Windows: Errors in teststandard/processes/streamio.tst in the master branch

[olexandr-konovalov]

See for example this Jenkins build (St Andrews only)

########> Diff in /proc/cygdrive/C/Users/jenkins/workspace/GAP-master-windows-\
build/GAP-master-snapshot/tst/teststandard/processes/streamio.tst:28
# Input is:
ForAny([1..10], x -> checkPartialRead(write, ReadLine, "aaa", "aaa\n"));
# Expected output:
true
# But found:
Error, Missing second
########
########> Diff in /proc/cygdrive/C/Users/jenkins/workspace/GAP-master-windows-\
build/GAP-master-snapshot/tst/teststandard/processes/streamio.tst:30
# Input is:
ForAny([1..10], x -> checkPartialRead(write, ReadLine, "aaa", "aaa"));
# Expected output:
true
# But found:
Error, Missing second
########
########> Diff in /proc/cygdrive/C/Users/jenkins/workspace/GAP-master-windows-\
build/GAP-master-snapshot/tst/teststandard/processes/streamio.tst:32
# Input is:
ForAny([1..10], x -> checkPartialRead(write, ReadAll, "aaa", "aaa\n"));
# Expected output:
true
# But found:
Error, Missing second
########
########> Diff in /proc/cygdrive/C/Users/jenkins/workspace/GAP-master-windows-\
build/GAP-master-snapshot/tst/teststandard/processes/streamio.tst:38
# Input is:
c := ReadByte(process);
# Expected output:
97
# But found:
fail
########
########> Diff in /proc/cygdrive/C/Users/jenkins/workspace/GAP-master-windows-\
build/GAP-master-snapshot/tst/teststandard/processes/streamio.tst:40
# Input is:
c := ReadByte(process);
# Expected output:
98
# But found:
fail
########
########> Diff in /proc/cygdrive/C/Users/jenkins/workspace/GAP-master-windows-\
build/GAP-master-snapshot/tst/teststandard/processes/streamio.tst:42
# Input is:
c := ReadByte(process);
# Expected output:
99
# But found:
fail
########
########> Diff in /proc/cygdrive/C/Users/jenkins/workspace/GAP-master-windows-\
build/GAP-master-snapshot/tst/teststandard/processes/streamio.tst:44
# Input is:
c := ReadByte(process);
# Expected output:
100
# But found:
fail
########
########> Diff in /proc/cygdrive/C/Users/jenkins/workspace/GAP-master-windows-\
build/GAP-master-snapshot/tst/teststandard/processes/streamio.tst:46
# Input is:
c := ReadByte(process);
# Expected output:
101
# But found:
fail
########
########> Diff in /proc/cygdrive/C/Users/jenkins/workspace/GAP-master-windows-\
build/GAP-master-snapshot/tst/teststandard/processes/streamio.tst:48
# Input is:
c := ReadByte(process);
# Expected output:
102
# But found:
fail
########

[olexandr-konovalov]

Still happens - e.g. in St Andrews only link tonight. This blocks GAP 4.11 and needs addressing.

[olexandr-konovalov]

Still happens - e.g. in St Andrews only link and thus blocks GAP 4.11.

[embray]

What's an easy way to run just the tests in tst/teststandard/processes/streamio.tst so I can try it myself?

[olexandr-konovalov]

Test("C:/gap-path-to-your-installation/tst/teststandard/processes/streamio.tst");

[embray]

I think the problem is just with the test, and it's not too surprising it fails in CI. I can't reproduce it manually, so far.

It might help to debug if the like if ReadLine(process) <> secondread then Error("Missing second"); fi; also output what it did read, because otherwise it just says "Missing second".

[embray]

Nevermind, I can recreate the same failures if I modify slowwrite.sh to just exit -11 (for example). It's possible that this test is suffering from the same fork failures that were discussed e.g. on #2890?

[fingolfin]

@embray yes, that is possible; which is why I wonder whether my PR #3513 might help with this.

[olexandr-konovalov]

@fingolfin @embray As I wrote in #3513, it does not fix errors from this issue.

[wilfwilson]

Note that this test file, teststandard/processes/streamio.tst, was only added in 28th January 2019 in #3236. In particular, it was added after GAP 4.10, and not long before this issue was created.

I think it is possible, perhaps even likely, that this file would have also failed in GAP 4.10. (Although I have no way of testing this). I propose that we simply disable this test on Windows and proceed with a GAP 4.11 release, which contains many benefits to users on all platforms.

[ChrisJefferson]

I also can't get this test to fail, it works fine on both 32-bit and 64-bit

Are you running on a machine with no 'sh'? That would explain the failure.