grep-command: Ignore case if case-fold-search is non-nil

[Tino Calancha <tino.calancha@gmail.com>]

Hi,

Do you think `grep-compute-defaults' should add '-i', i.e., ignore case,
in the default `grep-command' when `case-fold-search' is non-nil?
Option '-i' is specified by POSIX, do we need to check if `grep-program'
support it?

Regards,
Tino
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From 5220d4858475f0825c01926456a8932079e3d0d7 Mon Sep 17 00:00:00 2001
From: Tino Calancha <tino.calancha@gmail.com>
Date: Sun, 18 Sep 2016 18:19:52 +0900
Subject: [PATCH] grep-compute-defaults: Ignore case if case-fold-search is
  non-nil

* lisp/progmodes/grep.el (grep-compute-defaults): Use option '-i'.
---
  lisp/progmodes/grep.el | 3 ++-
  1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lisp/progmodes/grep.el b/lisp/progmodes/grep.el
index f7f097b..ac871a1 100644
--- a/lisp/progmodes/grep.el
+++ b/lisp/progmodes/grep.el
@@ -590,7 +590,8 @@ grep-compute-defaults
      (unless (and grep-command grep-find-command
  		 grep-template grep-find-template)
        (let ((grep-options
-	     (concat (if grep-use-null-device "-n" "-nH")
+	     (concat (if grep-use-null-device "-n"
+                       (if case-fold-search "-nHi" "-nH"))
  		     (if (grep-probe grep-program
  				     `(nil nil nil "-e" "foo" 
,null-device)
  				     nil 1)
-- 
2.9.3

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