First stab at running e2e tests in GitHub Actions.

Uses the method from debian package autopkgtest.

.github/workflows/python-app.yml

@@ -37,3 +37,21 @@ jobs:
     - name: Smoke test import
       run: |
         python -c 'import bambam'
+
+    - name: Install GUI packages
+      run: |
+        sudo apt-get install -y xvfb xauth imagemagick xdotool
+
+    - name: Run GUI tests
+      run: |
+        export AUTOPKGTEST_ARTIFACTS=`pwd`/artifacts
+        mkdir -p $AUTOPKGTEST_ARTIFACTS
+        export AUTOPKGTEST_TMP=/tmp
+        export AUTOPKGTEST_BAMBAM_PROGRAM=./bambam.py
+        xvfb-run -e $AUTOPKGTEST_ARTIFACTS/xvfb-run.stderr -s "-screen 0 1024x768x24 -fbdir $AUTOPKGTEST_TMP" ./test-e2e.py
+
+    - name: Save artifacts
+      uses: actions/upload-artifact@v3
+      with:
+        name: test-artifacts-${{ matrix.python-version }}
+        path: artifacts

test-e2e.py

@@ -0,0 +1,174 @@
+#!/usr/bin/env python3
+# Copyright (C) 2018-2023 Marcin Owsiany <[email protected]>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""Checks whether bambam works.
+
+This is intended to be run by autopkgtest, with the environment set up to
+connect to an Xvfb server in order to take screenshots from its XWD output
+file.
+
+See the main() function for a high-level overview of what the script does.
+"""
+
+import logging
+import os
+import random
+import re
+import subprocess
+import time
+
+
+_COLOR_PATTERN = re.compile(r'(\d+),(\d+),(\d+)')
+_EXIT_SECONDS = 5
+_BAMBAM_PROGRAM = os.getenv('AUTOPKGTEST_BAMBAM_PROGRAM', '/usr/games/bambam')
+
+
+def main():
+    bambam = subprocess.Popen([_BAMBAM_PROGRAM])
+    try:
+        await_welcome_screen()
+        send_keycodes('space')  # any keypress should do
+        await_blank_screen()
+        test_functionality()
+        shut_bambam_down()
+        logging.info('Waiting for game to exit cleanly.')
+        exit_code = bambam.wait(timeout=_EXIT_SECONDS)
+        if exit_code != 0:
+            raise Exception('Bambam exited with unexpected code %d.' % exit_code)
+        logging.info('Test successful.')
+    except:  # noqa: E722
+        take_screenshot('exception')
+        raise
+
+
+def await_welcome_screen():
+    logging.info(
+        'Polling to observe a light blue screen (which means that bambam '
+        'has started AND is displaying a welcome screen where the text '
+        'is blue).')
+    attempt_count = 40
+    sleep_delay = 0.25
+    for attempt in range(attempt_count):
+        current_average_hsl = get_average_hsl()
+        logging.info('On attempt %d the average screen HSV was %s.', attempt, current_average_hsl)
+        h, s, l = current_average_hsl  # noqa: E741
+        if 50 < h and h < 70 and 20 < s and s < 40 and 80 < l and l < 100:
+            logging.info('Found light blue screen, looks like bambam started up OK.')
+            take_screenshot('welcome')
+            return
+        time.sleep(sleep_delay)
+    raise Exception(
+        'Failed to see bambam start and display light-blue background, '
+        'after polling %d times every %f seconds.' % (attempt_count, sleep_delay))
+
+
+def await_blank_screen():
+    logging.info('Polling to observe a mostly-white screen (which means that welcome screen was cleared).')
+    attempt_count = 40
+    sleep_delay = 0.25
+    for attempt in range(attempt_count):
+        current_average_color = get_average_color()
+        logging.info('On attempt %d the average screen color was %s.', attempt, current_average_color)
+        if all(color_component >= 248 for color_component in current_average_color):
+            logging.info('Found mostly white screen, looks like bambam cleared the welcome screen OK.')
+            take_screenshot('blank')
+            return
+        time.sleep(sleep_delay)
+    raise Exception(
+        'Failed to see bambam clear the startup screen and display mostly-white background, '
+        'after polling %d times every %f seconds.' % (attempt_count, sleep_delay))
+
+
+def test_functionality():
+    logging.info('Simulating space and letter keypresses and measuring average screen color, to test functionality.')
+    attempt_count = 1000
+    for attempt in range(attempt_count):
+        send_keycodes('space', 'm')  # any letter will do, but em is nice and big
+        send_mouse_move()
+        time.sleep(0.005)  # let the event propagate and bambam process it
+        if is_screen_colorful_enough(attempt):
+            take_screenshot('success')
+            return
+    raise Exception('Failed to see a colorful enough screen after %d key presses.' % (attempt_count * 2))
+
+
+def is_screen_colorful_enough(attempt):
+    r, g, b = get_average_color()
+    if any(color > 225 for color in (r, g, b)):
+        logging.info('On attempt %d the average screen color was too close to white: %d,%d,%d.', attempt, r, g, b)
+        return False
+    else:
+        logging.info('Found colorful enough screen, colors %d, %d, %d.', r, g, b)
+        return True
+
+
+def shut_bambam_down():
+    logging.info('Simulating shutdown keypresses.')
+    send_keycodes('q', 'u', 'i', 't')
+
+
+def take_screenshot(title):
+    file_name = os.path.join(os.environ['AUTOPKGTEST_ARTIFACTS'], '%s.png' % title)
+    subprocess.call([
+        'convert',
+        'xwd:' + os.path.join(os.environ['AUTOPKGTEST_TMP'], 'Xvfb_screen0'),
+        file_name])
+    logging.info('Took a screenshot to: %s', file_name)
+
+
+def get_average_color():
+    return summarize_screen('r*255', 'g*255', 'b*255')
+
+
+def get_average_hsl():
+    return summarize_screen('hue*100', 'saturation*100', 'lightness*100')
+
+
+def summarize_screen(*fx_expressions):
+    if len(fx_expressions) != 3:
+        raise Exception('Expected three FX expressions, got %s' % fx_expressions)
+    format_arg = ','.join(('%%[fx:int(%s)]' % e) for e in fx_expressions)
+    color_str = subprocess.check_output([
+        'convert',
+        'xwd:' + os.path.join(os.environ['AUTOPKGTEST_TMP'], 'Xvfb_screen0'),
+        '-resize', '1x1!',
+        '-format', format_arg,
+        'info:-']).decode()
+    m = _COLOR_PATTERN.match(color_str)
+    if not m:
+        raise Exception('Failed to parse color ' + color_str)
+    return [int(i) for i in m.group(1, 2, 3)]
+
+
+def xdotool(*args):
+    subprocess.check_call(['xdotool', 'search', '--class', 'bambam'] + list(args))
+
+
+def send_keycodes(*keycodes):
+    xdotool('key', *keycodes)
+
+
+def random_move():
+    return random.choice(['+', '-']) + str(random.choice(range(1, 50)))
+
+
+def send_mouse_move():
+    x, y = random_move(), random_move()
+    xdotool('mousedown', '1', 'mousemove_relative', '--', x, y, 'mouseup', '1')
+
+
+if __name__ == '__main__':
+    logging.basicConfig(level=logging.INFO, format="%(asctime)s %(levelname)s %(name)s: %(message)s")
+    main()