core/src/aggregrate-errors.js

"use strict";

const matchVirtualProperty = require("@validatem/match-virtual-property");

const AggregrateValidationError = require("./aggregrate-validation-error");

// TODO: Omit the "At (root)" for path-less errors, to avoid confusion when singular values are being compared?
// TODO: Move out the path generating logic into a separate module, to better support custom error formatting code

module.exports = function aggregrateAndThrowErrors(errors) {
	let rephrasedErrors = errors.map((error) => {
		let stringifiedPathSegments = error.path.map((segment) => {
			if (segment == null) {
				throw new Error(`Unexpected empty path segment encountered; this is a bug, please report it!`);
			} else if (typeof segment === "string") {
				return segment;
			} else if (typeof segment === "number") {
				return String(segment);
			} else if (matchVirtualProperty(segment)) {
				return `(${segment.name})`;
			} else {
				throw new Error(`Unexpected path segment encountered: ${segment}; this is a bug, please report it!`);
			}
		});

		/* TODO: Make immutable */
		let path = (stringifiedPathSegments.length > 0)
			? stringifiedPathSegments.join(" -> ")
			: "(root)";

		error.message = `At ${path}: ${error.message}`;
		return error;
	});

	let detailLines = rephrasedErrors.map((error) => {
		return ` - ${error.message}`;
	}).join("\n");

	if (errors.length > 0) {
		return new AggregrateValidationError(`One or more validation errors occurred:\n${detailLines}`, {
			errors: rephrasedErrors
		});
	}
};