operate on a <tree> object but automatically dereferences
<commit> and <tag> objects that point at a <tree>.
+<commit-ish>::
+ Indicates a commit or tag object name. A
+ command that takes a <commit-ish> argument ultimately wants to
+ operate on a <commit> object but automatically dereferences
+ <tag> objects that point at a <commit>.
+
<type>::
Indicates that an object type is required.
Currently one of: `blob`, `tree`, `commit`, or `tag`.