From a09f31f9d39c3b16f67463f7a88f8ab917f5284f Mon Sep 17 00:00:00 2001
From: Nathan Broadbent <nathan.f77@gmail.com>
Date: Sat, 10 Dec 2011 16:33:50 +0800
Subject: [PATCH] Added git bisect wrapper to find commit that removed text

---
 lib/git/tools.sh | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/lib/git/tools.sh b/lib/git/tools.sh
index 767b988..15aed51 100644
--- a/lib/git/tools.sh
+++ b/lib/git/tools.sh
@@ -53,3 +53,25 @@ git_ignore() {
 git_exclude() {
   git_ignore "$1" ".git/info/exclude"
 }
+
+
+# Use git bisect to find where text was removed from a file.
+#
+# Example:
+#
+# - Locate the commit where the text "strawberry" was removed from the file 'FRUITS'.
+#   - The text was not present in 992048f
+#
+#  git_bisect_grep 992048f "strawberry" FRUITS
+#
+git_bisect_grep() {
+  if [ -z "$2" ]; then
+    echo "Usage: git_bisect_grep <good_revision> <string>";
+    exit 1
+  fi
+  if [ -n "$3" ]; then search_path="$3"; else search_path="."; fi
+  git bisect start
+  git bisect good $1
+  git bisect bad
+  git bisect run grep -qvRE "$2" $search_path
+}