Ariadne (TypeScript port)

A TypeScript port of ariadne, a fancy compiler diagnostics & error reporting crate for Rust by Joshua Barretto, licensed under MIT. The renderer is a statement-by-statement port of upstream src/report/write.rs and is verified against the upstream snapshot test suite (see report.spec.ts).

Error: can't compare apples with oranges
   ╭─┤ <unknown>:1:1 │
   │
 1 │ apple == orange;
   │ ──┬──    ───┬──
   │   ╰─────────│──── This is an apple
   │             │
   │             ╰──── This is an orange
───╯

Usage

import { Config, Label, Report } from "@essence-lang/ariadne"

let report = new Report({
	kind: "error",
	span: { start: 0, end: 0 },
	code: "E03",
	message: "can't compare apples with oranges",
	labels: [
		new Label({ start: 0, end: 5 }, { message: "This is an apple" }),
		new Label({ start: 9, end: 15 }, { message: "This is an orange" }),
	],
	helps: ["have you tried peeling the orange?"],
})

console.log(report.render("apple == orange;"))

A code is optional; when given it is printed on its own line above the header, in the same color as Note and Help.

Report.render accepts a plain string, a Source, or — for reports whose labels point into multiple sources — a Cache (see sources()). Labels can be colored individually (ColorGenerator produces distinct colors), ordered, prioritised, and span multiple lines; see LabelOptions and ConfigOptions for everything that can be tuned.

Differences from upstream

• Span offsets are counted in Unicode code points (indexType: "char", the default) or UTF-16 code units (indexType: "utf16"), the JavaScript-native analog of upstream's byte spans.
• The Report/Label/Config builders are replaced with options objects.
• The unstable named-styles feature (Styleable/Config::styles) and the concolor/stream-detection integration are not ported. Terminal color support detection is the caller's responsibility (color: false disables styling, stripAnsi: true additionally strips codes embedded in messages).
• A Report's code sits on its own line above the header, in the note color, rather than sharing the header line and the kind's color.
• Character display widths use a compact approximation of the Unicode East-Asian-width tables rather than the full unicode-width data.

Package extraction

This directory is deliberately self-contained (no imports from the rest of the compiler, no external dependencies, no runtime-specific APIs) so it can be extracted into a standalone package by moving the folder and adding a package.json.