Re: [PATCH v2 1/1] git-p4: auto-delete named temporary file

> From: "Philip.McGraw" <Philip.McGraw@bentley.com>
>
> Avoid double-open exceptions on Windows platform when
> calculating for lfs compressed size threshold
> (git-p4.largeFileCompressedThreshold) comparisons.
>
> Take new approach using the NamedTemporaryFile()
> file-like object as input to the ZipFile() which
> auto-deletes after implicit close leaving with scope.
>
> Original code had double-open exception on Windows
> platform because file still open from NamedTemporaryFile()
> using generated filename instead of object.
>
> Thanks to Andrey for patiently suggesting several
> iterations on this change for avoiding exceptions!
>
> Also print error details after resulting IOError to make
> debugging cause of exception less mysterious when it has
> nothing to do with "git version recent enough."
>
> Signed-off-by: Philip.McGraw <Philip.McGraw@bentley.com>
> Reviewed-by: Andrey Mazo <ahippo@yandex.com>
> ---

>  git-p4.py | 13 ++++++-------
>  1 file changed, 6 insertions(+), 7 deletions(-)
>
> diff --git a/git-p4.py b/git-p4.py
> index c71a6832e2..33bdb14fd1 100755
> --- a/git-p4.py
> +++ b/git-p4.py
> @@ -1158,17 +1158,15 @@ def exceedsLargeFileThreshold(self, relPath, contents):
>          if gitConfigInt('git-p4.largeFileCompressedThreshold'):
>              contentsSize = sum(len(d) for d in contents)
>              if contentsSize <= gitConfigInt('git-p4.largeFileCompressedThreshold'):
>                  return False
>              contentTempFile = self.generateTempFile(contents)
> -            compressedContentFile = tempfile.NamedTemporaryFile(prefix='git-p4-large-file', delete=False)
> -            zf = zipfile.ZipFile(compressedContentFile.name, mode='w')
> -            zf.write(contentTempFile, compress_type=zipfile.ZIP_DEFLATED)
> -            zf.close()
> -            compressedContentsSize = zf.infolist()[0].compress_size
> +            compressedContentFile = tempfile.NamedTemporaryFile(prefix='git-p4-large-file', delete=True)
> +            with zipfile.ZipFile(compressedContentFile, mode='w') as zf:
> +                zf.write(contentTempFile, compress_type=zipfile.ZIP_DEFLATED)
> +                compressedContentsSize = zf.infolist()[0].compress_size
>              os.remove(contentTempFile)
> -            os.remove(compressedContentFile.name)
>              if compressedContentsSize > gitConfigInt('git-p4.largeFileCompressedThreshold'):
>                  return True
>          return False
>  
>      def addLargeFile(self, relPath):
> @@ -3512,12 +3510,13 @@ def importHeadRevision(self, revision):
>          details["time"] = res["time"]
>  
>          self.updateOptionDict(details)
>          try:
>              self.commit(details, self.extractFilesFromCommit(details), self.branch)
> -        except IOError:
> +        except IOError as err:
>              print("IO error with git fast-import. Is your git version recent enough?")
> +            print("IO error details: {}".format(err))
>              print(self.gitError.read())
>  
>      def openStreams(self):
>          self.importProcess = subprocess.Popen(["git", "fast-import"],
>                                                stdin=subprocess.PIPE,
>
> base-commit: 1feeaaf26bff51996f9f96c6dc41ca0f95ab5fc4
> Pull-Request: https://github.com/gitgitgadget/git/pull/303