Test app

android/MANIFEST.in

@@ -3,3 +3,4 @@ include LICENSE
 include README.rst
 include tox.ini
 recursive-include tests *.py
+recursive-include test_probes *.py

android/test_probes/utils.py

@@ -0,0 +1,15 @@
+from java import jint
+
+from android.graphics import Color
+from toga.colors import rgba
+
+
+def toga_color(color_int):
+    # Select the `int` overloads rather than the `long` ones.
+    color_int = jint(color_int)
+    return rgba(
+        Color.red(color_int),
+        Color.green(color_int),
+        Color.blue(color_int),
+        Color.alpha(color_int) / 255,
+    )

android/test_probes/widgets/probe_base.py

@@ -0,0 +1,40 @@
+from pytest import skip
+
+
+class SimpleProbe:
+    def __init__(self, main_box, widget):
+        native_box = main_box._impl.native
+        assert native_box.getChildCount() == 1
+        self.native = native_box.getChildAt(0)
+        assert isinstance(self.native, self.native_class)
+
+        # Although this isn't part of the public API, we often point users at it to do
+        # things that Toga itself doesn't support.
+        assert widget._impl.native is self.native
+
+    @property
+    def enabled(self):
+        return self.native.isEnabled()
+
+    @property
+    def background_color(self):
+        skip("not implemented: background_color")
+
+    @property
+    def color(self):
+        skip("not implemented: color")
+
+    @property
+    def hidden(self):
+        skip("not implemented: hidden")
+
+    @property
+    def width(self):
+        return self.native.getWidth()
+
+    @property
+    def height(self):
+        return self.native.getHeight()
+
+    def press(self):
+        self.native.performClick()

android/test_probes/widgets/probe_button.py

@@ -0,0 +1,8 @@
+from java import jclass
+
+from .probe_label import LabelProbe
+
+
+# On Android, a Button is just a TextView with a state-dependent background image.
+class ButtonProbe(LabelProbe):
+    native_class = jclass("android.widget.Button")

android/test_probes/widgets/probe_label.py

@@ -0,0 +1,16 @@
+from java import jclass
+
+from ..utils import toga_color
+from .probe_base import SimpleProbe
+
+
+class LabelProbe(SimpleProbe):
+    native_class = jclass("android.widget.TextView")
+
+    @property
+    def color(self):
+        return toga_color(self.native.getCurrentTextColor())
+
+    @property
+    def text(self):
+        return str(self.native.getText())

android/test_probes/widgets/probe_slider.py

@@ -0,0 +1,24 @@
+from java import jclass
+
+from android.os import Build
+
+from .probe_base import SimpleProbe
+
+
+class SliderProbe(SimpleProbe):
+    native_class = jclass("android.widget.SeekBar")
+
+    @property
+    def position(self):
+        return (self.native.getProgress() - self._min) / (self._max - self._min)
+
+    def change(self, position):
+        self.native.setProgress(self._min + round(position * (self._max - self._min)))
+
+    @property
+    def _min(self):
+        return 0 if (Build.VERSION.SDK_INT < 26) else self.native.getMin()
+
+    @property
+    def _max(self):
+        return self.native.getMax()

changes/1687.misc.rst

@@ -0,0 +1 @@
+Added a backend test app.

pyproject.toml

@@ -35,6 +35,7 @@ known_first_party = [
     "toga_dummy",
     "toga_gtk",
     "toga_iOS",
+    "toga_test",
     "toga_web",
     "toga_winforms",
 ]

test/.gitignore

@@ -0,0 +1,69 @@
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# OSX useful to ignore
+*.DS_Store
+.AppleDouble
+.LSOverride
+
+# Thumbnails
+._*
+
+# Files that might appear in the root of a volume
+.DocumentRevisions-V100
+.fseventsd
+.Spotlight-V100
+.TemporaryItems
+.Trashes
+.VolumeIcon.icns
+.com.apple.timemachine.donotpresent
+
+# Directories potentially created on remote AFP share
+.AppleDB
+.AppleDesktop
+Network Trash Folder
+Temporary Items
+.apdisk
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+env/
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+*.egg-info/
+.installed.cfg
+*.egg
+
+# IntelliJ Idea family of suites
+.idea
+*.iml
+## File-based project format:
+*.ipr
+*.iws
+## mpeltonen/sbt-idea plugin
+.idea_modules/
+
+# Briefcase build directories
+iOS/
+macOS/
+windows/
+android/
+linux/
+django/
+
+# Briefcase log files
+logs/

test/pyproject.toml

@@ -0,0 +1,91 @@
+# This project was generated using template: https://github.com/beeware/briefcase-template and branch: v0.3.12
+[tool.briefcase]
+project_name = "Toga test"
+bundle = "org.beeware"
+version = "0.0.1"
+url = "https://beeware.org"
+license = "BSD license"
+author = 'Tiberius Yak'
+author_email = "[email protected]"
+
+[tool.briefcase.app.toga-test]
+formal_name = "Toga test"
+description = "Toga test"
+icon = "src/toga_test/resources/toga_test"
+sources = [
+    'src/toga_test',
+]
+test_sources = [
+    'tests',
+]
+requires = [
+    '../core',
+    '../dummy',
+]
+test_requires = [
+    'pytest==7.2.0',
+    'pytest-asyncio==0.20.2',
+]
+
+
+[tool.briefcase.app.toga-test.macOS]
+requires = [
+    '../cocoa',
+    'std-nslog~=1.0.0'
+]
+
+[tool.briefcase.app.toga-test.linux]
+requires = [
+    '../gtk',
+]
+
+[tool.briefcase.app.toga-test.linux.appimage]
+system_requires = [
+    'gir1.2-webkit-3.0',
+    'libcairo2-dev',
+    'libgirepository1.0-dev',
+    'libgtk-3-dev',
+    'libpango1.0-dev',
+    'librsvg2-dev',
+    'libwebkitgtk-3.0-0',
+]
+linuxdeploy_plugins = [
+    'DEPLOY_GTK_VERSION=3 gtk',
+]
+
+[tool.briefcase.app.toga-test.linux.flatpak]
+flatpak_runtime = 'org.gnome.Platform'
+flatpak_runtime_version = '42'
+flatpak_sdk = 'org.gnome.Sdk'
+
+[tool.briefcase.app.toga-test.windows]
+test_sources = [
+    '../winforms/test_probes',
+]
+requires = [
+    '../winforms',
+]
+
+# Mobile deployments
+[tool.briefcase.app.toga-test.iOS]
+requires = [
+    '../iOS',
+    'std-nslog~=1.0.0'
+]
+
+[tool.briefcase.app.toga-test.android]
+test_sources = [
+    '../android/test_probes',
+]
+requires = [
+    '../android'
+]
+
+# TODO: replace with extractPackages
+build_gradle_extra_content = "android.defaultConfig.python.pyc.src false"
+
+[tool.briefcase.app.toga-test.web]
+requires = [
+    '../web'
+]
+style_framework = "Bootstrap v4.6"

test/src/toga_test/__main__.py

@@ -0,0 +1,4 @@
+from toga_test.app import main
+
+if __name__ == "__main__":
+    main().main_loop()

test/src/toga_test/app.py

@@ -0,0 +1,18 @@
+import toga
+
+
+class TogaTest(toga.App):
+    def startup(self):
+        # For the "app" fixture.
+        global app
+        app = self
+
+        self.main_box = toga.Box()
+
+        self.main_window = toga.MainWindow(title=self.formal_name)
+        self.main_window.content = self.main_box
+        self.main_window.show()
+
+
+def main():
+    return TogaTest(app_name="toga_test")

test/tests/conftest.py

@@ -0,0 +1,57 @@
+import asyncio
+import inspect
+from dataclasses import dataclass
+
+from pytest import fixture
+
+import toga_test.app
+
+
+@fixture(scope="session")
+def app():
+    return toga_test.app.app
+
+
+@fixture(scope="session")
+def main_box(app):
+    return app.main_box
+
+
+# Controls the event loop used by pytest-asyncio.
+@fixture(scope="session")
+def event_loop(app):
+    return ProxyEventLoop(app._impl.loop)
+
+
+# Proxy which forwards all tasks to another event loop in a thread-safe manner. It
+# implements only the methods used by pytest-asyncio.
+@dataclass
+class ProxyEventLoop(asyncio.AbstractEventLoop):
+    loop: object
+
+    # Used by ensure_future.
+    def create_task(self, coro):
+        return ProxyTask(coro)
+
+    def run_until_complete(self, future):
+        if inspect.iscoroutine(future):
+            coro = future
+        elif isinstance(future, ProxyTask):
+            coro = future.coro
+        else:
+            raise TypeError(f"Future type {type(future)} is not currently supported")
+        return asyncio.run_coroutine_threadsafe(coro, self.loop).result()
+
+    def close(self):
+        pass
+
+
+@dataclass
+class ProxyTask:
+    coro: object
+
+    # Used by ensure_future.
+    _source_traceback = None
+
+    def done(self):
+        return False