readme: fix typo in t/README: s/$((...)/$((...))/

Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>

diff --git a/t/README b/t/README
index a862924b5ed187bb428ee6aa0b3f915536e488c8..fe862293669a045704cb1633376cc3aec45e0c94 100644 (file)
--- a/t/README
+++ b/t/README
@@ -268,7 +268,7 @@ Writing test cases
   Bourne-only equivalents:
 
     - use $(...), not `...`, for command substitution;
-    - use $((...), not `expr ...`, for arithmetic processing;
+    - use $((...)), not `expr ...`, for arithmetic processing;
     - liberally use '!' to invert the exit status of a command, e.g.,
       in idioms like "if ! CMD; then ...", instead of relying on clumsy
       paraphrases like "if CMD; then :; else ...".