diff --git a/git-send-email.perl b/git-send-email.perl
index 79cc5bee9..fd8bfff3b 100755
--- a/git-send-email.perl
+++ b/git-send-email.perl
@@ -512,8 +512,9 @@ sub split_addrs {
 
 ($sender) = expand_aliases($sender) if defined $sender;
 
-# returns 1 if the conflict must be solved using it as a format-patch argument
-sub check_file_rev_conflict($) {
+# is_format_patch_arg($f) returns 0 if $f names a patch, or 1 if
+# $f is a revision list specification to be passed to format-patch.
+sub is_format_patch_arg {
 	return unless $repo;
 	my $f = shift;
 	try {
@@ -529,6 +530,7 @@ ($)
     * Giving --format-patch option if you mean a range.
 EOF
 	} catch Git::Error::Command with {
+		# Not a valid revision.  Treat it as a filename.
 		return 0;
 	}
 }
@@ -540,14 +542,14 @@ ($)
 	if ($f eq "--") {
 		push @rev_list_opts, "--", @ARGV;
 		@ARGV = ();
-	} elsif (-d $f and !check_file_rev_conflict($f)) {
+	} elsif (-d $f and !is_format_patch_arg($f)) {
 		opendir my $dh, $f
 			or die "Failed to opendir $f: $!";
 
 		push @files, grep { -f $_ } map { catfile($f, $_) }
 				sort readdir $dh;
 		closedir $dh;
-	} elsif ((-f $f or -p $f) and !check_file_rev_conflict($f)) {
+	} elsif ((-f $f or -p $f) and !is_format_patch_arg($f)) {
 		push @files, $f;
 	} else {
 		push @rev_list_opts, $f;