1 files changed, 8 insertions, 0 deletions
diff --git a/range-diff.h b/range-diff.h
index 583ced2e8e..c17dbc2e75 100644
--- a/range-diff.h
+++ b/range-diff.h
@@ -16,4 +16,12 @@ int show_range_diff(const char *range1, const char *range2,
 		    const struct diff_options *diffopt,
 		    const struct strvec *other_arg);
 
+/*
+ * Determine whether the given argument is usable as a range argument of `git
+ * range-diff`, e.g. A..B. Note that this only validates the format but does
+ * _not_ parse it, i.e. it does _not_ look up the specified commits in the
+ * local repository.
+ */
+int is_range_diff_range(const char *arg);
+
 #endif