@parcel/codeframe

This package is a small utility extracted from Parcel that generates formatted code frames for error messages - the kind that shows your code with line numbers and highlights where the error occurred. Despite the description mentioning bundling, this is purely a formatting library with zero runtime overhead or resource concerns.

In production, it's been rock-solid. The API is dead simple: pass in your source code, location info, and get back a nicely formatted string. No configuration needed, no state to manage, no connections to pool. Memory footprint is negligible since it just does string manipulation. Performance is excellent - formatting happens in microseconds even for large files.

The main gotcha is that it's a presentation layer tool, not a bundler itself. If you're looking for Parcel the bundler, that's a different package. This shines in CLI tools, build plugins, or any tooling where you need to display user-friendly error messages with code context. Error handling is straightforward - if you pass invalid input, it fails fast with clear messages.

This is actually a focused utility library extracted from Parcel's core, not the bundler itself. It generates pretty, syntax-highlighted code frames for displaying errors with context—think the kind of output you see when Babel or ESLint shows you where something went wrong. The API is straightforward: pass in source code, location info, and get back a nicely formatted string with line numbers and highlighting.

The TypeScript definitions are clean and the main function signature is intuitive. You get terminal color support out of the box with proper ANSI codes. Error messages are minimal since the library itself is quite simple—it either works or you've passed invalid input. The main gotcha is understanding that this is a low-level primitive; you need to handle source maps and position mapping yourself if working with transformed code.

Documentation is sparse but the package is simple enough that reading the TypeScript definitions tells you everything you need. It does one thing well without unnecessary abstractions. Perfect for building developer tools, CLI error reporters, or custom bundler/transpiler output.

The @parcel/codeframe package is a focused utility for generating formatted code snippets with error highlighting, primarily extracted from Parcel's bundler. In production, it's lightweight and does exactly what it says - takes source code and location info, returns a nicely formatted string with syntax highlighting and error context. Memory footprint is negligible, and there's no connection pooling or async behavior to worry about since it's purely synchronous string formatting.

The API is straightforward: pass in your code string, line/column numbers, and optional highlighting. Performance is excellent even with large source files - it only processes the relevant lines plus context. Error handling is minimal since the function is simple, though it doesn't gracefully handle edge cases like invalid line numbers (returns empty string). No logging hooks or observability built in, which is fine for a utility this focused.

Configuration is barebones - you get what you get in terms of formatting style. No timeout concerns since it's sync. Breaking changes between Parcel versions can affect this package, but the API surface is small enough that impact is usually minimal. Works reliably under load in CLI tools and build systems where we've used it for error reporting.