Make testbrowser.py run without QtWebKit

scripts/testbrowser.py

@@ -25,14 +25,16 @@ import argparse
 
 from PyQt5.QtCore import QUrl
 from PyQt5.QtWidgets import QApplication
-from PyQt5.QtWebKit import QWebSettings
-from PyQt5.QtWebKitWidgets import QWebView
+
+try:
+    from PyQt5.QtWebKitWidgets import QWebView
+except ImportError:
+    QWebView = None
 
 try:
     from PyQt5.QtWebEngineWidgets import QWebEngineView
-    WEBENGINE = True
 except ImportError:
-    WEBENGINE = False
+    QWebEngineView = None
 
 
 def parse_args():
@@ -41,7 +43,7 @@ def parse_args():
     parser.add_argument('url', help='The URL to open')
     parser.add_argument('--plugins', '-p', help='Enable plugins',
                         default=False, action='store_true')
-    if WEBENGINE:
+    if QWebEngineView is not None:
         parser.add_argument('--webengine', help='Use QtWebEngine',
                             default=False, action='store_true')
     return parser.parse_args()
@@ -51,16 +53,29 @@ if __name__ == '__main__':
     args = parse_args()
     app = QApplication(sys.argv)
 
-    if WEBENGINE and args.webengine:
+    if QWebView is None and QWebEngineView is None:
+        print("Found no suitable backend to run with!")
+        sys.exit(1)
+    elif QWebView is None and not args.webengine:
+        print("Using QtWebEngine because QtWebKit is unavailable")
         wv = QWebEngineView()
+        using_webengine = True
+    elif args.webengine:
+        if QWebEngineView is None:
+            print("Requested QtWebEngine, but it could not be imported!")
+            sys.exit(1)
+        wv = QWebEngineView()
+        using_webengine = True
     else:
         wv = QWebView()
+        using_webengine = False
 
     wv.loadStarted.connect(lambda: print("Loading started"))
     wv.loadProgress.connect(lambda p: print("Loading progress: {}%".format(p)))
     wv.loadFinished.connect(lambda: print("Loading finished"))
 
-    if args.plugins and not WEBENGINE:
+    if args.plugins and not using_webengine:
+        from PyQt5.QtWebKit import QWebSettings
         wv.settings().setAttribute(QWebSettings.PluginsEnabled, True)
 
     wv.load(QUrl.fromUserInput(args.url))