_symlinks attempts to create multiple symbolic links to .../include

[olaaaf]

When pkg-config returns paths with multiples of .../include the function _symlinks attempts (and fails via java.io.IOException) to create multiple symbolic links of the same path.

To replicate this issue run pkg-config gtkmm-4.0 --cflags --libs

The simplest solution is to modify the name of the final directory that is created. An attempt to create sub-directories to hold these include directories may, in turn, create cyclical symbolic links inside the system directory.

[magreenblatt]

A simple fix is to check if the path exists here before trying to create the symlink:

def _symlinks(ctx, basename, srcpaths):
    result = []
    root = ctx.path("")
    base = root.get_child(basename)
    rootlen = len(str(base)) - len(basename)
    for src in [ctx.path(p) for p in srcpaths]:
        dest = base.get_child(src.basename)
        if not dest.exists:
            ctx.symlink(src, dest)
        result += [str(dest)[rootlen:]]
    return result

[olaaaf]

Sorry I had a pull request ready but removed the forked repo. You can take a look at #3