Musubi (結び, meaning "connection" in Japanese) is a high-performance diagnostics renderer crafted to enhance the presentation of compiler errors and warnings across multiple programming languages. Drawing inspiration from Rust's Ariadne library, Musubi elevates diagnostic messaging with beautiful color-coding, precise source location highlighting, multi-line spans, and intelligent label clustering.

Overview

Musubi stands out for its capability to produce aesthetically pleasing output while ensuring high performance:

• C Library: Features a high-performance core complemented by Lua bindings (musubi.h, musubi.c).
• Rust Crate: Offers a safe FFI wrapper with an ergonomic builder API (musubi-rs).

Both the C and Rust implementations provide identical rendering output and are complemented by extensive testing efforts, including 100% test coverage for robust reliability.

Key Features

• Visually Appealing Output: Multi-line diagnostics with color-coded labels for easier interpretation, intelligent clustering of labels, and support for both Unicode and CJK characters.
• Optimized Performance: Reduced rendering complexity from O(n²) to O(n) through techniques like pre-computed width caching for UTF-8 strings and efficient line windowing calculations.
• Production-Ready Implementation: 100% test coverage with memory-safe implementations across Rust and C, comprehensive error handling measures, and compatibility with Lua 5.1, 5.4, and LuaJIT.

Example Usage

local mu = require "musubi"
local cg = mu.colorgen()

print(
    mu.report("Error", "Incompatible types")
    :code "3"
    :label(33, 33):message("This is of type Nat"):color(cg:next())
    :label(43, 45):message("This is of type Str"):color(cg:next())
    :label(12, 48):primary():message("These values are outputs of this match expression"):color(cg:next())
    :note "Outputs of match expressions must coerce to the same type"
    :source([[
def five = match () in {
	() => 5,
	() => "5",
}

def six = five + 1
]], "sample.tao")
    :render())

In this example, the renderer highlights the precise nature of the compiler diagnostics, providing clear visual cues that make debugging simpler and more efficient.

Conclusion

Musubi offers a compelling solution for developers seeking improved compiler diagnostics across programming languages. Through its elegant output styling and high-performance rendering capabilities, it facilitates a more intuitive debugging experience.