[GHC] #13375: ghc-pkg "cache is out of date" message breaks testsuite

[GHC]

#13375: ghc-pkg "cache is out of date" message breaks testsuite
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        Reporter:  bgamari           |                Owner:  (none)
            Type:  bug               |               Status:  infoneeded
        Priority:  highest           |            Milestone:  8.2.1
       Component:  ghc-pkg           |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Other             |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"30d69f404ba102da94423836f86fbec2fb4adaf9/ghc" 30d69f4/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="30d69f404ba102da94423836f86fbec2fb4adaf9"
 ghc-pkg: Consider .conf files when computing package db mtime

 We can no longer use the mtime of the containing directory since it now
 contains a lock file in addition to the .cache and .conf files.

 Fixes #13375.

 Test Plan: Validate on Windows

 Reviewers: austin, arybczak

 Subscribers: rwbarton, thomie

 Differential Revision: https://phabricator.haskell.org/D3289
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13375#comment:5>
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