1 files changed, 1 insertions, 1 deletions
diff --git a/hash.c b/hash.c
index 6cddb8cf0b..e170e67660 100644
--- a/hash.c
+++ b/hash.c
@@ -2411,7 +2411,7 @@ env_fetch(int argc, VALUE *argv)
     if (!env) {
 	if (block_given) return rb_yield(key);
 	if (argc == 1) {
-	    rb_raise(rb_eKeyError, "key not found");
+	    rb_raise(rb_eKeyError, "key not found: \"%"PRIsVALUE"\"", key);
 	}
 	return if_none;
     }