defer removing a binary after it's used causes OSError

[timotheecour]

I don't have a minimal example and it may be hard to reproduce so feel free to close this issue; but just wanted to mention it.

I never saw that error before; it looks like a bug; it only happens on windows; it occurs when a binary is removed in a defer statement, the binary being only used inside the block.

seems unrelated to the corresponding PR #10353

https://ci.appveyor.com/project/Araq/nim/builds/21708811

git rev-parse HEAD
fb4968a

relevant code snippet:
$nim/tests/misc/tparseopt.nim

  block: # fix #9842
    let exe = buildDir / "D20190112T145450".addFileExt(ExeExt)
    defer: removeFile exe
    let args = @["a1b", "a2 b", "", "a4\"b", "a5'b", r"a6\b", "a7\'b"]
    let cmd = "$# c -r --verbosity:0 -o:$# -d:testament_tparseopt $# $#" %
      [getCurrentCompilerExe(), exe, currentSourcePath(),
          args.quoteShellCommand]
    var ret = execCmdEx(cmd, options = {})
    if ret.exitCode != 0:
      # before bug fix, running cmd would show:
      # sh: -c: line 0: unexpected EOF while looking for matching `"'\n
      echo "exitCode: ", ret.exitCode, " cmd:", cmd
      doAssert false
    stripLineEnd(ret.output)
    assertEquals ret.output,

error log from appveyor:

JOINED: tests/misc/tparamsindefault.nim C
JOINED: tests/misc/tparedef.nim C
JOINED: tests/misc/tparsecombnum.nim C
FAIL: tests/misc/tparseopt.nim C
Test "tests\misc\tparseopt.nim" in category "misc"
Failure: reExitcodesDiffer
Expected:
exitcode: 0
Gotten:
exitcode: 1
Output:
parseopt
first round
kind: cmdLongOption	key:val  --  left:
second round
kind: cmdLongOption	key:val  --  left:
kind: cmdLongOption	key:val  --  debug:3
kind: cmdShortOption	key:val  --  l:4
kind: cmdShortOption	key:val  --  r:2
cmdLongOption foo
cmdLongOption path
parseoptNoVal
kind: cmdLongOption	key:val  --  left:
kind: cmdLongOption	key:val  --  debug:3
kind: cmdShortOption	key:val  --  l:
kind: cmdShortOption	key:val  --  r:2
kind: cmdLongOption	key:val  --  debug:2
kind: cmdLongOption	key:val  --  debug:1
kind: cmdShortOption	key:val  --  r:1
kind: cmdShortOption	key:val  --  r:0
kind: cmdShortOption	key:val  --  l:
kind: cmdShortOption	key:val  --  r:4
parseopt2
first round
kind: cmdLongOption	key:val  --  left:
second round
kind: cmdLongOption	key:val  --  left:
kind: cmdLongOption	key:val  --  debug:3
kind: cmdShortOption	key:val  --  l:4
kind: cmdShortOption	key:val  --  r:2
tparseopt.nim(124)       tparseopt
os.nim(1252)             removeFile
oserr.nim(67)            raiseOSError
Error: unhandled exception: The process cannot access the file because it is being used by another process.
 [OSError]
JOINED: tests/misc/tpos.nim C
PASS: tests/misc/tprep.nim C                                       ( 2.35937548 secs)

[nc-x]

works fine locally (windows 10 x64)

[timotheecour]

ya may be hard to repro; closing for now; if pops up again we can re-open ; thx for trying it locally

[timotheecour]

reopening as this happened in a completely unrelated PR (by @BontaVlad #10228) again: https://ci.appveyor.com/project/dom96/nim/builds/21635870

JOINED: tests/misc/tparamsindefault.nim C
JOINED: tests/misc/tparedef.nim C
JOINED: tests/misc/tparsecombnum.nim C
FAIL: tests/misc/tparseopt.nim C
Test "tests\misc\tparseopt.nim" in category "misc"
Failure: reExitcodesDiffer
Expected:
exitcode: 0
Gotten:
exitcode: 1
Output:
parseopt
first round
kind: cmdLongOption	key:val  --  left:
second round
kind: cmdLongOption	key:val  --  left:
kind: cmdLongOption	key:val  --  debug:3
kind: cmdShortOption	key:val  --  l:4
kind: cmdShortOption	key:val  --  r:2
cmdLongOption foo
cmdLongOption path
parseoptNoVal
kind: cmdLongOption	key:val  --  left:
kind: cmdLongOption	key:val  --  debug:3
kind: cmdShortOption	key:val  --  l:
kind: cmdShortOption	key:val  --  r:2
kind: cmdLongOption	key:val  --  debug:2
kind: cmdLongOption	key:val  --  debug:1
kind: cmdShortOption	key:val  --  r:1
kind: cmdShortOption	key:val  --  r:0
kind: cmdShortOption	key:val  --  l:
kind: cmdShortOption	key:val  --  r:4
parseopt2
first round
kind: cmdLongOption	key:val  --  left:
second round
kind: cmdLongOption	key:val  --  left:
kind: cmdLongOption	key:val  --  debug:3
kind: cmdShortOption	key:val  --  l:4
kind: cmdShortOption	key:val  --  r:2
tparseopt.nim(121)       tparseopt
os.nim(1252)             removeFile
oserr.nim(67)            raiseOSError
Error: unhandled exception: The process cannot access the file because it is being used by another process.
 [OSError]
JOINED: tests/misc/tpos.nim C

so there is a bug, we just need to find a minimal test case (and perhaps it is a flaky one)

note that I've patched tests/misc/tparseopt.nim as workaround but bug is still there

[Araq]

IME Windows' file deletion is simply buggy. Even Windows's very own explorer sometimes fails with errors like these. Closing.