[GHC] #15021: ghc-pkg list crashes on Windows when unicode character is in the path

[GHC]

#15021: ghc-pkg list crashes on Windows when unicode character is in the path
---------------------------------+----------------------------------------
        Reporter:  nh2           |                Owner:  (none)
            Type:  bug           |               Status:  new
        Priority:  normal        |            Milestone:  8.6.1
       Component:  ghc-pkg       |              Version:  8.2.2
      Resolution:                |             Keywords:
Operating System:  Windows       |         Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown  |            Test Case:
      Blocked By:                |             Blocking:
 Related Tickets:  #10762        |  Differential Rev(s):
       Wiki Page:                |
---------------------------------+----------------------------------------

Comment (by lehins):

 I can confirm this issue with Cyrillic characters on Windows 7 with latest
 GHC. If locale set to Russian through the control panel everything works
 fine, but changing the codepage does break {{{ghc-pkg}}}
 {{{
 PS C:\Users\Алексей\ghc-8.4.2\bin> chcp 437
 Active code page: 437
 PS C:\Users\???????\ghc-8.4.2\bin> .\ghc-pkg.exe list
 C:\Users\ghc-pkg.exe: <stdout>: commitBuffer: invalid argument (invalid
 character)
 PS C:\Users\???????\ghc-8.4.2\bin> chcp 866
 Active code page: 866
 PS C:\Users\Алексей\ghc-8.4.2\bin> .\ghc-pkg.exe list
 C:\Users\Алексей\ghc-8.4.2\lib\package.conf.d
     Cabal-2.2.0.1
     Win32-2.6.1.0
     array-0.5.2.0
     base-4.11.1.0
     binary-0.8.5.1
     bytestring-0.10.8.2
     containers-0.5.11.0
     deepseq-1.4.3.0
     directory-1.3.1.5
     filepath-1.4.2
     (ghc-8.4.2)
     ghc-boot-8.4.2
     ghc-boot-th-8.4.2
     ghc-compact-0.1.0.0
     ghc-prim-0.5.2.0
     ghci-8.4.2
     haskeline-0.7.4.2
     hpc-0.6.0.3
     integer-gmp-1.0.2.0
     mtl-2.2.2
     parsec-3.1.13.0
     pretty-1.1.3.6
     process-1.6.3.0
     rts-1.0
     stm-2.4.5.0
     template-haskell-2.13.0.0
     text-1.2.3.0
     time-1.8.0.2
     transformers-0.5.5.0
     xhtml-3000.2.2.1

 PS C:\Users\Алексей\ghc-8.4.2\bin>
 }}}


 Curiously, setting {{{chcp 65001}}} when locale is already set to Russian
 through the control panel results in a powershell crash, but not when
 locale is English(United States).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15021#comment:1>
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