jruby
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
@@ -72,7 +72,34 @@ jobs:
 
     strategy:
       matrix:
-        target: ['test:mri:core:jit', 'test:mri:extra', 'spec:ruby:fast:jit', 'test:mri:stdlib', 'spec:ruby:slow', 'spec:ruby:debug', 'test:jruby:aot', 'test:slow_suites', 'spec:compiler', 'spec:regression', 'spec:jruby', 'spec:jrubyc', 'spec:profiler']
+        target: ['test:mri:core:jit', 'test:mri:extra', 'spec:ruby:fast:jit', 'test:mri:stdlib', 'spec:ruby:slow', 'spec:ruby:debug', 'test:jruby:aot', 'test:slow_suites', 'spec:compiler', 'spec:regression', 'spec:jrubyc', 'spec:profiler']
+      fail-fast: false
+
+    name: rake ${{ matrix.target }} (Java 8)
+
+    steps:
+      - name: checkout
+        uses: actions/checkout@v3
+      - name: set up java 8
+        uses: actions/setup-java@v3
+        with:
+          distribution: 'zulu'
+          java-version: '8'
+          cache: 'maven'
+      - name: bootstrap
+        run: mvn -ntp -Pbootstrap clean package
+      - name: bundle install
+        run: bin/jruby --dev -S bundle install
+      - name: rake ${{ matrix.target }}
+        run: bin/jruby -S rake ${{ matrix.target }}
+
+  rake-test-8-multiplatform:
+    runs-on: ${{ matrix.platform }}
+
+    strategy:
+      matrix:
+        target: ['spec:jruby']
+        platform: ['ubuntu-latest', 'macos-latest']
       fail-fast: false
 
     name: rake ${{ matrix.target }} (Java 8)

diff --git a/core/src/main/java/org/jruby/util/Dir.java b/core/src/main/java/org/jruby/util/Dir.java
@@ -43,6 +43,7 @@
 import static org.jruby.util.ByteList.memcmp;
 import static org.jruby.util.StringSupport.EMPTY_STRING_ARRAY;
 import static org.jruby.util.StringSupport.codePoint;
+import static org.jruby.util.StringSupport.memchr;
 
 /**
  * This class exists as a counterpart to the dir.c file in
@@ -760,6 +761,9 @@ private static int findScheme(byte[] path, int begin, int end) {
         if (schemeStr.startsWith("uri:")) return 4;
         if (schemeStr.startsWith("file:")) return 5;
         if (schemeStr.startsWith("classpath:")) return 10;
+        if (schemeStr.startsWith("jar:file:")) {
+            return memchr(path, begin, '!', end - begin) + 1;
+        }
         return -1;
     }
 
@@ -819,11 +823,15 @@ private static int addToResultIfExists(Ruby runtime, String cwd, byte[] bytes, i
 
     private static int glob_helper(Ruby runtime, String cwd, ByteList path, int sub, int flags, GlobFunc<GlobArgs> func, GlobArgs arg) {
         int begin = path.getBegin();
-        final int end = begin + path.length();
+        int end = begin + path.length();
         final Encoding enc = path.getEncoding();
-        final byte[] bytes = path.getUnsafeBytes();
+        byte[] bytes = path.getUnsafeBytes();
         final byte[] scheme = extractScheme(bytes, begin, end);
-        if (scheme != null) begin += scheme.length;
+        if (scheme != null) {
+            bytes = Arrays.copyOfRange(bytes, begin + scheme.length, end);
+            begin = 0;
+            end = bytes.length;
+        }
         return glob_helper(runtime, cwd, scheme, bytes, begin, end, enc, sub, flags, func, arg);
     }
 
@@ -1004,7 +1012,10 @@ private static int glob_helper(Ruby runtime, String cwd, byte[] scheme,
                     for ( DirGlobber globber : links ) {
                         final ByteList link = globber.link;
                         if ( status == 0 ) {
-                            resource = JRubyFile.createResource(runtime, cwd, new String(link.unsafeBytes(), link.begin(), link.length(), enc.getCharset()));
+                            String fullPath = scheme != null ?
+                                    new String(prependScheme(scheme, link.unsafeBytes(), link.begin(), link.length()), enc.getCharset()) :
+                                    new String(link.unsafeBytes(), link.begin(), link.length(), enc.getCharset());
+                            resource = JRubyFile.createResource(runtime, cwd, fullPath);
                             if ( resource.isDirectory() ) {
                                 final int len = link.getRealSize();
                                 buf.length(0);

diff --git a/core/src/main/java/org/jruby/util/JarResource.java b/core/src/main/java/org/jruby/util/JarResource.java
@@ -33,6 +33,9 @@ else if (pathname.startsWith("file:")) {
         // normalize path -- issue #2017
         if (StringSupport.startsWith(entryPath, '/', '/')) entryPath = entryPath.substring(1);
 
+        // special case: "jar:file:blah.jar!." is just "jar:file:blah.jar!"
+        if (entryPath.equals(".")) entryPath = "";
+
         // TODO: Do we really need to support both test.jar!foo/bar.rb and test.jar!/foo/bar.rb cases?
         JarResource resource = createJarResource(jarPath, entryPath, false);
 

diff --git a/spec/jruby/core/dir/fixtures/test1.txt b/spec/jruby/core/dir/fixtures/test1.txt
@@ -0,0 +1 @@
+test1
diff --git a/spec/jruby/core/dir/fixtures/test2.txt b/spec/jruby/core/dir/fixtures/test2.txt
@@ -0,0 +1 @@
+test2
diff --git a/spec/jruby/core/dir/fixtures/test3.txt b/spec/jruby/core/dir/fixtures/test3.txt
@@ -0,0 +1 @@
+test3
diff --git a/spec/jruby/core/dir/fixtures/testdir/test4.txt b/spec/jruby/core/dir/fixtures/testdir/test4.txt
@@ -0,0 +1 @@
+test4
diff --git a/spec/jruby/core/dir/glob_spec.rb b/spec/jruby/core/dir/glob_spec.rb
@@ -1,5 +1,6 @@
 require 'rspec'
 require 'fileutils'
+require 'tmpdir'
 
 describe "Dir.glob" do
   let(:dir_name) { 'test_dir!' }
@@ -17,15 +18,111 @@
   it 'can glob directories with URI special chars in it (GH-2264)' do
     expect(Dir.glob("#{dir_name}/**/*").size).to eq 1
   end
-end
 
-describe "Dir.glob" do
   # We have common option processing code and a logic mistake made
   # us process argv[2] as both a kwarg then try to convert it to an
   # integer.
   it "does not think the third arg should be an integer when it is kwargs" do
     expect { Dir["*", "*", base: "."] }.not_to raise_error
   end
+
+  describe "with a uri:classloader: scheme" do
+    before :all do
+      # FIXME: unsanitary because we can't clear entries from $CLASSPATH
+      $CLASSPATH << __dir__
+    end
+
+    it "can find a specific file" do
+      test1_files = Dir.glob("uri:classloader:/fixtures/test1.txt")
+      expect(test1_files[0]).to eq "uri:classloader:/fixtures/test1.txt"
+      expect(File.read(test1_files[0])).to eq "test1"
+    end
+
+    it "can find a set of files for a wildcard filename" do
+      test_txt_files = Dir.glob("uri:classloader:/fixtures/test*.txt")
+      expect(test_txt_files).to eq %w[test1 test2 test3].map { "uri:classloader:/fixtures/#{_1}.txt" }
+      test_txt_files.each { expect(File.read(_1)).to eq File.basename(_1).split(".").first }
+
+      test_txt_files = Dir.glob("uri:classloader:/fixtures/test?.txt")
+      expect(test_txt_files).to eq %w[test1 test2 test3].map { "uri:classloader:/fixtures/#{_1}.txt" }
+      test_txt_files.each { expect(File.read(_1)).to eq File.basename(_1).split(".").first }
+    end
+
+    it "can find a specific file in a double star path" do
+      test5_files = Dir.glob("uri:classloader:/fixtures/**/test4.txt")
+      expect(test5_files[0]).to eq "uri:classloader:/fixtures/testdir/test4.txt"
+      expect(File.read(test5_files[0])).to eq "test4"
+    end
+  end
+
+  describe "with a file: scheme" do
+    it "can find a specific file" do
+      test1_files = Dir.glob("file:#{__dir__}/fixtures/test1.txt")
+      expect(test1_files[0]).to eq "file:#{__dir__}/fixtures/test1.txt"
+      expect(File.read(test1_files[0])).to eq "test1"
+    end
+
+    it "can find a set of files for a wildcard filename" do
+      test_txt_files = Dir.glob("file:#{__dir__}/fixtures/test*.txt")
+      expect(test_txt_files).to eq %w[test1 test2 test3].map { "file:#{__dir__}/fixtures/#{_1}.txt" }
+      test_txt_files.each { expect(File.read(_1)).to eq File.basename(_1).split(".").first }
+
+      test_txt_files = Dir.glob("file:#{__dir__}/fixtures/test?.txt")
+      expect(test_txt_files).to eq %w[test1 test2 test3].map { "file:#{__dir__}/fixtures/#{_1}.txt" }
+      test_txt_files.each { expect(File.read(_1)).to eq File.basename(_1).split(".").first }
+    end
+
+    it "can find a specific file in a double star path" do
+      test5_files = Dir.glob("file:#{__dir__}/fixtures/**/test4.txt")
+      expect(test5_files[0]).to eq "file:#{__dir__}/fixtures/testdir/test4.txt"
+      expect(File.read(test5_files[0])).to eq "test4"
+    end
+  end
+
+  describe "with a jar:file: scheme" do
+    before :all do
+      tmpdir = Dir.mktmpdir
+      @test_files_jar = "#{tmpdir}/spec_jruby_dir_glob.jar"
+      system "jar cf #{@test_files_jar} -C #{__dir__} fixtures"
+    end
+
+    after :all do
+      FileUtils.rm_f @test_files_jar
+    end
+
+    it "can find a specific file" do
+      test1_files = Dir.glob("jar:file:#{@test_files_jar}!fixtures/*")
+      expect(test1_files[0]).to eq "jar:file:#{@test_files_jar}!fixtures/test1.txt"
+      expect(File.read(test1_files[0])).to eq "test1"
+    end
+
+    it "can find a set of files for a wildcard filename" do
+      test_txt_files = Dir.glob("jar:file:#{@test_files_jar}!fixtures/test*.txt")
+      expect(test_txt_files).to eq %w[test1 test2 test3].map { "jar:file:#{@test_files_jar}!fixtures/#{_1}.txt" }
+      test_txt_files.each { expect(File.read(_1)).to eq File.basename(_1).split(".").first }
+
+      test_txt_files = Dir.glob("jar:file:#{@test_files_jar}!fixtures/test?.txt")
+      expect(test_txt_files).to eq %w[test1 test2 test3].map { "jar:file:#{@test_files_jar}!fixtures/#{_1}.txt" }
+      test_txt_files.each { expect(File.read(_1)).to eq File.basename(_1).split(".").first }
+    end
+
+    it "can find a specific file in a double star path" do
+      test5_files = Dir.glob("jar:file:#{@test_files_jar}!fixtures/**/test4.txt")
+      expect(test5_files[0]).to eq "jar:file:#{@test_files_jar}!fixtures/testdir/test4.txt"
+      expect(File.read(test5_files[0])).to eq "test4"
+    end
+
+    it "can find a specific file in a \".\" relative path" do
+      test1_files = Dir.glob("jar:file:#{@test_files_jar}!./fixtures/test1.txt")
+      expect(test1_files[0]).to eq "jar:file:#{@test_files_jar}!./fixtures/test1.txt"
+      expect(File.read(test1_files[0])).to eq "test1"
+    end
+
+    it "treats a bare \".\" path as its own entry" do
+      test1_files = Dir.glob("jar:file:#{@test_files_jar}!.")
+      expect(test1_files[0]).to eq "jar:file:#{@test_files_jar}!."
+    end
+  end
 end
 
 
diff --git a/spec/jruby/core/file/absolute_path_spec.rb b/spec/jruby/core/file/absolute_path_spec.rb
@@ -15,6 +15,7 @@
 
   # This represents internal paths for files contain within jar files.
   it "should return itself for 'classpath:uri:/'" do
+    skip("jruby/jruby#8981") if RbConfig::CONFIG['host_os']
     ['classpath:uri:/', 'classpath:uri:/home/me'].each do |path|
       expect(File.absolute_path(path)).to eq path
     end