Implement StringScanner for TruffleRuby in pure Ruby

.github/workflows/ci.yml

@@ -29,13 +29,13 @@ jobs:
           - { os: windows-latest , ruby: mingw }
           - { os: windows-latest , ruby: mswin }
           - { os: ubuntu-latest , ruby: jruby-9.4 }
+          - { os: ubuntu-latest , ruby: truffleruby-33 } # using stdlib implementation, only a smoke test
+          - { os: ubuntu-latest , ruby: truffleruby-head } # using truffleruby.rb
         exclude:
           - { os: macos-latest , ruby: 2.4 }
           - { os: ubuntu-latest , ruby: 2.5 }
           - { os: macos-latest , ruby: 2.5 }
           - { os: windows-latest , ruby: head }
-          - { os: ubuntu-latest , ruby: truffleruby }
-          - { os: macos-latest , ruby: truffleruby }
           - { os: windows-latest , ruby: truffleruby }
           - { os: windows-latest , ruby: truffleruby-head }
 
@@ -68,15 +68,17 @@ jobs:
           name: gem-${{ matrix.os }}-${{ matrix.ruby }}
           path: pkg/
 
-      - run: echo 'TESTOPTS=-v --ignore-name=/unscan/' >> $GITHUB_ENV
-        if: ${{ startsWith(matrix.ruby, 'truffle') }}
-
       - run: bundle exec rake test
+        if: matrix.ruby != 'truffleruby-33'
 
       - run: gem install --verbose --backtrace pkg/*.gem
 
       - run: gem install test-unit-ruby-core test-unit
 
       - name: Run tests on the installed gem
         run: ruby run-test.rb ${TESTOPTS}
-        if: matrix.ruby != '2.4' # strscan is a default gem from 2.5
+        if: matrix.ruby != '2.4' && matrix.ruby != 'truffleruby-33' # strscan is a default gem from 2.5
+
+      - name: Smoke test for older truffleruby using stdlib
+        run: ruby -rstrscan -e 'puts $".grep(/strscan/); abort("failed") unless StringScanner.new("abc").scan(/a/) == "a"'
+        if: matrix.ruby == 'truffleruby-33'

Rakefile

@@ -20,6 +20,13 @@ namespace :version do
       "STRSCAN_VERSION = \"#{version.succ}\""
     end
     File.write(strscan_java_path, strscan_java)
+
+    strscan_truffleruby_path = "lib/strscan/truffleruby.rb"
+    strscan_truffleruby = File.read(strscan_truffleruby_path).gsub(/Version = '(.+?)'/) do
+      version = $1
+      "Version = '#{version.succ}'"
+    end
+    File.write(strscan_truffleruby_path, strscan_truffleruby)
   end
 end
 
@@ -31,7 +38,7 @@ if RUBY_ENGINE == "jruby"
     ext.target_version = '1.8'
     ext.ext_dir = 'ext/jruby'
   end
-  extra_require_path = "ext/jruby/lib"
+  extra_require_path = "lib"
 elsif RUBY_ENGINE == "ruby"
   require 'rake/extensiontask'
   Rake::ExtensionTask.new("strscan") do |x|

ext/strscan/strscan.c

@@ -2299,6 +2299,4 @@ Init_strscan(void)
     rb_define_method(StringScanner, "fixed_anchor?", strscan_fixed_anchor_p, 0);
 
     rb_define_method(StringScanner, "named_captures", strscan_named_captures, 0);
-
-    rb_require("strscan/strscan");
 }

lib/strscan.rb

@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+case RUBY_ENGINE
+when 'ruby'
+  require 'strscan.so'
+  require_relative 'strscan/strscan'
+when 'jruby'
+  require 'strscan.jar'
+  JRuby::Util.load_ext('org.jruby.ext.strscan.StringScannerLibrary')
+  require_relative 'strscan/strscan'
+when 'truffleruby'
+  if RUBY_ENGINE_VERSION.to_i >= 34
+    require 'strscan/truffleruby'
+  else
+    $LOAD_PATH.delete __dir__
+    require 'strscan'
+  end
+else
+  raise NotImplementedError, "Unknown Ruby: #{RUBY_ENGINE}"
+end