JSLint VS SensioLabs Insight

UPDATE 8/22/2011: found http://jshint.com, it looks much better than http://jslint.com/. Source: about 2 years ago

Use https://jslint.com to find the unescaped quote or whatever that's invalidating the file. Remember to put quote marks in dialogue as \". Source: over 2 years ago

Ooh! I'm pretty sure I actually know this one! I watched a bunch of Douglas Crockford talk's at Yahoo! Talking about the weirdness of the language he helped develop (such as this one). He also has built JSLint to help pull out code that runs but can have unexpected results. Booleans in JS evaluate if something is truthy or falsy and undefined is falsy (19:20), however a string of "undefined" would be truthy, and... Source: over 2 years ago

For future, just pop your code into an HTML Validator, a JS Linter, or a CSS Linter and it will check for basic stuff like this. There are also plugins in most IDEs for these kind of things which are incredibly useful. Source: about 3 years ago

Automate as much review things as possible, i.e. Use a static analyser (e.g. PHPStan or Psalm) and a code style fixer (e.g. PHP CS Fixer of PHPCS) and enforce it through CI/CD. Optionally, extend this with some very specific static analysis tools like https://insight.symfony.com/. Source: over 1 year ago

You can use their commercial products like Symfony Insight, attend official Symfony conferences, buy the Symfony book, or if you are rich or own a company, sponsor them. - Source: dev.to / over 1 year ago