fix(fs): fix copying of symlink directories on Windows

[IgorM867]

This PR fixes the handling of symlink directories in the copy function on Windows. Previously, copying a directory that was a symlink resulted in creating a symlink of type "file" instead of "dir".

The test case for copying symlink directories passed because Deno.lstat() (which does not follow symlinks) was used. However, when Deno.stat() (which follows symlinks) was used on this type of symlink, the system would throw a PermissionDenied error.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.34%. Comparing base (8573618) to head (d2e0c60).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6278   +/-   ##
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  Coverage   96.34%   96.34%           
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  Files         543      543           
  Lines       41601    41601           
  Branches     6312     6310    -2     
=======================================
+ Hits        40079    40081    +2     
+ Misses       1478     1477    -1     
+ Partials       44       43    -1     

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[kt3k]

Thanks @IgorM867 for working on this!

I merged #6236 and this branch at #6280, but the CI shows some errors. Do you see the reason for those errors?

[IgorM867]

@kt3k The reason is that in the copySymLink() function, when copying a symlink, await Deno.readLink(src); returns only a relative path ("dir"), not the full path. I believe this is due to how the symlinks were initially created. When I recreated them on Windows, all the tests passed.

[jbronder]

Using Deno.realPath should return the absolute path of the symlink target. Additional explanation for suggestion in PR #6236:

Suggested change

	const originSrcFilePath = await Deno.readLink(src);
	const originSrcFilePath = await Deno.realPath(src);

[kt3k]

I think changing this to realPath causes another problem. I think we should keep this work for relative symlinks.

[jbronder]

Using Deno.realPathSync should return the absolute path of the symlink target. Additional explanation for suggestion in PR #6236:

Suggested change

	const originSrcFilePath = Deno.readLinkSync(src);
	const originSrcFilePath = Deno.realPathSync(src);

[kt3k]

I think this only works when originSrcFilePath is an absolute path or relative path accidentally points to path accessible from cwd. originSrcFilePath could be relative path from link path to target, which could be inaccessible from cwd, and in that case this lstat call would fail.

I think this should Deno.stat(src) instead with fallback to 'file' type in case Deno.stat(src) throws NotFound. What do you think?