Here's the failing assert on macOS:

WARNING: Using incubator modules: jdk.incubator.jpackage
java.lang.AssertionError: Expected [0]. Actual [134]: Check command [/REMOVED/jdkContents/Home/bin/jpackage --input ./test.f79b089b/input --dest ./test.f79b089b/output --name IconTest --type dmg --main-jar hello.jar --main-class Hello --icon /REMOVED/test/jdk/tools/jpackage/resources/icon2.icns --resource-dir ./test.f79b089b/resources.0 --runtime-image ./test.f79b089b/fake_runtime --verbose](20) exited with 0 code
at jdk.jpackage.test.TKit.error(TKit.java:234)
at jdk.jpackage.test.TKit.assertEquals(TKit.java:528)
at jdk.jpackage.test.Executor$Result.assertExitCodeIs(Executor.java:164)
at jdk.jpackage.test.Executor.execute(Executor.java:198)
at jdk.jpackage.test.JPackageCommand.execute(JPackageCommand.java:630)
at jdk.jpackage.test.PackageTest$Handler.accept(PackageTest.java:499)
at jdk.jpackage.test.PackageTest$2.accept(PackageTest.java:428)
at jdk.jpackage.test.PackageTest$2.accept(PackageTest.java:377)
at jdk.jpackage.test.Functional$ThrowingConsumer.lambda$toConsumer$0(Functional.java:37)
at java.base/java.lang.Iterable.forEach(Iterable.java:75)
at jdk.jpackage.test.PackageTest.lambda$runActions$20(PackageTest.java:341)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1510)
at jdk.jpackage.test.PackageTest.lambda$runActions$21(PackageTest.java:340)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1510)
at jdk.jpackage.test.PackageTest.runActions(PackageTest.java:339)
at jdk.jpackage.test.RunnablePackageTest.run(RunnablePackageTest.java:51)
at IconTest.test(IconTest.java:162)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at jdk.jpackage.test.MethodCall.accept(MethodCall.java:145)
at jdk.jpackage.test.TestInstance.run(TestInstance.java:224)
at jdk.jpackage.test.TKit.lambda$ignoreExceptions$6(TKit.java:135)
at jdk.jpackage.test.TKit.lambda$runTests$4(TKit.java:120)
at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1624)
at java.base/java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:658)
at jdk.jpackage.test.TKit.lambda$runTests$5(TKit.java:117)
at jdk.jpackage.test.Functional$ThrowingRunnable.lambda$toRunnable$0(Functional.java:101)
at jdk.jpackage.test.TKit.withExtraLogStream(TKit.java:103)
at jdk.jpackage.test.TKit.runTests(TKit.java:116)
at jdk.jpackage.test.Main.runTests(Main.java:79)
at jdk.jpackage.test.Main.lambda$main$2(Main.java:75)
at jdk.jpackage.test.Functional$ThrowingRunnable.lambda$toRunnable$0(Functional.java:101)
at jdk.jpackage.test.TKit.withExtraLogStream(TKit.java:103)
at jdk.jpackage.test.Main.main(Main.java:75)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:127)
at java.base/java.lang.Thread.run(Thread.java:832)