Use compatibility regex library for OSX/Darwin

diff --git a/t/t4008-diff-break-rewrite.sh b/t/t4008-diff-break-rewrite.sh
index 1287d2ad175fffe342386eaf1c04bc8d26fd72f4..26c2e4aa65c539c527ae8e2d71b5abb40c21fbbd 100755 (executable)
--- a/t/t4008-diff-break-rewrite.sh
+++ b/t/t4008-diff-break-rewrite.sh
@@ -122,11 +122,11 @@ test_expect_success \
     'run diff with -B -M' \
     'git diff-index -B -M "$tree" >current'
 
-# This should not mistake file0 as the copy source of new file1
-# due to type differences.
+# file0 changed from regular to symlink.  file1 is very close to the preimage of file0.
+# because we break file0, file1 can become a rename of it.
 cat >expected <<\EOF
 :100644 120000 f5deac7be59e7eeab8657fd9ae706fd6a57daed2 67be421f88824578857624f7b3dc75e99a8a1481 T     file0
-:100644 100644 6ff87c4664981e4397625791c8ea3bbb5f2279a3 f5deac7be59e7eeab8657fd9ae706fd6a57daed2 M100  file1
+:100644 100644 6ff87c4664981e4397625791c8ea3bbb5f2279a3 f5deac7be59e7eeab8657fd9ae706fd6a57daed2 R     file0   file1
 EOF
 
 test_expect_success \