[GHC] #16405: Plugin tests are remarkably fragile on Windows

[GHC]

#16405: Plugin tests are remarkably fragile on Windows
-------------------------------------+-------------------------------------
           Reporter:  bgamari        |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.6.3
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 There is something odd afoot in the tests in `testsuite/tests/plugins` on
 Windows. In any given testsuite run at least half a dozen of these tests
 fail for one reason or another (often a timeout sometimes another). I'm
 collecting these failures here to try to make sense of them:
 {{{
 =====> T16260(normal) 6833 of 6839 [2, 14, 0]
 cd "plugins/T16260.run" && $MAKE -s --no-print-directory -C simple-plugin
 package.T16260 TOP=/c/GitLabRunner/builds/78d7d3f9/0/ghc/ghc/testsuite
 cd "plugins/T16260.run" && $MAKE -s --no-print-directory T16260  ---
 plugins/T16260.run/T16260.stdout.normalised        2019-03-06
 03:20:38.902713500 +0000
 +++ plugins/T16260.run/T16260.run.stdout.normalised     2019-03-06
 03:20:38.903686400 +0000
 @@ -1,4 +0,0 @@
 -False
 -None
 -True
 -Safe

 Actual stdout output differs from expected:
 diff -uw "plugins/T16260.run/T16260.stdout.normalised"
 "plugins/T16260.run/T16260.run.stdout.normalised"
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16405>
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