fix(tar): enable unix paths in tar RootPath

[sensslen]

Fix Path RootPath property usage in TarArchive by applying the same transformation as used when stripping a TarEntry path.

see #581 #338

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[Numpsy]

this PR seems to include a set of Zip changes from one of the other (unmerged) async related PRs, rather than being against the master branch or being just the described issue?

[sensslen]

You are correct - I got confused by that branch that was called something like origin/.../master. Sorry! I corrected this mistake.

[piksel]

Yeah, that's what the gh tool does when you check out PRs. I should rename it.

[sensslen]

Is there anything witholding this PR to be merged? We're curently spinning our own version of SharpZipLib which includes this fix but I would really like to get rid of it as soon as possible!

[piksel]

Well, there are some problems with DropPathRoot. It will throw exceptions on .NET 4.6 if you give it certain paths which alters the behaviour (and can throw upon reading files etc, which isn't great).
See #593 which deals with this. I think I have found all the problems with it though, so that should be merged pretty soon. The plan is to use it for all the path handling code that is currently split between zip and tar. It would basically just slot in as a replacement for the ClearTarPath() method in this PR.

[sensslen]

Good to hear, that you are working on this issue. Looking forward to the next release

[piksel]

Added suggestions (that can be batch-commited if you want) for using the shared DropPathRoot and reuse of existing test helpers.

[sensslen]

Thanks a lot for your suggestions. They do absolutely make sense. Just out of curiosity. Didn't #593 address this issue already and this PR is thus obsolete now?

[codecov]

Codecov Report

Merging #582 (f1b175a) into master (79614c5) will increase coverage by 0.41%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #582      +/-   ##
==========================================
+ Coverage   74.13%   74.54%   +0.41%     
==========================================
  Files          71       72       +1     
  Lines        8450     8450              
==========================================
+ Hits         6264     6299      +35     
+ Misses       2186     2151      -35     

Impacted Files	Coverage Δ
src/ICSharpCode.SharpZipLib/Tar/TarArchive.cs	48.70% <100.00%> (+4.63%)	⬆️
src/ICSharpCode.SharpZipLib/Tar/TarEntry.cs	78.44% <100.00%> (+10.65%)	⬆️
.../ICSharpCode.SharpZipLib/Tar/TarStringExtension.cs	100.00% <100.00%> (ø)
src/ICSharpCode.SharpZipLib/Tar/TarHeader.cs	84.47% <0.00%> (+3.61%)	⬆️

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[sensslen]

I'd love to hear why this PR is still not merged....

[piksel]

I'd love to hear why this PR is still not merged....

I have been busy with life and other projects. It's still in the pipeline for 1.4.

[sensslen]

I'd love to hear why this PR is still not merged....

I have been busy with life and other projects. It's still in the pipeline for 1.4.

No Worries