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regexbashgrepescapinguser-input

Stop escaping forward slash in bash variables

I am having trouble with expanding variables and ignoring their forward slashes.

I have written a simple script that finds text in my git repository and replaces it with other text. This works fine, but now I want to expand it using regex. This shouldn't be too much of a problem since both git grep and sed support regex. However, when I try to use regex in my input variables the forward slashes are removed which ruins the script.

If I run git grep "\bPoint" in the terminal I will get many results. However, I can't figure out how to get the same results when I use user input in my script. The git grep file will change my input to bPoint instead of \bPoint, and won't find any results to give to sed.

#!/bin/bash

# This script allows you to replace text in the git repository without damaging
# .git files. 

read -p "Text to replace: " toReplace
read -p "Replace with: " replaceWith

git grep -l ${toReplace}

# The command I want to run
#git grep -l "${toReplace}" | xargs sed -i "s,${toReplace},${replaceWith},g"

I've tried a lot of different combinations of quotations, but nothing seems to work for me.

Solution

  • You must use read -r. As per help read:

    -r do not allow backslashes to escape any characters

    Examples:

    # without -r
read -p "Text to replace: " toReplace && echo "$toReplace"
Text to replace: \bPoint
bPoint

# with -r
read -rp "Text to replace: " toReplace && echo "$toReplace"
Text to replace: \bPoint
\bPoint