Comparing dirs with symlinks does not work

[mat007]

The following test

func TestSymlinks(t *testing.T) {
	rootDirectory := fs.NewDir(t, "root",
		fs.WithDir("source",
			fs.WithFile("foo.txt", "foo"),
			fs.WithSymlink("fool.txt", "foo.txt"),
			fs.WithSymlink("sourcel", "source")))
	defer rootDirectory.Remove()
	expected := fs.Expected(t,
		fs.WithDir("source",
			fs.WithFile("foo.txt", "foo"),
			fs.WithSymlink("fool.txt", "foo.txt"),
			fs.WithSymlink("sourcel", "source")))
	assert.Assert(t, fs.Equal(rootDirectory.Path(), expected))
}

fails on Mac with Go 1.11 with

--- FAIL: TestTarSymlinks (0.00s)
    ....._test.go:82: assertion failed: directory /var/folders/3f/77_0lxwn02x9v1rxz9314qzc0000gp/T/root-331223324 does not match expected:
        /source/fool.txt
          mode: expected Lrwxrwxrwx got Lrwxr-xr-x
          target: expected foo.txt got /var/folders/3f/77_0lxwn02x9v1rxz9314qzc0000gp/T/root-331223324/source/foo.txt
        /source/sourcel
          mode: expected Lrwxrwxrwx got Lrwxr-xr-x
          target: expected source got /var/folders/3f/77_0lxwn02x9v1rxz9314qzc0000gp/T/root-331223324/source/source

Did I miss something obvious?

[dnephin]

os.Symlink seems to create links with mode os.ModeSymlink | 0777 on linux (and os.ModeSymlink | 0666 on windows). From your output it seems that on darwin the default is os.ModeSymlink | 0755 ? If that is the case (and it's not a setting in your environment) I guess we need a fs/manifest_darwin.go to set a defaultSymlinkMode.

fs.Symlink creates a target with an absolute path, so I guess it is not symmetrical when used on a manifest. This feels like a bug to me. I'm not sure how easy that will be to fix.

[dnephin]

Created #192 for the WithSymlink problem