Deprecate TargetRubyVersion: 80_82_73_83_77.xx

Prism has been directly supported as a parser engine since RuboCop 1.62:
https://github.com/rubocop/rubocop/releases/tag/v1.62.0

This makes specifying `TargetRubyVersion` with special values like `80_82_73_83_77.33`
using the `prism/translation/parser/rubocop` file unnecessary.
As a result, it would be possible to deprecate this approach.

OTOH, early users might be surprised if `prism/translation/parser/rubocop` were to be suddenly removed.
Therefore, this PR deprecates the parameters related to `prism/translation/parser/rubocop`.

```console
$ bundle exec ruby -rrubocop -rprism/translation/parser/rubocop -e "RuboCop::AST::ProcessedSource.new('42', 80_82_73_83_77.33).ast"
WARN: Prism is directly supported since RuboCop 1.62. The `prism/translation/parser/rubocop` file is deprecated.
WARN: Setting `TargetRubyVersion: 80_82_73_83_77.33` is deprecated. Set to `ParserEngine: parser_prism` and `TargetRubyVersion: 3.3` instead.

$ bundle exec ruby -rrubocop -rprism/translation/parser/rubocop -e "RuboCop::AST::ProcessedSource.new('42', 80_82_73_83_77.34).ast"
WARN: Prism is directly supported since RuboCop 1.62. The `prism/translation/parser/rubocop` file is deprecated.
WARN: Setting `TargetRubyVersion: 80_82_73_83_77.34` is deprecated. Set to `ParserEngine: parser_prism` and `TargetRubyVersion: 3.4` instead.
```

Eventually, it will be possible to remove it at some point.

Regarding documentation, it has been updated to not show the old, discouraged usage but rather
the new way of specifying it in RuboCop.

docs/parser_translation.md

@@ -16,19 +16,24 @@ Prism::Translation::Parser.parse_file("path/to/file.rb")
 
 ### RuboCop
 
-To run RuboCop using the `prism` gem as the parser, you will need to require the `prism/translation/parser/rubocop` file. This file injects `prism` into the known options for both `rubocop` and `rubocop-ast`, such that you can specify it in your `.rubocop.yml` file. Unfortunately `rubocop` doesn't support any direct way to do this, so we have to get a bit hacky.
+Prism as a parser engine is directly supported since RuboCop 1.62. The class used for parsing is `Prism::Translation::Parser`.
 
-First, set the `TargetRubyVersion` in your RuboCop configuration file to `80_82_73_83_77.33`. This is the version of Ruby that `prism` reports itself as. (The leading numbers are the ASCII values for `PRISM`.)
+First, specify `prism` in your Gemfile:
 
-```yaml
-AllCops:
-  TargetRubyVersion: 80_82_73_83_77.33
+```ruby
+gem "prism"
 ```
 
-Now when you run `rubocop` you will need to require the `prism/translation/parser/rubocop` file before executing so that it can inject the `prism` parser into the known options.
+To use Prism with RuboCop, specify `ParserEngine` and `TargetRubyVersion` in your RuboCop configuration file:
 
+```yaml
+AllCops:
+  ParserEngine: parser_prism
+  TargetRubyVersion: 3.3
 ```
-bundle exec ruby -rprism/translation/parser/rubocop $(bundle exec which rubocop)
-```
 
-This should run RuboCop using the `prism` parser.
+The default value for `ParserEngine` is `parser_whitequark`, which indicates the Parser gem. You need to explicitly switch it to `parser_prism` to indicate Prism. Additionally, the value for `TargetRubyVersion` must be specified as `3.3` or higher, as Prism supports parsing versions of Ruby 3.3 and higher.
+The parser class is determined by the combination of values for `ParserEngine` and `TargetRubyVersion`. For example, if `TargetRubyVersion: 3.3`, parsing is performed by `Prism::Translation::Parser33`, and for `TargetRubyVersion 3.4`, parsing is performed by `Prism::Translation::Parser34`.
+
+For further information, please refer to the RuboCop documentation:
+https://docs.rubocop.org/rubocop/configuration.html#setting-the-parser-engine

lib/prism/translation/parser/rubocop.rb

@@ -1,6 +1,8 @@
 # frozen_string_literal: true
 # typed: ignore
 
+warn "WARN: Prism is directly supported since RuboCop 1.62. The `prism/translation/parser/rubocop` file is deprecated."
+
 require "parser"
 require "rubocop"
 
@@ -27,9 +29,13 @@ module ProcessedSource
           # list of known parsers.
           def parser_class(ruby_version)
             if ruby_version == Prism::Translation::Parser::VERSION_3_3
+              warn "WARN: Setting `TargetRubyVersion: 80_82_73_83_77.33` is deprecated. " \
+                   "Set to `ParserEngine: parser_prism` and `TargetRubyVersion: 3.3` instead."
               require "prism/translation/parser33"
               Prism::Translation::Parser33
             elsif ruby_version == Prism::Translation::Parser::VERSION_3_4
+              warn "WARN: Setting `TargetRubyVersion: 80_82_73_83_77.34` is deprecated. " \
+                   "Set to `ParserEngine: parser_prism` and `TargetRubyVersion: 3.4` instead."
               require "prism/translation/parser34"
               Prism::Translation::Parser34
             else
@@ -41,9 +47,13 @@ def parser_class(ruby_version)
           # list of known parsers.
           def parser_class(ruby_version, _parser_engine)
             if ruby_version == Prism::Translation::Parser::VERSION_3_3
+              warn "WARN: Setting `TargetRubyVersion: 80_82_73_83_77.33` is deprecated. " \
+                   "Set to `ParserEngine: parser_prism` and `TargetRubyVersion: 3.3` instead."
               require "prism/translation/parser33"
               Prism::Translation::Parser33
             elsif ruby_version == Prism::Translation::Parser::VERSION_3_4
+              warn "WARN: Setting `TargetRubyVersion: 80_82_73_83_77.34` is deprecated. " \
+                   "Set to `ParserEngine: parser_prism` and `TargetRubyVersion: 3.4` instead."
               require "prism/translation/parser34"
               Prism::Translation::Parser34
             else