On 03/11/21 8:50 am, Jaikiran Pai wrote:
Hello Alan,
On 02/11/21 5:30 pm, Alan Bateman wrote:
On 02/11/2021 06:38, Jaikiran Pai wrote:
:
Perhaps run 1 writing the hash code of each of the boot modules'
descriptor into a file and then run 2 reading that same file to
compare the hash codes would be one way to do it. But I think that
would just make this test more complex, which I think is avoidable.
I'm not sure that we really need this. There are several jlink tests
that check reproducibility, we think one of them is failing
intermittently with this issue already. So maybe we should leave
build reproducibility to the jlink tests and expand them as needed.
For ModuleDescriptor::hashCode then I was hoping we keep it simple
and just test that the hashCode of the descriptors for modules in the
boot layer matches the hashCode computed from re-parsing the
module-info files, e.g. something simple like this:
for (Module module : ModuleLayer.boot().modules()) {
System.out.println(module);
ModuleDescriptor descriptor1 = module.getDescriptor();
ModuleDescriptor descriptor2;
try (InputStream in =
module.getResourceAsStream("module-info.class")) {
descriptor2 = ModuleDescriptor.read(in);
}
assertEquals(descriptor1, descriptor2);
assertEquals(descriptor1.hashCode(),
descriptor2.hashCode());
assertEquals(descriptor1.compareTo(descriptor2), 0);
}
It run can twice, with with the default, the other with -Xshare:off.
Sounds reasonable. I've updated the PR to simplify the test and run it
once with default CDS and once with -Xshare:off. Given this
simplification, it now allows me to use testng for these comparisons,
so I've moved it from regular "main" to testng test case. I hope
that's OK.
Test continues to pass with these changes and fails (as expected) when
the fix in the source code of ModuleDescriptor class is rolled back.
-Jaikiran
