Prism is always present on Ruby 3.3

Allows to remove some compatibility code with ripper

Author: Earlopain

.github/workflows/ci.yml

@@ -34,7 +34,9 @@ jobs:
       matrix:
         ruby: ${{ fromJson(needs.ruby-versions.outputs.versions) }}
         prism_version:
-          - 1.2.0 # Shipped with Ruby 3.4 as default parser https://www.ruby-lang.org/en/news/2024/12/25/ruby-3-4-0-released/
+          # See https://stdgems.org/prism for which ruby version shipped with which prism version
+          - 0.19.0
+          - 1.2.0
           - 1.8.0
           - head
     env:
@@ -53,22 +55,3 @@ jobs:
       - name: test
         run: bin/rake test
         continue-on-error: ${{ matrix.ruby == 'head' }}
-
-  test-disable-prism:
-    needs: ruby-versions
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        ruby: ${{ fromJson(needs.ruby-versions.outputs.versions) }}
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v6
-      - name: Set up Ruby
-        uses: ruby/setup-ruby@v1
-        with:
-          ruby-version: ${{ matrix.ruby }}
-          bundler-cache: true
-      - name: test
-        run: SYNTAX_SUGGEST_DISABLE_PRISM=1 bin/rake test
-        continue-on-error: ${{ matrix.ruby == 'head' }}

lib/syntax_suggest/api.rb

@@ -7,26 +7,12 @@
 require "pathname"
 require "timeout"
 
+# Prism is the new parser, replacing Ripper
+require "prism"
 # We need Ripper loaded for `Prism.lex_compat` even if we're using Prism
 # for lexing and parsing
 require "ripper"
 
-# Prism is the new parser, replacing Ripper
-#
-# We need to "dual boot" both for now because syntax_suggest
-# supports older rubies that do not ship with syntax suggest.
-#
-# We also need the ability to control loading of this library
-# so we can test that both modes work correctly in CI.
-if (value = ENV["SYNTAX_SUGGEST_DISABLE_PRISM"])
-  warn "Skipping loading prism due to SYNTAX_SUGGEST_DISABLE_PRISM=#{value}"
-else
-  begin
-    require "prism"
-  rescue LoadError
-  end
-end
-
 module SyntaxSuggest
   # Used to indicate a default value that cannot
   # be confused with another input.
@@ -35,14 +21,6 @@ module SyntaxSuggest
   class Error < StandardError; end
   TIMEOUT_DEFAULT = ENV.fetch("SYNTAX_SUGGEST_TIMEOUT", 1).to_i
 
-  # SyntaxSuggest.use_prism_parser? [Private]
-  #
-  # Tells us if the prism parser is available for use
-  # or if we should fallback to `Ripper`
-  def self.use_prism_parser?
-    defined?(Prism)
-  end
-
   # SyntaxSuggest.handle_error [Public]
   #
   # Takes a `SyntaxError` exception, uses the
@@ -152,20 +130,11 @@ def self.valid_without?(without_lines:, code_lines:)
   # SyntaxSuggest.invalid? [Private]
   #
   # Opposite of `SyntaxSuggest.valid?`
-  if defined?(Prism)
-    def self.invalid?(source)
-      source = source.join if source.is_a?(Array)
-      source = source.to_s
+  def self.invalid?(source)
+    source = source.join if source.is_a?(Array)
+    source = source.to_s
 
-      Prism.parse(source).failure?
-    end
-  else
-    def self.invalid?(source)
-      source = source.join if source.is_a?(Array)
-      source = source.to_s
-
-      Ripper.new(source).tap(&:parse).error?
-    end
+    Prism.parse(source).failure?
   end
 
   # SyntaxSuggest.valid? [Private]

lib/syntax_suggest/explain_syntax.rb

@@ -2,18 +2,10 @@
 
 require_relative "left_right_lex_count"
 
-if !SyntaxSuggest.use_prism_parser?
-  require_relative "ripper_errors"
-end
-
 module SyntaxSuggest
   class GetParseErrors
     def self.errors(source)
-      if SyntaxSuggest.use_prism_parser?
-        Prism.parse(source).errors.map(&:message)
-      else
-        RipperErrors.new(source).call.errors
-      end
+      Prism.parse(source).errors.map(&:message)
     end
   end
 

lib/syntax_suggest/lex_all.rb

@@ -40,14 +40,8 @@ def initialize(source:, source_lines: nil)
       }
     end
 
-    if SyntaxSuggest.use_prism_parser?
-      def self.lex(source, line_number)
-        Prism.lex_compat(source, line: line_number).value.sort_by { |values| values[0] }
-      end
-    else
-      def self.lex(source, line_number)
-        Ripper::Lexer.new(source, "-", line_number).parse.sort_by(&:pos)
-      end
+    def self.lex(source, line_number)
+      Prism.lex_compat(source, line: line_number).value.sort_by { |values| values[0] }
     end
 
     def to_a

lib/syntax_suggest/ripper_errors.rb

@@ -8,12 +8,6 @@
 
 module SyntaxSuggest
   RSpec.describe "Top level SyntaxSuggest api" do
-    it "doesn't load prism if env var is set" do
-      skip("SYNTAX_SUGGEST_DISABLE_PRISM not set") unless ENV["SYNTAX_SUGGEST_DISABLE_PRISM"]
-
-      expect(SyntaxSuggest.use_prism_parser?).to be_falsey
-    end
-
     it "has a `handle_error` interface" do
       fake_error = Object.new
       def fake_error.message