plug-script/test/unit/psc.test.js

A toy programming language

'use strict';

var expect = require('chai').expect,
    _ = require('lodash'),
    path = require('path'),
    fs = require('fs'),
    psc = require('../..');

describe('psc', function() {

    describe('successfully', function() {

        // Instead of making assertions about exactly what the output js will be,
        // it would be nice to just run it and ensure that the results are equivalent
        // to what we expect. It would also be nice to lint the generated js.

        function prefixWithUseStrict(code) {
            return '"use strict";\n\nmodule.exports = ' + code;
        }

        it('compiles simple addition', function() {
            return expect(psc({code: '1 + 2'})).to.equal(prefixWithUseStrict('1 + 2;'));
        });

        it('compiles simple subtraction', function() {
            return expect(psc({code: '1 - 2'})).to.equal(prefixWithUseStrict('1 - 2;'));
        });

        it('compiles a function call', function() {
            return expect(psc({code: 'fib n'})).to.equal(prefixWithUseStrict('fib(n);'));
        });

        it('compiles a conditional', function() {
            return expect(psc({code: 'if 3 <= 5 then 1 else 0'})).to.equal(prefixWithUseStrict('(3 <= 5) ? (1) : (0);'));
        });

        it('compiles a function declaration', function() {
            return expect(psc({code: 'fun fib n -> n + 1'})).to.equal(prefixWithUseStrict('function fib(n) {return n + 1;};'));
        });

        it('compiles two func applications', function() {
            return expect(psc({code: '(sum x) + (sum y)'})).to.equal(prefixWithUseStrict('(sum(x)) + (sum(y));'));
        });

        it('compiles fib', function() {
            var fibFilePath = path.join(__dirname, '..', 'fixtures', 'fib.pluggie');
            return expect(psc({file: fibFilePath})).to.equal(
                prefixWithUseStrict('function fib(n) {return (n <= 1) ? (1) : ((fib(n - 1)) + (fib(n - 2)));};')
            );
        });

    });

    describe('failure', function() {

        it('does not allow a method to have a name that is an expression', function() {
            expect(function() {
                psc({code: 'fun fib 1 + 2 -> 4'});
            }).to.throw(/parse error/i);
        });

    });


});