these commits have no parents.
*********************************************************
-The basic idea is to write the SHA1s of shallow commits into
+The basic idea is to write the SHA-1s of shallow commits into
$GIT_DIR/shallow, and handle its contents like the contents
of $GIT_DIR/info/grafts (with the difference that shallow
cannot contain parent information).
at all (even throughout development of the shallow clone, it
was never manually edited!).
-Each line contains exactly one SHA1. When read, a commit_graft
+Each line contains exactly one SHA-1. When read, a commit_graft
will be constructed, which has nr_parent < 0 to make it easier
to discern from user provided grafts.