JavaScript Formatter & Comment Stripper

JavaScript is a full programming language, and that is precisely why a genuinely correct formatter or minifier for it is hard to build — tools like Prettier (formatting) and Terser (minification) work by parsing JavaScript into a complete abstract syntax tree (AST), understanding every language construct (arrow functions, destructuring, generators, optional chaining, template literals, regular expressions, and so on), and then regenerating code from that tree. Building a real JS parser is a multi-year engineering effort, not something to hand-roll for a browser widget, and this tool does not attempt it. Instead, this tool implements something much more modest and much safer: a brace-depth-based re-indenter for Format, and a comment-stripper plus whitespace-collapser for Minify — neither of which requires actually understanding JavaScript grammar, only correctly recognising where string literals, template literals, regular expressions and comments begin and end (so that a brace or a // inside a string doesn't get mistaken for real code). Format walks the source character by character, tracking nesting depth via {, [ and ( characters, and re-indents each line based on that depth — it does not rearrange, rewrite, or restructure your code in any way, it only adjusts leading whitespace. Minify strips // line comments and /* */ block comments, then removes blank lines and trims trailing whitespace from each line, without touching the code itself. The critical engineering detail in both modes is correctly skipping over content that merely *looks* like code but is not: a { character inside a string literal ("an object looks like { this }"), a // inside a template literal, or a /* inside a regular expression literal (/\/\*/ is a valid regex matching the literal text "/*") must never be treated as real syntax. This tool's tokenizer specifically tracks whether it is currently inside a single-quoted string, double-quoted string, template literal (including keeping template literal ${...} interpolation braces correctly balanced against the outer brace count), a line comment, a block comment, or plausibly a regex literal, and only counts braces/parses comments when none of those apply. Getting this wrong is the single most common way a naive "strip comments with a regex" script corrupts real-world JavaScript — removing what looks like a comment start inside a string, or miscounting brace depth because of an object literal string — so this is treated as the correctness-critical part of the implementation, not an afterthought. This is explicitly a lightweight, readability-focused formatter, not an AST-based tool, and it is honest about that limitation: it will not fix inconsistent code style beyond indentation (it will not add missing semicolons, normalize quote style, wrap long lines, or reformat multi-line expressions the way Prettier's line-width-aware algorithm does), and it will not catch or fix ASI (automatic semicolon insertion) hazards — JavaScript code that relies on subtle line-break-dependent parsing behaviour is passed through with its original line structure mostly intact, since this tool never merges or splits statements, only re-indents existing lines. For anything going into a real codebase, use Prettier (formatting) or ESLint (linting) — both understand JavaScript's actual grammar and will do a categorically better and safer job. This tool is aimed at quick readability fixes on a pasted snippet: unminifying a squashed one-liner enough to read it, or cleaning up copy-pasted code with inconsistent indentation, without needing to install anything.