RFR: 8303920: Avoid calling out to python in DataDescriptorSignatureMissing test [v4]

[Jaikiran Pai]

On Fri, 10 Mar 2023 08:28:37 GMT, Eirik Bjorsnos <duke at openjdk.org> wrote:

>> Please review this PR which brings  the DataDescriptorSignatureMissing test back to life.
>> 
>> This test currently calls out to Python to create a test vector ZIP with a Data Descriptor without the recommended but optional signature. The Python dependency has turned out to be very brittle, so the test is currently marked with `@ignore` 
>> 
>> The PR replaces Python callouts with directly creating the test vector ZIP in the test itself. We can then remove the `@ignore`tag and run this useful test automatically.
>
> Eirik Bjorsnos has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Revert change to Google copyright line, add an Oracle copyright line instead.

It's good that this test is being revived and no longer relies on an external tool/program to generate a zip which was triggering the issue in https://bugs.openjdk.org/browse/JDK-8056934.

The changes look good to me. In order to verify that without the fix in https://bugs.openjdk.org/browse/JDK-8056934, this test fails (i.e. reproduces the issue), I reverted the fix that was done in that issue (`git revert 3951dda4cf06c6e61e19d3df26a792022c1701b9`) and then built the JDK and ran this updated test. It runs into a NullPointerException within the test because the second entry in the zip is missing after the zip is read through the `ZipInputStream`. Could you add this following patch to your test:


diff --git a/test/jdk/java/util/zip/DataDescriptorSignatureMissing.java b/test/jdk/java/util/zip/DataDescriptorSignatureMissing.java
index 5efdc59de63..636cecb4851 100644
--- a/test/jdk/java/util/zip/DataDescriptorSignatureMissing.java
+++ b/test/jdk/java/util/zip/DataDescriptorSignatureMissing.java
@@ -39,6 +39,7 @@ import java.nio.charset.StandardCharsets;
 import java.util.zip.*;
 
 import static org.testng.Assert.assertEquals;
+import static org.testng.Assert.assertNotNull;
 
 public class DataDescriptorSignatureMissing {
 
@@ -55,10 +56,12 @@ public class DataDescriptorSignatureMissing {
         try (ZipInputStream in = new ZipInputStream(
                 new ByteArrayInputStream(zip))) {
             ZipEntry first = in.getNextEntry();
+            assertNotNull(first, "Zip file is unexpectedly missing first entry");
             assertEquals(first.getName(), "first");
             assertEquals(in.readAllBytes(), "first".getBytes(StandardCharsets.UTF_8));
 
             ZipEntry second = in.getNextEntry();
+            assertNotNull(second, "Zip file is unexpectedly missing second entry");
             assertEquals(second.getName(), "second");
             assertEquals(in.readAllBytes(), "second".getBytes(StandardCharsets.UTF_8));
         }



so that instead of running into a NullPointerException, the test will (rightly) reproduce and report the missing second entry?

-------------

PR: https://git.openjdk.org/jdk/pull/12959