[foreign] test_time timezone trouble (TZ)

[Jonathan Gibbons]

Jorn,

There is only limited amount of support for setting env variables in 
jtreg tests, because at least in the
early releases of JDK, the use of environment variables was discouraged.

Using `@run shell unsettz.sh` will not have the desired effect because 
it will only affect the shell
that is created to run your shell script, and will not have a persistent 
environment on any other
process.

If you don't mind always setting a command-line option, you might try 
using `-eTZ=` on the jtreg
command-line, which will unset TZ for all tests, although it would be 
more accurate to say that
it will not set it for any tests.

The only way to change the setting of TZ for any specific test will be 
to do one of the
following:

1. Write the test as a shell script that unsets TZ and then runs any 
Java code, using various
     shell environment variables that will be available; these generally 
begin with "TEST".

2. Write the test as a Java program that execs a child process to run 
Java, with the exact set
     of environment variables you want to pass in. There are system 
properties that identify
     the test JDK, test class path and so on; these generally begin with 
"test.".

These days, writing shell tests is generally discouraged, because it is 
notoriously difficult to get it
right on all relevant platforms, and because these days, it is 
reasonably easy to use either
the Java SE Process[Builder] API or test library API to invoke java.

Hope that helps; if you have follow-up questions, please cc: me directly 
or use one of the jtreg-* aliases,
since I am not on the panama-dev list.

-- Jon

On 09/21/2018 02:12 PM, Michel Trudeau wrote:
> [adding jtreg mailing list to seek out answer about jtreg and TZ on Windows]
>
> On Sep 21, 2018, at 12:44 PM, Jorn Vernee <jbvernee at xs4all.nl> wrote:
>
> Hello guys,
>
> I was running into a problem with the test_time test in StdLibTest. The generator for test values was apparently generating invalid values. After fixing that, all the test iterations were failing because the hours were off by one (the output of LocalDateTime.getHours() is being compared to the output of localtime().hour()). Good thing somebody else on the internet seems to have had the same problem [1]. TL;DR when using the MSVC version of localtime, and when running in cygwin, the function tries to interpret the TZ environment variable, but since that has a unix format (courtesy of cygwin), the interpretation fails and defaults to GMT. When TZ is not set, it defaults to the system default timezone, which is also what's being tested against.
>
> I can get the tests to pass by using `unset TZ` in the cygwin terminal before running them, but I'd have to do that every time I reboot it. I was trying to unset TZ automatically by using jtreq `@run shell unsettz.sh` where unsettz.sh is a file containing just the command `unset TZ`. It seems to be running successfully according to the test output:
>
> ACTION: shell -- Passed. Execution successful
> REASON: User specified action: run shell unsettz.sh
> TIME:   0.126 seconds
> messages:
> command: shell unsettz.sh
> reason: User specified action: run shell unsettz.sh
> elapsed time (seconds): 0.126
> STDOUT:
> STDERR:
>
> But it doesn't seem to affect the tests itself, and they still fail (still off by 1 hour).
>
> I was wondering if there is a way to let jtreg control environment variables? Or maybe you can suggest a different solution?
>
> The jtreg guide [2] mentions that TZ will be propagated from Windows 'if set', but I need it to be not set, or automatically set to the system's default time zone (by default it's blank).
>
> (other than that, tests are looking good: `passed: 24; failed: 4; error: 1`. I just need to fix structs by value, which on Windows cheats and just passes a pointer. 2 failing tests are from jextract missing)
>
> Thanks,
> Jorn
>
> [1] : https://stackoverflow.com/q/11655003
> [2] : http://openjdk.java.net/jtreg/tag-spec.html
>