#!/usr/bin/env python3 import os import sys import unittest from unittest.mock import patch from xvfbwrapper import Xvfb # Force X11 in case we are running on a Wayland system os.environ["XDG_SESSION_TYPE"] = "x11" # Using mock.patch as a class decorator applies it to every # test_* method and removes it after test completes. @patch.dict("os.environ", {"DISPLAY": ":0"}) class TestXvfb(unittest.TestCase): def setUp(self): pass def tearDown(self): pass def test_xvfb_binary_does_not_exist(self): with patch("xvfbwrapper.Xvfb._xvfb_exists") as xvfb_exists: xvfb_exists.return_value = False with self.assertRaises(EnvironmentError): Xvfb() def test_start(self): xvfb = Xvfb() self.addCleanup(xvfb.stop) xvfb.start() display_var = f":{xvfb.new_display}" self.assertEqual(display_var, os.environ["DISPLAY"]) self.assertIsNotNone(xvfb.proc) def test_stop(self): orig_display = os.environ["DISPLAY"] xvfb = Xvfb() xvfb.start() self.assertNotEqual(orig_display, os.environ["DISPLAY"]) xvfb.stop() self.assertEqual(orig_display, os.environ["DISPLAY"]) self.assertIsNone(xvfb.proc) def test_stop_with_xquartz(self): # Check that xquartz pattern for display server is dealt with by # xvfb.stop() and restored appropriately xquartz_display = ( "/private/tmp/com.apple.launchd.CgDzCWvNb1/org.macosforge.xquartz:0" ) with patch.dict("os.environ", {"DISPLAY": xquartz_display}): xvfb = Xvfb() xvfb.start() self.assertNotEqual(xquartz_display, os.environ["DISPLAY"]) xvfb.stop() self.assertEqual(xquartz_display, os.environ["DISPLAY"]) self.assertIsNone(xvfb.proc) def test_start_and_stop_as_context_manager(self): orig_display = os.environ["DISPLAY"] with Xvfb() as xvfb: display_var = f":{xvfb.new_display}" self.assertEqual(display_var, os.environ["DISPLAY"]) self.assertIsNotNone(xvfb.proc) self.assertEqual(orig_display, os.environ["DISPLAY"]) self.assertIsNone(xvfb.proc) def test_start_without_existing_display(self): with patch.dict("os.environ", {}): del os.environ["DISPLAY"] xvfb = Xvfb() self.addCleanup(xvfb.stop) xvfb.start() display_var = f":{xvfb.new_display}" self.assertEqual(display_var, os.environ["DISPLAY"]) self.assertIsNotNone(xvfb.proc) def test_start_with_empty_display(self): with patch.dict("os.environ", {}): os.environ["DISPLAY"] = "" xvfb = Xvfb() self.addCleanup(xvfb.stop) xvfb.start() display_var = f":{xvfb.new_display}" self.assertEqual(display_var, os.environ["DISPLAY"]) self.assertIsNotNone(xvfb.proc) def test_start_with_specific_display(self): xvfb = Xvfb(display=42) xvfb2 = Xvfb(display=42) self.addCleanup(xvfb.stop) xvfb.start() self.assertEqual(xvfb.new_display, 42) self.assertIsNotNone(xvfb.proc) with self.assertRaises(ValueError): xvfb2.start() def test_start_with_kwargs(self): w = 800 h = 600 depth = 16 xvfb = Xvfb(width=w, height=h, colordepth=depth) self.addCleanup(xvfb.stop) xvfb.start() self.assertEqual(w, xvfb.width) self.assertEqual(h, xvfb.height) self.assertEqual(depth, xvfb.colordepth) display_var = f":{xvfb.new_display}" self.assertEqual(display_var, os.environ["DISPLAY"]) self.assertIsNotNone(xvfb.proc) def test_start_with_arbitrary_kwargs(self): xvfb = Xvfb(nolisten="tcp") self.addCleanup(xvfb.stop) xvfb.start() display_var = f":{xvfb.new_display}" self.assertEqual(display_var, os.environ["DISPLAY"]) self.assertIsNotNone(xvfb.proc) def test_start_fails_with_unknown_kwargs(self): xvfb = Xvfb(foo="bar") with self.assertRaises(RuntimeError): xvfb.start() def test_get_next_unused_display_does_not_reuse_lock(self): xvfb = Xvfb() xvfb2 = Xvfb() xvfb3 = Xvfb() self.addCleanup(xvfb._cleanup_lock_file) self.addCleanup(xvfb2._cleanup_lock_file) self.addCleanup(xvfb3._cleanup_lock_file) side_effect = [11, 11, 22, 11, 22, 11, 22, 22, 22, 33] with patch("xvfbwrapper.randint", side_effect=side_effect) as mockrandint: self.assertEqual(xvfb._get_next_unused_display(), 11) self.assertEqual(mockrandint.call_count, 1) if sys.implementation.name == "cpython": # ResourceWarning is only raised on CPython because # of an implementation detail in it's garbage collector. # This does not occur on other Python implementations # (like PyPy). with self.assertWarns(ResourceWarning): self.assertEqual(xvfb2._get_next_unused_display(), 22) self.assertEqual(mockrandint.call_count, 3) self.assertEqual(xvfb3._get_next_unused_display(), 33) self.assertEqual(mockrandint.call_count, 10) else: self.assertEqual(xvfb2._get_next_unused_display(), 22) self.assertEqual(mockrandint.call_count, 3) self.assertEqual(xvfb3._get_next_unused_display(), 33) self.assertEqual(mockrandint.call_count, 10) def test_environ_keyword_isolates_environment_modification(self): # Check that start and stop methods modified the environ dict if # passed and does not modify os.environ env_duped = os.environ.copy() xvfb = Xvfb(environ=env_duped) xvfb.start() new_display = f":{xvfb.new_display}" self.assertEqual(":0", os.environ["DISPLAY"]) self.assertEqual(new_display, env_duped["DISPLAY"]) xvfb.stop() self.assertEqual(":0", os.environ["DISPLAY"]) self.assertEqual(":0", env_duped["DISPLAY"]) self.assertIsNone(xvfb.proc) def test_start_failure_without_initial_display_env(self): # Provide a custom env *without* DISPLAY so orig_display_var == None custom_env = {"PATH": os.environ.get("PATH", "")} xvfb = Xvfb(timeout=0.5, environ=custom_env) # Ensure any spawned proc is cleaned up self.addCleanup(lambda: xvfb.proc and xvfb.proc.terminate()) # Force the display socket to never appear with patch.object(xvfb, "_local_display_exists", return_value=False): # On old code this will KeyError *inside* stop() # On fixed code this raises RuntimeError cleanly with self.assertRaises(RuntimeError): xvfb.start() # After failure, calling stop() again must not raise an exception xvfb.stop() # We never injected DISPLAY into our custom env self.assertNotIn("DISPLAY", custom_env) # There should be no lingering proc self.assertIsNone(xvfb.proc)