publishCanonicalLinkNoReplace checked the destination with lstat and
then published, leaving a window the comment claimed did not exist: on
Windows renameSync replaces a concurrent object outright (libuv passes
MOVEFILE_REPLACE_EXISTING), and on POSIX ln -P source target links INTO
a directory that appeared at the target, leaving a stray link inside
foreign data that the rollback list never recorded. Create the symlink
or junction directly at the destination instead — link creation fails
with EEXIST when anything occupies the path and never treats the target
as a container, so the publication itself is the atomic no-replace
check. Identity confirmation re-reads the live link before the
publication enters the rollback list. Covered by injected concurrent
creators at the publish instant on POSIX and simulated Windows,
asserting the foreign object and its contents stay completely
unchanged.
玉澜
2b131a1031