REVISIONS" section in linkgit:git-rev-parse) means the
commits in the specified range.
-A single commit, when interpreted as a <revision range>
-expression, means "everything that leads to that commit", but
-if you write 'git format-patch <commit>', the previous rule
-applies to that command line and you do not get "everything
-since the beginning of the time". If you want to format
-everything since project inception to one commit, say "git
-format-patch \--root <commit>" to make it clear that it is the
-latter case. If you want to format a single commit, you can do
-this with "git format-patch -1 <commit>".
+The first rule takes precedence in the case of a single <commit>. To
+apply the second rule, i.e., format everything since the beginning of
+history up until <commit>, use the '\--root' option: "git format-patch
+\--root <commit>". If you want to format only <commit> itself, you
+can do this with "git format-patch -1 <commit>".
By default, each output file is numbered sequentially from 1, and uses the
first line of the commit message (massaged for pathname safety) as
applied. By default the contents of changes in those files are
+ Treat the revision argument as a <revision range>, even if it
+ is just a single commit (that would normally be treated as a
+ <since>). Note that root commits included in the specified
+ range are always formatted as creation patches, independently
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