[fix] Remove useless processing of jruby.compat.version for JRuby 10 compatibility

chadlwilson · chadlwilson · commit 27cbe141bfcd · 2026-04-17T23:05:16.000+08:00
This has been set to 2.1 for all supported JRubies for a long time, and the setting did nothing
within JRuby. This change reduces usages, and introduce a stub to allow testing with JRuby 10; where rspec and others logic will still try and locate the class.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,5 +1,6 @@
 ## 1.2.7 (UNRELEASED)
 
+- Fix compatibility with JRuby 10.0 and Rails 8.0 (#419)
 - Fix ability to include and forward to JSPs under Rails (#370)
 - Update (bundled) rack to 2.2.23 (#417)
 
diff --git a/README.md b/README.md
@@ -13,11 +13,11 @@ For more information on Rack, visit http://rack.github.io/.
 
 ## Compatibility
 
-| JRuby-Rack Series                                              | Status        | Rack      | JRuby     | Java | Rails     | Target Servlet API | Notes                                                          |
-|----------------------------------------------------------------|---------------|-----------|-----------|------|-----------|--------------------|----------------------------------------------------------------|
-| [**1.2**](https://github.com/jruby/jruby-rack/tree/1.2-stable) | Maintained    | 2.2       | 9.3 → 9.4 | 8+   | 5.0 → 7.2 | 3.0 (Java EE 6)    | ✅ _Unofficial_: Servlet 3.1 → 4.0 also OK with most containers |
-| [**1.1**](https://github.com/jruby/jruby-rack/tree/1.1-stable) | EOL @ 2024-05 | 1.x → 2.2 | 1.6 → 9.4 | 6+   | 2.1 → 5.2 | 2.5 (Java EE 5)    | ✅ _Unofficial_: Servlet 3.0 → 4.0 also OK with most containers |
-| [**1.0**](https://github.com/jruby/jruby-rack/tree/1.0.10)     | EOL @ 2011-11 | 0.9 → 1.x | 1.1 → 1.9 | 5+   | 2.1 → 3.x | 2.5 (Java EE 5)    |                                                                |
+| JRuby-Rack Series                                              | Status        | Rack      | JRuby      | Java | Rails     | Target Servlet API | Notes                                                          |
+|----------------------------------------------------------------|---------------|-----------|------------|------|-----------|--------------------|----------------------------------------------------------------|
+| [**1.2**](https://github.com/jruby/jruby-rack/tree/1.2-stable) | Maintained    | 2.2       | 9.3 → 10.0 | 8+   | 5.0 → 8.0 | 3.0 (Java EE 6)    | ✅ _Unofficial_: Servlet 3.1 → 4.0 also OK with most containers |
+| [**1.1**](https://github.com/jruby/jruby-rack/tree/1.1-stable) | EOL @ 2024-05 | 1.x → 2.2 | 1.6 → 9.4  | 6+   | 2.1 → 5.2 | 2.5 (Java EE 5)    | ✅ _Unofficial_: Servlet 3.0 → 4.0 also OK with most containers |
+| [**1.0**](https://github.com/jruby/jruby-rack/tree/1.0.10)     | EOL @ 2011-11 | 0.9 → 1.x | 1.1 → 1.9  | 5+   | 2.1 → 3.x | 2.5 (Java EE 5)    |                                                                |
 
 ## Getting Started
 
@@ -209,8 +209,6 @@ as context init parameters in web.xml or as VM-wide system properties.
   sub-path of the main servlet context root.
 - `gem.path`: Relative path to the bundled gem repository. Defaults to
   `/WEB-INF/gems`.
-- `jruby.compat.version`: Set to "1.8" or "1.9" to make JRuby run a specific
-  version of Ruby (same as the --1.8 / --1.9 command line flags).
 - `jruby.min.runtimes`: For non-threadsafe Rails applications using a runtime
   pool, specify an integer minimum number of runtimes to hold in the pool.
 - `jruby.max.runtimes`: For non-threadsafe Rails applications, an integer
diff --git a/src/main/java/org/jruby/rack/DefaultRackApplicationFactory.java b/src/main/java/org/jruby/rack/DefaultRackApplicationFactory.java
@@ -302,10 +302,6 @@ protected RubyInstanceConfig initRuntimeConfig(final RubyInstanceConfig config)
         // Process arguments, namely any that might be in RUBYOPT
         config.processArguments(rackConfig.getRuntimeArguments());
 
-        if ( rackConfig.getCompatVersion() != null ) {
-            config.setCompatVersion(rackConfig.getCompatVersion());
-        }
-
         try { // try to set jruby home to jar file path
             final URL resource = Ruby.class.getResource("/META-INF/jruby.home");
             if ( resource != null && "jar".equals( resource.getProtocol() ) ) {
diff --git a/src/main/java/org/jruby/rack/DefaultRackConfig.java b/src/main/java/org/jruby/rack/DefaultRackConfig.java
@@ -17,16 +17,12 @@
 import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.Map;
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
 
 import org.jruby.CompatVersion;
 import org.jruby.rack.logging.OutputStreamLogger;
 import org.jruby.rack.logging.StandardOutLogger;
 import org.jruby.util.SafePropertyAccessor;
 
-import static org.jruby.rack.RackLogger.Level.WARN;
-
 /**
  * A base implementation of that retrieves settings from system properties.
  *
@@ -81,23 +77,6 @@ public void setQuiet(boolean quiet) {
 
     @Override
     public CompatVersion getCompatVersion() {
-        final String version = getProperty("jruby.compat.version");
-        if ( version != null ) {
-            // we handle 1.8, RUBY1_9, --2.0 1_9 2.1.0.dev etc :
-            final Pattern pattern = Pattern.compile("([123])[._]([8901234567])");
-            final Matcher matcher = pattern.matcher(version);
-            if ( matcher.find() ) {
-                final String name = "RUBY" +
-                    matcher.group(1) + '_' + matcher.group(2);
-                try {
-                    return Enum.valueOf(CompatVersion.class, name);
-                }
-                catch (IllegalArgumentException e) {
-                    getLogger().log(WARN,
-                        "could not resolve compat version from '"+ version +"' will use default", e);
-                }
-            }
-        }
         return null;
     }
 
diff --git a/src/main/java/org/jruby/rack/RackConfig.java b/src/main/java/org/jruby/rack/RackConfig.java
@@ -36,7 +36,10 @@ public interface RackConfig {
     /** 
      * Return the Ruby version that JRuby should run.
      * @return <code>RUBY_VERSION</code> (e.g. 1.8, 1.9)
+     *
+     * @deprecated Since jruby-rack 1.2 (and JRuby 9.2), for removal in 1.3.0
      */
+    @Deprecated
     CompatVersion getCompatVersion();
 
     /** 
diff --git a/src/main/java/org/jruby/rack/embed/Config.java b/src/main/java/org/jruby/rack/embed/Config.java
@@ -44,7 +44,6 @@ public class Config implements RackConfig {
 
     private RackLogger logger;
     private Map<String, String> rubyENV;
-    private CompatVersion compatVersion;
 
     public Config() {
         delegate = new DefaultRackConfig() {
@@ -66,7 +65,6 @@ public void doInitialize(final Ruby runtime) {
         setOut( runtime.getOut() );
         setErr( runtime.getErr() );
         rubyENV = runtime.getENV();
-        compatVersion = runtime.getInstanceConfig().getCompatVersion();
     }
 
 
@@ -106,9 +104,15 @@ public final Number getNumberProperty(String key, Number defaultValue) {
         return delegate.getNumberProperty(key, defaultValue);
     }
 
+    /**
+     * @return Always CompatVersion.RUBY2_1, consistent with JRuby 9.3+
+     *
+     * @deprecated Since jruby-rack 1.2 (and JRuby 9.2), for removal in 1.3.0
+     */
+    @Deprecated
     @Override
     public CompatVersion getCompatVersion() {
-        return compatVersion;
+        return CompatVersion.RUBY2_1;
     }
 
     @Override
diff --git a/src/main/ruby/jruby/rack/core_ext.rb b/src/main/ruby/jruby/rack/core_ext.rb
@@ -15,7 +15,7 @@ class Exception
   include JRuby::Rack::Capture::Environment if $DEBUG
   include JRuby::Rack::Capture::RubyGems
   include JRuby::Rack::Capture::Bundler
-  include JRuby::Rack::Capture::JRubyRackConfig
+  include JRuby::Rack::Capture::JRubyRackConfig if JRUBY_VERSION.start_with?("9.") # Workaround for JRuby 10 with missing CompatVerison class
   include JRuby::Rack::Capture::JavaEnvironment if $DEBUG
 end
 
diff --git a/src/spec/java/org/jruby/CompatVersion.java b/src/spec/java/org/jruby/CompatVersion.java
@@ -0,0 +1,17 @@
+package org.jruby;
+
+/**
+ * This was removed from JRuby Core as of 10.0; but deprecated and unused for a long time.
+ * <p/>
+ * While this is not actually used at runtime unless people specifically invoke the methods on Rack Config, various
+ * tests mock RackConfig which causes tests to try and load the class. So we add back/override a minimal version here
+ * to allow the tests to work on JRuby 10, and be able to add JRuby 10 and Rails 8.0 support to the 1.2.x line.
+ * <p/>>
+ * @link <a href="https://github.com/jruby/jruby/blob/jruby-9.4/core/src/main/java/org/jruby/CompatVersion.java">...</a>
+ * @deprecated since JRuby 9.2 with no replacement; for removal with jruby-rack 1.3.0
+ */
+public enum CompatVersion {
+    RUBY1_8, // used in specs
+    RUBY2_1, // used as default by jruby-rack
+    BOTH     // used as the default by JRuby 9.3/9.4 at runtime
+}
diff --git a/src/spec/ruby/jruby/rack/error_app_spec.rb b/src/spec/ruby/jruby/rack/error_app_spec.rb
@@ -165,7 +165,7 @@ def in_tmpdir_with_files(files = {})
     end
     yield path
   ensure
-    FileUtils.rm_rf(path) if path && File.exists?(path)
+    FileUtils.rm_rf(path) if path && File.exist?(path)
   end
 
 end
diff --git a/src/spec/ruby/jruby/rack/integration_spec.rb b/src/spec/ruby/jruby/rack/integration_spec.rb
@@ -19,8 +19,6 @@
     before do
       @servlet_context = org.jruby.rack.mock.RackLoggingMockServletContext.new "file://#{STUB_DIR}/rack"
       @servlet_context.logger = raise_logger
-      # make sure we always boot runtimes in the same mode as specs :
-      set_compat_version @servlet_context
     end
 
     it "initializes" do
@@ -260,16 +258,10 @@ def new_servlet_context(base_path = nil)
   end
 
   def prepare_servlet_context(servlet_context, base_path)
-    set_compat_version servlet_context
     servlet_context.addInitParameter('rails.root', base_path)
     servlet_context.addInitParameter('jruby.rack.layout_class', 'FileSystemLayout')
   end
 
-  def set_compat_version(servlet_context = @servlet_context); require 'jruby'
-    compat_version = JRuby.runtime.getInstanceConfig.getCompatVersion # RUBY1_9
-    servlet_context.addInitParameter("jruby.compat.version", compat_version.to_s)
-  end
-
   GEMFILES_DIR = File.expand_path('../../../gemfiles', STUB_DIR)
 
   def copy_gemfile
diff --git a/src/spec/ruby/rack/application_spec.rb b/src/spec/ruby/rack/application_spec.rb
@@ -390,13 +390,6 @@ def newRuntime()
         should_eval_as_eql_to "require 'yaml'", true # -ryaml not processed
       end
 
-      it "handles jruby.compat.version == '1.9' and starts in 1.9 mode" do
-        set_config 'jruby.compat.version', '1.9'
-        #@rack_config.stub(:getCompatVersion).and_return org.jruby.CompatVersion::RUBY1_9
-        @runtime = app_factory.new_runtime
-        expect(@runtime.is1_9).to be_truthy
-      end
-
       it "handles jruby.runtime.arguments == '-X+O -Ke' and start with object space enabled and KCode EUC" do
         set_config 'jruby.runtime.arguments', '-X+O -Ke'
         # allow(@rack_config).to receive(:getRuntimeArguments).and_return ['-X+O', '-Ke'].to_java(:String)
diff --git a/src/spec/ruby/rack/capture_spec.rb b/src/spec/ruby/rack/capture_spec.rb
@@ -13,15 +13,31 @@
   before :each do
     JRuby::Rack.context = nil
     $servlet_context = @servlet_context
-    allow(@servlet_context).to receive(:init_parameter_names).and_return []
+    allow(@servlet_context).to receive(:config).and_return Java::OrgJrubyRackEmbed::Config.new
   end
 
   it "captures environment information" do
     expect(@servlet_context).to receive(:log)
-    error = StandardError.new
+    error = StandardError.new "simulated rack start-up failed"
     error.capture
     error.store
     expect(error.output).to be_a StringIO
+    expect(error.output.string).to include "An exception happened during JRuby-Rack startup"
+    expect(error.output.string).to include "simulated rack start-up failed"
+    expect(error.output.string).to include "--- System"
+    expect(error.output.string).to include "jruby #{JRUBY_VERSION}"
+    expect(error.output.string).to include "--- Context Init Parameters:"
+    expect(error.output.string).to include "--- RubyGems"
+    expect(error.output.string).to include "Gem.path:"
+    expect(error.output.string).to include "--- Bundler"
+    expect(error.output.string).to include "Gemfile:"
+    if JRUBY_VERSION.start_with?("9.")
+      expect(error.output.string).to include "--- JRuby-Rack Config"
+      expect(error.output.string).to include "logger_class_name"
+    else
+      # This is disabled on JRuby 10 to avoid CompatVersion missing class issues without breaking backward compat
+      expect(error.output.string).not_to include "--- JRuby-Rack Config"
+    end
   end
 
   it "captures exception backtrace" do
@@ -34,4 +50,5 @@
     end
   end
 
+
 end
diff --git a/src/spec/ruby/rack/config_spec.rb b/src/spec/ruby/rack/config_spec.rb
@@ -184,56 +184,10 @@ def expect_empty_env(env)
 
   end
 
-  it "sets compat version from init parameter" do
-    expect(@servlet_context).to receive(:getInitParameter).with("jruby.compat.version").
-      and_return "RUBY1_9"
-    expect( config.getCompatVersion ).to be org.jruby.CompatVersion::RUBY1_9
-  end
-
-  it "sets compat version from init parameter (dot syntax)" do
-    expect(@servlet_context).to receive(:getInitParameter).with("jruby.compat.version").
-      and_return "1.8"
-    expect( config.getCompatVersion ).to be org.jruby.CompatVersion::RUBY1_8
-  end
-
-  it "leaves compat version nil if not specified" do
-    expect(@servlet_context).to receive(:getInitParameter).with("jruby.compat.version").
-      and_return nil
+  it "always returns nil compat version (backwards compat)" do
     expect( config.getCompatVersion ).to be nil
   end
 
-  it "leaves compat version nil if invalid value specified" do
-    expect(@servlet_context).to receive(:getInitParameter).with("jruby.compat.version").
-      and_return "4.2"
-    expect( config.getCompatVersion ).to be nil
-  end
-
-    it "sets compat version from init parameter (head-syntax)" do
-      expect(@servlet_context).to receive(:getInitParameter).with("jruby.compat.version").
-        and_return "1.9.3-SNAPSHOT"
-      expect( config.getCompatVersion ).to be org.jruby.CompatVersion::RUBY1_9
-    end
-
-  if JRUBY_VERSION >= '1.7.0'
-    it "sets compat version 2.0 from init parameter" do
-      expect(@servlet_context).to receive(:getInitParameter).with("jruby.compat.version").
-        and_return "RUBY2_0"
-      expect( config.getCompatVersion ).to be org.jruby.CompatVersion::RUBY2_0
-    end
-
-    it "sets compat version 2.0 from init parameter (dot syntax)" do
-      expect(@servlet_context).to receive(:getInitParameter).with("jruby.compat.version").
-        and_return "2_0"
-      expect( config.getCompatVersion ).to be org.jruby.CompatVersion::RUBY2_0
-    end
-
-    it "sets compat version 2.0 from init parameter (head-syntax)" do
-      expect(@servlet_context).to receive(:getInitParameter).with("jruby.compat.version").
-        and_return "2.0.0.dev"
-      expect( config.getCompatVersion ).to be org.jruby.CompatVersion::RUBY2_0
-    end
-  end
-
   describe "custom-properties" do
 
     it "parser an int property" do
diff --git a/src/spec/ruby/rack/embed/config_spec.rb b/src/spec/ruby/rack/embed/config_spec.rb
@@ -58,10 +58,8 @@
       end
     end
 
-    it "sets compat version from runtime" do
-      require 'jruby'
-      compat_version = JRuby.runtime.instance_config.compat_version
-      expect( @config.compat_version ).to eql compat_version
+    it "always returns default runtime compat version (backwards compat)" do
+      expect( @config.compat_version ).to eql Java::OrgJRuby::CompatVersion::RUBY2_1
     end
 
     it "sets out/err streams from runtime" do
