pythonnative/tests/test_hosts.py at main · pythonnative/pythonnative · GitHub

Repository navigation

History

412 lines (319 loc) · 14.6 KB

Raw

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

278

279

280

281

282

283

284

285

286

287

288

289

290

291

292

293

294

295

296

297

298

299

300

301

302

303

304

305

306

307

308

309

310

311

312

313

314

315

316

317

318

319

320

321

322

323

324

325

326

327

328

329

330

331

332

333

334

335

336

337

338

339

340

341

342

343

344

345

346

347

348

349

350

351

352

353

354

355

356

357

358

359

360

361

362

363

364

365

366

367

368

369

370

371

372

373

374

375

376

377

378

379

380

381

382

383

384

385

386

387

388

389

390

391

392

393

394

395

396

397

398

399

400

401

402

403

404

405

406

407

408

409

410

411

412

"""Tests for screen-host lifecycle behavior (``pythonnative.hosts``).

Off-device the host class is the headless ``ScreenHost``; these tests

drive it against a ``FakeBackend`` installed as the process registry.

The on-device host is covered by ``test_bridge.py`` through a

``FakeTransport``.

"""

import os

import sys

import types

from pathlib import Path

from typing import Any, Iterator, List, Optional, cast

import pytest

from pythonnative import diagnostics

from pythonnative.bridge import set_transport

from pythonnative.bridge.fake import FakeTransport

from pythonnative.component import component

from pythonnative.element import Element

from pythonnative.hooks import use_back_handler, use_effect, use_state

from pythonnative.hosts import create_screen, import_component

from pythonnative.native_views import set_backend

from pythonnative.testing import FakeBackend, FakeView, settle

@pytest.fixture

def backend(monkeypatch: pytest.MonkeyPatch) -> Iterator[FakeBackend]:

"""Install a ``FakeBackend`` as the registry the host mounts into."""

fake = FakeBackend()

set_backend(fake)

transport = FakeTransport()

set_transport(transport)

from pythonnative.bridge import codec

from pythonnative.hosts.base import ScreenHost

monkeypatch.setattr(

ScreenHost,

"_show_error",

lambda self, payload: transport.call("Host", "show_error", codec.dumps({"call_id": 0, "args": payload})),

)

monkeypatch.setattr(

ScreenHost,

"_dismiss_error",

lambda self: transport.call("Host", "dismiss_error", codec.dumps({"call_id": 0, "args": {}})),

)

try:

yield fake

finally:

set_backend(None)

set_transport(None)

def _install_app_module(monkeypatch: pytest.MonkeyPatch, name: str, root: Any) -> str:

"""Register an in-memory module exposing ``root`` as its ``App``."""

module = types.ModuleType(name)

module.App = root # type: ignore[attr-defined]

monkeypatch.setitem(sys.modules, name, module)

return name

def _text_of(view: Optional[FakeView]) -> List[str]:

return [v.text for v in view.walk() if v.text is not None] if view is not None else []

def _write_screen(path: Path, text: str) -> None:

path.write_text(

"from pythonnative.component import component\n"

"from pythonnative.element import Element\n\n"

"@component\n"

"def MainPage():\n"

f" return Element('Text', {{'text': {text!r}}}, [])\n",

encoding="utf-8",

)

# ======================================================================

# Hot reload

# ======================================================================

def test_screen_reload_reimports_root_component(

tmp_path: Path,

monkeypatch: pytest.MonkeyPatch,

backend: FakeBackend,

) -> None:

package_dir = tmp_path / "reload_app"

package_dir.mkdir()

screen_path = package_dir / "screen.py"

_write_screen(screen_path, "before")

monkeypatch.syspath_prepend(os.fspath(tmp_path))

monkeypatch.setattr(sys, "dont_write_bytecode", True)

sys.modules.pop("reload_app.screen", None)

sys.modules.pop("reload_app", None)

host = create_screen("reload_app.screen.MainPage")

host.on_create()

assert _text_of(host.root_native_view) == ["before"]

_write_screen(screen_path, "after")

host.reload(["reload_app.screen"])

assert _text_of(host.root_native_view) == ["after"]

host.on_destroy()

# ======================================================================

# Lifecycle

# ======================================================================

def test_screen_host_on_destroy_unmounts_tree(monkeypatch: pytest.MonkeyPatch, backend: FakeBackend) -> None:

"""``on_destroy`` must unmount the reconciler: cleanups run, views die."""

cleanups: list = []

@component

def Root() -> Element:

use_effect(lambda: lambda: cleanups.append("cleaned"), [])

return Element("Text", {"text": "hi"}, [])

host = create_screen(_install_app_module(monkeypatch, "destroy_app", Root))

host.on_create()

assert host.reconciler is not None

assert backend.live_view_count() > 0

assert cleanups == []

host.on_destroy()

assert cleanups == ["cleaned"], "effect cleanup must run on destroy"

assert host.reconciler is None

assert host.root_native_view is None

assert backend.live_view_count() == 0

def test_screen_host_on_create_is_idempotent_across_view_recreation(

monkeypatch: pytest.MonkeyPatch, backend: FakeBackend

) -> None:

"""Android recreates a fragment's view on pop-back; the tree must persist."""

mounts: list = []

@component

def Root() -> Element:

use_effect(lambda: mounts.append("mounted"), [])

return Element("Text", {"text": "hi"}, [])

host = create_screen(_install_app_module(monkeypatch, "recreate_app", Root))

host.on_create()

reconciler, root = host.reconciler, host.root_native_view

host.on_create()

assert host.reconciler is reconciler

assert host.root_native_view is root

assert mounts == ["mounted"]

host.on_destroy()

def test_screen_host_focus_and_args(monkeypatch: pytest.MonkeyPatch, backend: FakeBackend) -> None:

"""``on_pause`` / ``on_resume`` drive focus listeners; ``set_args`` accepts JSON."""

@component

def Root() -> Element:

return Element("Text", {"text": "hi"}, [])

host = create_screen(_install_app_module(monkeypatch, "focus_app", Root), None, '{"pn_nav": {"routes": []}}')

assert host.args == {"pn_nav": {"routes": []}}

assert host.initial_navigation_state() is None, "an empty route list is not a navigation state"

host.set_args("not json")

assert host.args == {}

host.set_args({"k": 1})

assert host.args == {"k": 1}

seen: List[bool] = []

remove = host.add_focus_listener(seen.append)

host.on_create()

assert host.is_focused is True

host.on_pause()

host.on_resume()

assert seen == [False, True], "focus listeners fire once per transition"

remove()

host.on_pause()

assert seen == [False, True]

host.on_destroy()

def test_screen_host_on_back_pressed_routes_to_handlers(monkeypatch: pytest.MonkeyPatch, backend: FakeBackend) -> None:

"""``on_back_pressed`` consults ``use_back_handler`` subscribers."""

consume = {"value": True}

@component

def Root() -> Element:

_count, _set_count = use_state(0)

use_back_handler(lambda: consume["value"])

return Element("Text", {"text": "hi"}, [])

host = create_screen(_install_app_module(monkeypatch, "back_app", Root))

host.on_create()

assert host.on_back_pressed() is True

consume["value"] = False

assert host.on_back_pressed() is False

host.on_destroy()

assert host.on_back_pressed() is False, "destroyed host must decline back events"

# ======================================================================

# Viewport

# ======================================================================

def test_set_viewport_size_forwards_to_reconciler(monkeypatch: pytest.MonkeyPatch, backend: FakeBackend) -> None:

@component

def Root() -> Element:

return Element("Column", {}, [Element("Text", {"text": "hi"}, [])])

host = create_screen(_install_app_module(monkeypatch, "viewport_app", Root))

host.set_viewport_size(390, 844) # before mount: nothing to forward to

host.on_create()

assert host.reconciler is not None

assert backend.ops_of("set_frame") == [], "the headless host supplies no viewport, so no layout yet"

host.set_viewport_size(390, 844)

assert host.reconciler.viewport_size == (390.0, 844.0)

# The root's own frame is owned by the platform host; children get laid out to the viewport width.

text = host.root_native_view.find_first("Text")

assert text is not None and text.frame[2] == 390.0

host.set_viewport_size(0, 844)

assert host.reconciler.viewport_size == (390.0, 844.0), "non-positive sizes are ignored"

host.on_destroy()

@pytest.fixture

def _metrics() -> Iterator[None]:

from pythonnative import platform_metrics

def reset() -> None:

platform_metrics.reset_window_dimensions()

platform_metrics.reset_screen_dimensions()

platform_metrics.reset_keyboard_height()

platform_metrics.reset_safe_area_insets()

reset()

yield

reset()

def test_native_viewport_payload_publishes_density_and_screen(_metrics: None) -> None:

"""The host payload's scale, font_scale, screen_width, and screen_height land in platform_metrics."""

from pythonnative import platform_metrics

from pythonnative.hosts.native import _publish_metrics

assert _publish_metrics(

{

"width": 390,

"height": 700,

"scale": 3,

"font_scale": 1.25,

"screen_width": 390,

"screen_height": 844,

"keyboard_height": 144,

}

) == (390.0, 700.0)

window = platform_metrics.get_window_dimensions()

assert (window.width, window.height, window.scale, window.font_scale) == (390.0, 700.0, 3.0, 1.25)

screen = platform_metrics.get_screen_dimensions()

assert (screen.width, screen.height, screen.scale, screen.font_scale) == (390.0, 844.0, 3.0, 1.25)

assert platform_metrics.get_keyboard_height() == 144.0

def test_native_viewport_payload_falls_back_without_density_or_screen(_metrics: None) -> None:

"""A payload with only width and height keeps scale 1.0 and reports the window as the screen."""

from pythonnative import platform_metrics

from pythonnative.hosts.native import _publish_metrics

_publish_metrics({"width": 360, "height": 800, "scale": "3", "font_scale": None})

window = platform_metrics.get_window_dimensions()

assert window == platform_metrics.WindowDimensions(360.0, 800.0, 1.0, 1.0)

assert platform_metrics.get_screen_dimensions() == window

# A later payload without density keeps the density an earlier one reported.

_publish_metrics({"width": 360, "height": 800, "scale": 2.625, "font_scale": 1.1})

_publish_metrics({"width": 800, "height": 360})

window = platform_metrics.get_window_dimensions()

assert (window.width, window.scale, window.font_scale) == (800.0, 2.625, 1.1)

assert _publish_metrics("not a dict") == (0.0, 0.0)

# ======================================================================

# RedBox

# ======================================================================

def test_mount_error_shows_redbox_in_dev_mode(monkeypatch: pytest.MonkeyPatch, backend: FakeBackend) -> None:

monkeypatch.setattr(diagnostics, "_dev_mode", True)

@component

def Root() -> Element:

raise RuntimeError("kaboom")

host = create_screen(_install_app_module(monkeypatch, "redbox_app", Root))

host.on_create()

from pythonnative.bridge import get_transport

assert host._redbox_visible

payload = cast(FakeTransport, get_transport()).calls[-1][2]

assert "RuntimeError in mount: kaboom" == payload["title"]

assert "kaboom" in payload["trace"]

assert backend.live_view_count() == 0

host.clear_redbox()

assert not host._redbox_visible

host.on_destroy()

def test_render_error_shows_redbox_and_dismiss_restores_tree(

monkeypatch: pytest.MonkeyPatch, backend: FakeBackend

) -> None:

monkeypatch.setattr(diagnostics, "_dev_mode", True)

setter: dict = {}

@component

def Root() -> Element:

broken, set_broken = use_state(False)

setter["set"] = set_broken

if broken:

raise RuntimeError("render broke")

return Element("Text", {"text": "fine"}, [])

host = create_screen(_install_app_module(monkeypatch, "redbox_render_app", Root))

host.on_create()

assert not host._redbox_visible

assert _text_of(host.root_native_view) == ["fine"]

setter["set"](True)

settle()

from pythonnative.bridge import get_transport

assert host._redbox_visible

assert "RuntimeError in render" in cast(FakeTransport, get_transport()).calls[-1][2]["title"]

assert _text_of(host.root_native_view) == ["fine"]

assert backend.live_view_count() == 1

host.clear_redbox()

assert not host._redbox_visible

host.on_destroy()

def test_mount_error_propagates_outside_dev_mode(monkeypatch: pytest.MonkeyPatch, backend: FakeBackend) -> None:

monkeypatch.setattr(diagnostics, "_dev_mode", False)

@component

def Root() -> Element:

raise RuntimeError("kaboom")

host = create_screen(_install_app_module(monkeypatch, "redbox_off_app", Root))

with pytest.raises(RuntimeError, match="kaboom"):

host.on_create()

assert not host._redbox_visible

host.on_destroy()

# ======================================================================

# Component resolution

# ======================================================================

def test_import_component_propagates_real_dependency_errors(

tmp_path: Path,

monkeypatch: pytest.MonkeyPatch,

) -> None:

"""A failing import *inside* the app must not be masked.

Regression: ``import_component`` caught every ``ModuleNotFoundError``

and reported a generic "could not resolve component", hiding the real

cause (e.g. a dependency the developer forgot to install). The actual

error must propagate, while a genuinely absent path still yields the

friendly resolve error. This is what makes ``pn preview`` surface

``No module named 'emoji'`` instead of a misleading message.

"""

pkg = tmp_path / "resolver_app"

pkg.mkdir()

(pkg / "__init__.py").write_text("", encoding="utf-8")

(pkg / "good.py").write_text("def App():\n return None\n\ndef Other():\n return None\n", encoding="utf-8")

(pkg / "bad.py").write_text(

"import a_dependency_that_is_not_installed_xyz\n\ndef App():\n return None\n",

encoding="utf-8",

)

monkeypatch.syspath_prepend(os.fspath(tmp_path))

monkeypatch.setattr(sys, "dont_write_bytecode", True)

for name in ("resolver_app", "resolver_app.good", "resolver_app.bad"):

sys.modules.pop(name, None)

# A resolvable module returns its ``App``; a dotted path returns the named attribute.

assert import_component("resolver_app.good").__name__ == "App"

assert import_component("resolver_app.good.Other").__name__ == "Other"

# The module exists but imports a missing dependency: the real

# ``ModuleNotFoundError`` (naming that dependency) must propagate.

with pytest.raises(ModuleNotFoundError) as excinfo:

import_component("resolver_app.bad")

assert excinfo.value.name == "a_dependency_that_is_not_installed_xyz"

# A genuinely absent path still gives the friendly resolve error.

with pytest.raises(ImportError, match="Could not resolve component"):

import_component("resolver_app.nope_does_not_exist")

pythonnative/tests/test_hosts.py at main · pythonnative/pythonnative · GitHub

Repository navigation

Expand file tree

Breadcrumbs

test_hosts.py

Latest commit

History

Breadcrumbs

test_hosts.py

File metadata and controls