range-diff/format-patch: refactor check for commit range
Currently, when called with exactly two arguments, `git range-diff`
tests for a literal `..` in each of the two. Likewise, the argument
provided via `--range-diff` to `git format-patch` is checked in the same
manner.
However, `<commit>^!` is a perfectly valid commit range, equivalent to
`<commit>^..<commit>` according to the `SPECIFYING RANGES` section of
gitrevisions[7].
In preparation for allowing more sophisticated ways to specify commit
ranges, let's refactor the check into its own function.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/range-diff.c b/range-diff.c
index b9950f1..9b93e08 100644
--- a/range-diff.c
+++ b/range-diff.c
@@ -564,3 +564,8 @@ int show_range_diff(const char *range1, const char *range2,
return res;
}
+
+int is_range_diff_range(const char *arg)
+{
+ return !!strstr(arg, "..");
+}
