I'm looking to do replacements in unknown third-party inputs in strings that sometimes have quotes among them.
I want to replace a wholeword whereever it occurs unless it's in double or single-quotes, and unless the quote is escaped.
Example: Replacing FOO by BAR
Input:
FOO "FOO" 'FOO' " 1 + FOO + 2 " ABCFOOXYZ " str1\"FOO\"str3'FOO'\'\'" ' str1\'FOOstr3"FOO"\"\"' \"FOO\"
Expected output:
BAR "FOO" 'FOO' " 1 + FOO + 2 " ABCFOOXYZ " str1\"FOO\"str3'FOO'\'\'" ' str1\'FOOstr3"FOO"\"\"' \"BAR\"
More tests:
name: FOO
favoriteQuote: "I am my own FOO."
children: 'FOO\'s children'
cars: ownersList[FOO]
statement = FOO + " is the owner of the house."
Expected output:
name: BAR
favoriteQuote: "I am my own FOO."
children: 'FOO\'s children'
cars: ownersList[BAR]
statement = BAR + " is the owner of the house."
I saw this question: Match and replace a word not in quotes (string contains escaped quotes) which I thought was similar and could be a good starting point the accepted answer does not work at all:
https://regex101.com/r/Lfan64/5
If anyone could help me get the expected result from my regex that would be great, thanks.
If I am understanding your requirements correctly, you may try this regex for your cases:
((['"])(?:\\.|(?!\2).)*(?<!\\)\2)|\bFOO\b/g
This regex uses alternation to match and discard what we need to keep on LHS of | whereas on RHS we match whatever we want to replace in the result.
Code:
const str = String.raw`name: FOO
favoriteQuote: "I am my own FOO."
children: 'FOO\'s children'
cars: ownersList[FOO]
statement = FOO + " is the owner of the house."
FOO "FOO" 'FOO' " 1 + FOO + 2 " ABCFOOXYZ " str1\"FOO\"str3'FOO'\'\'" ' str1\'FOOstr3"FOO"\"\"' \"FOO\"`;
var repl = str.replace(/((['"])(?:\\.|(?!\2).)*(?<!\\)\2)|\bFOO\b/g,
(_, g) => g || "BAR");
console.log(repl); RegEx Details:
(: Start capture group #1
(['"]): Match ' or " in capture group #2(?:\\.|(?!\2).)*: Match an escaped character or any character except the quote we matched in capture group #2(?<!\\)\2: Match whatever quote we matched in capture group #2 as long as it is not preceded by a \): End capture group #1|: OR\bFOO\b: Match complete word FOOYou can use
const text = String.raw`name: FOO
favoriteQuote: "I am my own FOO."
children: 'FOO\'s children'
cars: ownersList[FOO]
statement = FOO + " is the owner of the house."
FOO "FOO" 'FOO' " 1 + FOO + 2 " ABCFOOXYZ " str1\"FOO\"str3'FOO'\'\'" ' str1\'FOOstr3"FOO"\"\"' \"FOO\"`
console.log( text.replace(
/((?:[^\\]|^)(?:\\{2})*(?:"[^"\\]*(?:\\[^][^"\\]*)*"|'[^'\\]*(?:\\[^][^'\\]*)*'))|FOO/g,
(match, group) => group || "BAR"
))Details:
((?:[^\\]|^)(?:\\{2})*(?:"[^"\\]*(?:\\[^][^"\\]*)*"|'[^'\\]*(?:\\[^][^'\\]*)*')) - Group 1:
(?:[^\\]|^) - a char other than \ or start of string(?:\\{2})* - zero or more sequences of double backslash(?:"[^"\\]*(?:\\[^][^"\\]*)*"|'[^'\\]*(?:\\[^][^'\\]*)*') - either of a double or single quoted string literal pattern with escape sequence support| - orFOO - a FOO string in any other context.The (match, group) => group || "BAR" replacement means that if Group 1 matches, the replacement is Group 1 value, else, the replacement is BAR.