searcher.js: Escape characters when building regexps

[byroot]

Otherwise characters with regexp meaning like . won't behave as expected.

Actually . when inside [] doesn't have a special meaning, however \ and a few other break the search.

[matzbot]

🚀 Preview deployment available at: https://6621dea1.rdoc-6cd.pages.dev (commit: 481b5d5)

[st0012]

Sorry can you give me an example of the issue that you're trying to fix?

[byroot]

For now this doesn't fix much of anything, because nothing really match these special characters.

But my initial plan was to allow to search by fully qualified name, e.g. Array#map, or Array.new, and this small bug was in the way. I didn't get around to implement the feature I wanted (yet?) because the JSON blob with the data that is being searched doesn't have fully qualified names. So it's much more work.

Hence I figured I'd just submit that small fix independently.

If you want to check it works, go on the current version of RDoc, and search for \:

Uncaught SyntaxError: unterminated character class
    buildRegexps https://ruby.github.io/rdoc/js/searcher.js:61
    buildRegexps https://ruby.github.io/rdoc/js/searcher.js:60
    find https://ruby.github.io/rdoc/js/searcher.js:17
    search https://ruby.github.io/rdoc/js/search.js:54
    observer https://ruby.github.io/rdoc/js/search.js:23
2 [searcher.js:61:14](https://ruby.github.io/rdoc/js/searcher.js)

On this branch, it doesn't crash.

[st0012]

Ah ok I can verify that it avoids the JS error. Thanks!

[glaszig]

quote mdn:

Since ⁨May 2025⁩, this feature works across the latest devices and browser versions.

and that's why search broke in safari 17.6:

TypeError: RegExp.escape is not a function. (In 'RegExp.escape(query[i])', 'RegExp.escape' is undefined) in searcher.js:63

i don't think only and exclusively browsers from 2025 should be required for a documentation page.

would you accept an alternative implementation even if it means "bundling" a polyfill?

i think even this should work for the purpose:

if (!RegExp.escape) {
    RegExp.escape = function(string) {
        return string.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
    };
}

[byroot]

i don't think only and exclusively browsers from 2025 should be required for a documentation page.

Why the snark?

Of course it's an oversight, and of course a fix is welcome. It never occurred to me Regexp.escape might be a new thing, sorry my JS is rusty.

I'll be looking for a polyfill.

[byroot]

#1442