pre-applypatch
--------------
-This hook is invoked by `git-am`. It takes no parameter,
-and is invoked after the patch is applied, but before a commit
-is made. Exiting with non-zero status causes the working tree
-after application of the patch not committed.
+This hook is invoked by `git-am`. It takes no parameter, and is
+invoked after the patch is applied, but before a commit is made.
+
+If it exits with non-zero status, then the working tree will not be
+committed after applying the patch.
It can be used to inspect the current working tree and refuse to
make a commit if it does not pass certain test.