/**
 * Tests error chaining
 *
 *  Copyright (C) 2010-2019 R-T Specialty, LLC.
 *
 *  This file is part of the Liza Data Collection Framework.
 *
 *  liza is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as
 *  published by the Free Software Foundation, either version 3 of the
 *  License, or (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import * as sut from "../../src/error/ChainedError";
import { expect } from 'chai';


describe( 'ChainedError', () =>
{
    it( "can be created with generic error", () =>
    {
        const eprev = new Error( "previous error" );

        expect( sut.chain( new Error( "new error" ), eprev ).chain )
            .to.equal( eprev );
    } );


    it( "can be chained to arbitrary depth", () =>
    {
        const e1 = new Error( "lower" );
        const e2 = sut.chain( new Error( "mid" ), e1 );
        const e3 = sut.chain( new Error( "outer" ), e2 );

        expect( sut.isChained( e3 ) ).to.be.true;
        expect( sut.isChained( e2 ) ).to.be.true;
        expect( sut.isChained( e1 ) ).to.be.false;
    } );


    it( "provides type predicate for TypeScript", () =>
    {
        const inner = new Error( "inner" );

        // force to Error to discard ChainedError type
        const outer: Error = sut.chain( new Error( "outer" ), inner );

        if ( sut.isChained( outer ) )
        {
            // if isChained was properly defined, then outer should now
            // have type ChainedError, and so this should compile
            expect( outer.chain ).to.equal( inner );
        }
        else
        {
            expect.fail();
        }
    } );
} );