nicegui/tests/test_page.py

import asyncio
from uuid import uuid4

import pytest

from nicegui import Client, task_logger, ui

from .screen import PORT, Screen


def test_page(screen: Screen):
    @ui.page('/')
    def page():
        ui.label('Hello, world!')

    screen.open('/')
    screen.should_contain('NiceGUI')
    screen.should_contain('Hello, world!')


def test_auto_index_page(screen: Screen):
    ui.label('Hello, world!')

    screen.open('/')
    screen.should_contain('NiceGUI')
    screen.should_contain('Hello, world!')


def test_custom_title(screen: Screen):
    @ui.page('/', title='My Custom Title')
    def page():
        ui.label('Hello, world!')

    screen.open('/')
    screen.should_contain('My Custom Title')
    screen.should_contain('Hello, world!')


def test_route_with_custom_path(screen: Screen):
    @ui.page('/test_route')
    def page():
        ui.label('page with custom path')

    screen.open('/test_route')
    screen.should_contain('page with custom path')


def test_auto_index_page_with_link_to_subpage(screen: Screen):
    ui.link('link to subpage', '/subpage')

    @ui.page('/subpage')
    def page():
        ui.label('the subpage')

    screen.open('/')
    screen.click('link to subpage')
    screen.should_contain('the subpage')


def test_link_to_page_by_passing_function(screen: Screen):
    @ui.page('/subpage')
    def page():
        ui.label('the subpage')

    ui.link('link to subpage', page)

    screen.open('/')
    screen.click('link to subpage')
    screen.should_contain('the subpage')


def test_creating_new_page_after_startup(screen: Screen):
    screen.start_server()

    @ui.page('/late_page')
    def page():
        ui.label('page created after startup')

    screen.open('/late_page')
    screen.should_contain('page created after startup')


def test_shared_and_private_pages(screen: Screen):
    @ui.page('/private_page')
    def private_page():
        ui.label(f'private page with uuid {uuid4()}')

    ui.label(f'shared page with uuid {uuid4()}')

    screen.open('/private_page')
    uuid1 = screen.find('private page').text.split()[-1]
    screen.open('/private_page')
    uuid2 = screen.find('private page').text.split()[-1]
    assert uuid1 != uuid2

    screen.open('/')
    uuid1 = screen.find('shared page').text.split()[-1]
    screen.open('/')
    uuid2 = screen.find('shared page').text.split()[-1]
    assert uuid1 == uuid2


def test_wait_for_handshake(screen: Screen):
    async def load() -> None:
        label.text = 'loading...'
        # NOTE we can not use asyncio.create_task() here because we are on a different thread than the NiceGUI event loop
        task_logger.create_task(takes_a_while())

    async def takes_a_while() -> None:
        await asyncio.sleep(0.1)
        label.text = 'delayed data has been loaded'

    @ui.page('/')
    async def page(client: Client):
        global label
        label = ui.label()
        await client.handshake()
        await load()

    screen.open('/')
    screen.should_contain('delayed data has been loaded')


def test_adding_elements_after_handshake(screen: Screen):
    @ui.page('/')
    async def page(client: Client):
        ui.label('before')
        await client.handshake()
        ui.label('after')

    screen.open('/')
    screen.should_contain('before')
    screen.should_contain('after')


@pytest.mark.skip(reason='maybe this causes the timeout on GitHub?')
def test_exception(screen: Screen):
    @ui.page('/')
    def page():
        raise Exception('some exception')

    screen.open('/')
    screen.should_contain('500')
    screen.should_contain('Server error')
    screen.assert_py_logger(
        f'ERROR: unexpected exception for http://localhost:{PORT}/',
        'ERROR: Exception in ASGI application',
    )


def test_exception_after_handshake(screen: Screen):
    @ui.page('/')
    async def page(client: Client):
        await client.handshake()
        ui.label('this is shown')
        raise Exception('some exception')

    screen.open('/')
    screen.should_contain('this is shown')
    screen.assert_py_logger('ERROR: Task raised an exception')


def test_page_with_args(screen: Screen):
    @ui.page('/page/{id}')
    def page(id: int):
        ui.label(f'Page {id}')

    screen.open('/page/42')
    screen.should_contain('Page 42')