser gem have not been resolved. The failing tests will be skipped with `broken_on: :prism`: - ruby/prism#2454 has been resolved but not yet released. - ruby/prism#2467 is still unresolved. Issues that will be resolved in several upcoming releases of Prism are being skipped with `broken_on: :prism`. Anyway, RuboCop AST can be released independently of the resolution and release of Prism. > [!NOTE] > The hack in `Prism::Translation::Parser` for `ProcessedSource` needs to be fixed: > https://github.com/ruby/prism/blob/v0.24.0/lib/prism/translation/parser/rubocop.rb > > If the above interface is accepted, a fix will be proposed on the Prism side. ## Test Tests for RuboCop AST with Prism as the backend can be run as follows: ```console bundle exec rake prism_spec ``` The above is the shortcut alias for: ```console PARSER_ENGINE=parser_prism TARGET_RUBY_VERSION=3.3 rake spec ``` RuboCop AST works on Ruby versions 2.6+, but since Prism only targets analysis for Ruby 3.3+, `internal_investigation` Rake task will not be executed. This task is only run with the Parser gem, which can analyze Ruby versions 2.0+.

Commits

Commits on Feb 25, 2024

Support Prism as a Ruby parser