postcss/test/postcss.test.js

import Processor from '../lib/processor';
import postcss   from '../lib/postcss';

it('creates plugins list', () => {
    let processor = postcss();
    expect(processor instanceof Processor).toBeTruthy();
    expect(processor.plugins).toEqual([]);
});

it('saves plugins list', () => {
    let a = () => 1;
    let b = () => 2;
    expect(postcss(a, b).plugins).toEqual([a, b]);
});

it('saves plugins list as array', () => {
    let a = () => 1;
    let b = () => 2;
    expect(postcss([a, b]).plugins).toEqual([a, b]);
});

it('takes plugin from other processor', () => {
    let a = () => 1;
    let b = () => 2;
    let c = () => 3;
    let other = postcss([a, b]);
    expect(postcss([other, c]).plugins).toEqual([a, b, c]);
});

it('supports injecting additional processors at runtime', () => {
    let plugin1 = postcss.plugin('one', () => {
        return css => {
            css.walkDecls(decl => {
                decl.value = 'world';
            });
        };
    });
    let plugin2 = postcss.plugin('two', () => {
        return (css, result) => {
            result.processor.use(plugin1());
        };
    });

    return postcss([ plugin2 ]).process('a{hello: bob}').then(result => {
        expect(result.css).toEqual('a{hello: world}');
    });
});

it('creates plugin', () => {
    let plugin = postcss.plugin('test', filter => {
        return root => {
            root.walkDecls(filter || 'two', i => i.remove());
        };
    });

    let func1 = postcss(plugin).plugins[0];
    expect(func1.postcssPlugin).toEqual('test');
    expect(func1.postcssVersion).toMatch(/\d+.\d+.\d+/);

    let func2 = postcss(plugin()).plugins[0];
    expect(func2.postcssPlugin).toEqual(func1.postcssPlugin);
    expect(func2.postcssVersion).toEqual(func1.postcssVersion);

    let result1 = postcss(plugin('one')).process('a{ one: 1; two: 2 }');
    expect(result1.css).toEqual('a{ two: 2 }');

    let result2 = postcss(plugin).process('a{ one: 1; two: 2 }');
    expect(result2.css).toEqual('a{ one: 1 }');
});

it('does not call plugin constructor', () => {
    let calls = 0;
    let plugin = postcss.plugin('test', () => {
        calls += 1;
        return () => { };
    });
    expect(calls).toBe(0);

    postcss(plugin).process('a{}');
    expect(calls).toBe(1);

    postcss(plugin()).process('a{}');
    expect(calls).toBe(2);
});

it('creates a shortcut to process css', () => {
    let plugin = postcss.plugin('test', (str = 'bar') => {
        return root => {
            root.walkDecls(i => {
                i.value = str;
            });
        };
    });

    let result1 = plugin.process('a{value:foo}');
    expect(result1.css).toEqual('a{value:bar}');

    let result2 = plugin.process('a{value:foo}', { }, 'baz');
    expect(result2.css).toEqual('a{value:baz}');

    plugin.process('a{value:foo}', { from: 'a' }, 'baz').then( result => {
        expect(result.opts).toEqual({ from: 'a' });
        expect(result.css).toEqual('a{value:baz}');
    });
});

it('contains parser', () => {
    expect(postcss.parse('').type).toEqual('root');
});

it('contains stringifier', () => {
    expect(typeof postcss.stringify).toEqual('function');
});

it('allows to build own CSS', () => {
    let root    = postcss.root({ raws: { after: '\n' } });
    let comment = postcss.comment({ text: 'Example' });
    let media   = postcss.atRule({ name: 'media', params: 'screen' });
    let rule    = postcss.rule({ selector: 'a' });
    let decl    = postcss.decl({ prop: 'color', value: 'black' });

    root.append(comment);
    rule.append(decl);
    media.append(rule);
    root.append(media);

    expect(root.toString()).toEqual('/* Example */\n' +
                                    '@media screen {\n' +
                                    '    a {\n' +
                                    '        color: black\n' +
                                    '    }\n' +
                                    '}\n');
});

it('contains vendor module', () => {
    expect(postcss.vendor.prefix('-moz-tab')).toEqual('-moz-');
});

it('contains list module', () => {
    expect(postcss.list.space('a b')).toEqual(['a', 'b']);
});