Git Replace

.bashrc

# --------------------------------------------------------------------
# 1st parameter: regex search string
# - if you wanna match brackets (, ), [, ] you need to escape them
# - otherwise they are handled as capture groups and character classes
# 2nd parameter: regex replace string (can be empty as well)
# - don't escape anything
# - back references to the first 3 capture groups can be used here: \1, \2 and \3
# --------------------------------------------------------------------

function gitreplace() {
	if [ -z "$1" ]; then
		echo "No pattern given!"
		echo
		echo "Examples:"
		echo "gitreplace 'something old' 'nice and new'"
		echo "gitreplace 'something really old' DROP/DROP+1/DROP+2/..."
		echo "gitreplace 'old' 'new' <target>"
		echo
		echo "__BOL__ and __EOL__ can be used to match beginning and end of line!"
		return
	fi

	search="$1"
	replace="$2"
	if [ -z "$3" ]; then
		target="."
	else
		target="$3"
	fi

	# -----------------------
	# Escape search parameter
	# -----------------------

	# Substitute escaped characters by temporary tokens
	search="${search/\\\[/__SQUARE_OPEN__}"
	search="${search/\\\]/__SQUARE_CLOSE__}"
	search="${search/\\\(/__ROUND_OPEN__}"
	search="${search/\\\)/__ROUND_CLOSE__}"
	search="${search/\\\$/__DOLLAR__}"
	search="${search/\\\./__DOT__}"

	# Escape backslashes & slashes
	search="${search//\\/\\\\}"
	search="${search//\//\\/}"

	# Re-substitute temporary tokens back to escape characters
	search="${search/__SQUARE_OPEN__/\\\[}"
	search="${search/__SQUARE_CLOSE__/\\\]}"
	search="${search/__ROUND_OPEN__/\\\(}"
	search="${search/__ROUND_CLOSE__/\\\)}"
	search="${search/__DOLLAR__/\\\$}"
	search="${search/__DOT__/\\\.}"

	# Replace magic tokens
	search="${search/__BOL__/\^}"
	search="${search/__EOL__/\$}"
	# --------------------------------------
	# Find matching text files of repository
	# --------------------------------------

	# -l Instead of showing every matched line, show only the names of files that contain matches
	# -I Don’t match the pattern in binary files
	# -E extended regex
	#echo git grep -l -I -E \""$search"\" -- "$target"
	files=$(git grep -l -I -E "$search" -- "$target")
	if [ -z "$files" ]; then
		echo "No files found matching pattern '$search'!"
		echo
		echo "Hint: literal brackets have to be escaped!"
		return
	#else
	#	echo "Files: $files"
	fi

	# ------------------------
	# Escape replace parameter
	# ------------------------

	# Substitute capture group back references by temporary tokens
	replace="${replace//\\1/__REFERENCE_1__}"
	replace="${replace//\\2/__REFERENCE_2__}"
	replace="${replace//\\3/__REFERENCE_3__}"

	# Escape backslashes & slashes
	replace="${replace//\\/\\\\}"
	replace="${replace//\//\\/}"

	# Re-substitute temporary tokens back to capture group back references
	replace="${replace//__REFERENCE_1__/\\1}"
	replace="${replace//__REFERENCE_2__/\\2}"
	replace="${replace//__REFERENCE_3__/\\3}"

	# -----------------------
	# Perform the replacement
	# -----------------------

	# -r extended regex
	# Matching line should be simply dropped:
	if [[ "$replace" == DROP* ]]; then
		lines=${replace/DROP+/}
		lines=$((lines)) # cast to integer
		echo "$files" | while IFS= read -r file; do
			sed -r -i "/$search/,+${lines}d" -- "$file"
		done
	else
		echo "$files" | while IFS= read -r file; do
			sed -r -i "s/$search/$replace/g" -- "$file"
		done
	fi
}