Merge branch 'js/ignore-space-at-eol' into maint

An age old bug that caused "git diff --ignore-space-at-eol"
misbehave has been fixed.

* js/ignore-space-at-eol:
  diff: fix a double off-by-one with --ignore-space-at-eol
  diff: demonstrate a bug with --patience and --ignore-space-at-eol

Author: gitster

t/t4033-diff-patience.sh

@@ -5,6 +5,14 @@ test_description='patience diff algorithm'
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-diff-alternative.sh
 
+test_expect_success '--ignore-space-at-eol with a single appended character' '
+	printf "a\nb\nc\n" >pre &&
+	printf "a\nbX\nc\n" >post &&
+	test_must_fail git diff --no-index \
+		--patience --ignore-space-at-eol pre post >diff &&
+	grep "^+.*X" diff
+'
+
 test_diff_frobnitz "patience"
 
 test_diff_unique "patience"

xdiff/xpatience.c

@@ -1,6 +1,6 @@
 /*
  *  LibXDiff by Davide Libenzi ( File Differential Library )
- *  Copyright (C) 2003-2009 Davide Libenzi, Johannes E. Schindelin
+ *  Copyright (C) 2003-2016 Davide Libenzi, Johannes E. Schindelin
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Lesser General Public

xdiff/xutils.c

@@ -200,8 +200,10 @@ int xdl_recmatch(const char *l1, long s1, const char *l2, long s2, long flags)
 				return 0;
 		}
 	} else if (flags & XDF_IGNORE_WHITESPACE_AT_EOL) {
-		while (i1 < s1 && i2 < s2 && l1[i1++] == l2[i2++])
-			; /* keep going */
+		while (i1 < s1 && i2 < s2 && l1[i1] == l2[i2]) {
+			i1++;
+			i2++;
+		}
 	}
 
 	/*