[PATCH] diff: consolidate test helper script pieces.

There were duplicate script pieces to help comparing diff
output, which this patch consolidates into the t/diff-lib.sh
library.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

t/diff-lib.sh

@@ -0,0 +1,35 @@
+:
+
+_x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
+_x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
+sanitize_diff_raw='/^:/s/ '"$_x40"' '"$_x40"' \([A-Z]\)[0-9]*	/ X X \1#	/'
+compare_diff_raw () {
+    # When heuristics are improved, the score numbers would change.
+    # Ignore them while comparing.
+    # Also we do not check SHA1 hash generation in this test, which
+    # is a job for t0000-basic.sh
+
+    sed -e "$sanitize_diff_raw" <"$1" >.tmp-1
+    sed -e "$sanitize_diff_raw" <"$2" >.tmp-2
+    diff -u .tmp-1 .tmp-2 && rm -f .tmp-1 .tmp-2
+}
+
+sanitize_diff_raw_z='/^:/s/ '"$_x40"' '"$_x40"' \([A-Z]\)[0-9]*$/ X X \1#/'
+compare_diff_raw_z () {
+    # When heuristics are improved, the score numbers would change.
+    # Ignore them while comparing.
+    # Also we do not check SHA1 hash generation in this test, which
+    # is a job for t0000-basic.sh
+
+    tr '\0' '\012' <"$1" | sed -e "$sanitize_diff_raw_z" >.tmp-1
+    tr '\0' '\012' <"$2" | sed -e "$sanitize_diff_raw_z" >.tmp-2
+    diff -u .tmp-1 .tmp-2 && rm -f .tmp-1 .tmp-2
+}
+
+compare_diff_patch () {
+    # When heuristics are improved, the score numbers would change.
+    # Ignore them while comparing.
+    sed -e '/^[dis]*imilarity index [0-9]*%$/d' <"$1" >.tmp-1
+    sed -e '/^[dis]*imilarity index [0-9]*%$/d' <"$2" >.tmp-2
+    diff -u .tmp-1 .tmp-2 && rm -f .tmp-1 .tmp-2
+}