react-document-meta/lib/__tests__/basic.test.js

Declarative, nested and stateful HTML document meta tags for React

import assert from 'assert';
import React from 'react';
import { renderToStaticMarkup } from 'react-dom/server';
import DocumentMeta from '../';
import DocumentMetaServer from '../server';

describe('DocumentMeta', () => {
  beforeAll(() => {
    DocumentMeta.canUseDOM = false;
  });

  describe('.rewind()', () => {
    it('clears the mounted instances', () => {
      renderToStaticMarkup(
        React.createElement(
          DocumentMeta,
          { title: 'a' },
          React.createElement(
            DocumentMeta,
            { title: 'b' },
            React.createElement(DocumentMeta, { title: 'c' })
          )
        )
      );
      assert.deepEqual(DocumentMeta.peek(), { title: 'c' });
      DocumentMeta.rewind();
      assert.strictEqual(DocumentMeta.peek(), undefined);
    });

    it('returns the latest document meta', () => {
      const title = 'cheese';
      renderToStaticMarkup(
        React.createElement(
          DocumentMeta,
          { title: 'a' },
          React.createElement(
            DocumentMeta,
            { title: 'b' },
            React.createElement(DocumentMeta, { title })
          )
        )
      );
      assert.deepEqual(DocumentMeta.rewind(), { title });
    });

    it('returns undefined if no mounted instances exist', () => {
      renderToStaticMarkup(
        React.createElement(
          DocumentMeta,
          { title: 'a' },
          React.createElement(
            DocumentMeta,
            { title: 'b' },
            React.createElement(DocumentMeta, { title: 'c' })
          )
        )
      );
      DocumentMeta.rewind();
      assert.strictEqual(DocumentMeta.peek(), undefined);
    });
  });

  describe('.renderAsReact()', () => {
    it('returns an empty array if no meta data has been mounted', () => {
      React.createElement(
        DocumentMeta,
        { title: 'a' },
        React.createElement(
          DocumentMeta,
          { title: 'b' },
          React.createElement(DocumentMeta, { title: 'c' })
        )
      );

      const rendered = DocumentMeta.renderAsReact();
      assert.ok(Array.isArray(rendered));
      assert.strictEqual(rendered.length, 0);
    });

    it('returns the latest document meta as an array of React components', () => {
      renderToStaticMarkup(
        React.createElement(
          DocumentMeta,
          { title: 'a' },
          React.createElement(
            DocumentMeta,
            { title: 'b' },
            React.createElement(DocumentMeta, { title: 'c' })
          )
        )
      );

      const rendered = DocumentMeta.renderAsReact();
      assert.ok(Array.isArray(rendered));
      assert.strictEqual(rendered.length, 1);
      assert.strictEqual(rendered[0].type, 'title');
      assert.strictEqual(rendered[0].props.children, 'c');
    });
  });

  describe('container element with children', () => {
    it('renders the child', () => {
      const title = 'foo';
      const markup = renderToStaticMarkup(
        <DocumentMeta title={title}>
          <div>Child element</div>
        </DocumentMeta>
      );

      assert.strictEqual(markup, '<div>Child element</div>');
      assert.deepEqual(DocumentMeta.rewind(), { title });
    });
    it('renders the children, wrapped in a div if more than one child', () => {
      const title = 'foo';
      const markup = renderToStaticMarkup(
        <DocumentMeta title={title}>
          <div>foo</div>
          <div>bar</div>
        </DocumentMeta>
      );

      assert.strictEqual(markup, '<div><div>foo</div><div>bar</div></div>');
      assert.deepEqual(DocumentMeta.rewind(), { title });
    });
  });
});

describe('DocumentMetaServer', () => {
  describe('.renderToStaticMarkup()', () => {
    it('returns an empty string if no meta data has been mounted', () => {
      React.createElement(
        DocumentMeta,
        { title: 'a' },
        React.createElement(
          DocumentMeta,
          { title: 'b' },
          React.createElement(DocumentMeta, { title: 'c' })
        )
      );
      assert.strictEqual(DocumentMetaServer.renderToStaticMarkup(), '');
    });

    it('returns the latest document meta as HTML', () => {
      renderToStaticMarkup(
        React.createElement(
          DocumentMeta,
          { title: 'a' },
          React.createElement(
            DocumentMeta,
            { title: 'b' },
            React.createElement(DocumentMeta, { title: 'c' })
          )
        )
      );
      assert.strictEqual(
        DocumentMetaServer.renderToStaticMarkup(),
        '<title>c</title>'
      );
    });
  });

  describe('.renderAsHTML()', () => {
    it('returns an empty string if no meta data has been mounted', () => {
      React.createElement(
        DocumentMeta,
        { title: 'a' },
        React.createElement(
          DocumentMeta,
          { title: 'b' },
          React.createElement(DocumentMeta, { title: 'c' })
        )
      );
      assert.strictEqual(DocumentMetaServer.renderAsHTML(), '');
    });

    it('returns the latest document meta as HTML', () => {
      renderToStaticMarkup(
        React.createElement(
          DocumentMeta,
          { title: 'a' },
          React.createElement(
            DocumentMeta,
            { title: 'b' },
            React.createElement(DocumentMeta, { title: 'c' })
          )
        )
      );
      assert.strictEqual(DocumentMetaServer.renderAsHTML(), '<title>c</title>');
    });
  });
});