mypy: Fix typing around browsertab/webkittab/webenginetab

See #5368
See #4800

qutebrowser/browser/browsertab.py

@@ -23,6 +23,7 @@
 import itertools
 import typing
 import functools
+import typing
 
 import attr
 from PyQt5.QtCore import (pyqtSignal, pyqtSlot, QUrl, QObject, QSizeF, Qt,
@@ -71,7 +72,7 @@ def create(win_id: int,
     mode_manager = modeman.instance(win_id)
     if objects.backend == usertypes.Backend.QtWebEngine:
         from qutebrowser.browser.webengine import webenginetab
-        tab_class = webenginetab.WebEngineTab
+        tab_class = webenginetab.WebEngineTab  # type: typing.Type[AbstractTab]
     else:
         from qutebrowser.browser.webkit import webkittab
         tab_class = webkittab.WebKitTab
@@ -438,16 +439,15 @@ class AbstractCaret(QObject):
     follow_selected_done = pyqtSignal()
 
     def __init__(self,
-                 tab: 'AbstractTab',
                  mode_manager: modeman.ModeManager,
                  parent: QWidget = None) -> None:
         super().__init__(parent)
-        self._tab = tab
         self._widget = typing.cast(QWidget, None)
         self.selection_enabled = False
         self._mode_manager = mode_manager
         mode_manager.entered.connect(self._on_mode_entered)
         mode_manager.left.connect(self._on_mode_left)
+        # self._tab is set by subclasses so mypy knows its concrete type.
 
     def _on_mode_entered(self, mode: usertypes.KeyMode) -> None:
         raise NotImplementedError
@@ -689,9 +689,9 @@ class AbstractElements:
         [typing.Optional['webelem.AbstractWebElement']], None]
     _ErrorCallback = typing.Callable[[Exception], None]
 
-    def __init__(self, tab: 'AbstractTab') -> None:
+    def __init__(self) -> None:
         self._widget = typing.cast(QWidget, None)
-        self._tab = tab
+        # self._tab is set by subclasses so mypy knows its concrete type.
 
     def find_css(self, selector: str,
                  callback: _MultiCallback,
@@ -876,8 +876,11 @@ class AbstractTab(QWidget):
     # for a given hostname anyways.
     _insecure_hosts = set()  # type: typing.Set[str]
 
-    def __init__(self, *, win_id: int, private: bool,
+    def __init__(self, *, win_id: int,
+                 mode_manager: modeman.ModeManager,
+                 private: bool,
                  parent: QWidget = None) -> None:
+        utils.unused(mode_manager)  # needed for mypy
         self.is_private = private
         self.win_id = win_id
         self.tab_id = next(tab_id_gen)

qutebrowser/browser/webengine/webenginetab.py

@@ -41,6 +41,7 @@
 from qutebrowser.misc import miscwidgets, objects
 from qutebrowser.utils import (usertypes, qtutils, log, javascript, utils,
                                message, objreg, jinja, debug)
+from qutebrowser.keyinput import modeman
 from qutebrowser.qt import sip
 
 
@@ -336,6 +337,13 @@ class WebEngineCaret(browsertab.AbstractCaret):
 
     """QtWebEngine implementations related to moving the cursor/selection."""
 
+    def __init__(self,
+                 tab: 'WebEngineTab',
+                 mode_manager: modeman.ModeManager,
+                 parent: QWidget = None) -> None:
+        super().__init__(mode_manager, parent)
+        self._tab = tab
+
     def _flags(self):
         """Get flags to pass to JS."""
         flags = set()
@@ -713,6 +721,10 @@ class WebEngineElements(browsertab.AbstractElements):
 
     """QtWebEngine implemementations related to elements on the page."""
 
+    def __init__(self, tab: 'WebEngineTab') -> None:
+        super().__init__()
+        self._tab = tab
+
     def _js_cb_multiple(self, callback, error_cb, js_elems):
         """Handle found elements coming from JS and call the real callback.
 
@@ -1244,7 +1256,10 @@ class WebEngineTab(browsertab.AbstractTab):
     abort_questions = pyqtSignal()
 
     def __init__(self, *, win_id, mode_manager, private, parent=None):
-        super().__init__(win_id=win_id, private=private, parent=parent)
+        super().__init__(win_id=win_id,
+                         mode_manager=mode_manager,
+                         private=private,
+                         parent=parent)
         widget = webview.WebEngineView(tabdata=self.data, win_id=win_id,
                                        private=private)
         self.history = WebEngineHistory(tab=self)

qutebrowser/browser/webkit/webkittab.py

@@ -27,12 +27,14 @@
 from PyQt5.QtGui import QIcon
 from PyQt5.QtWebKitWidgets import QWebPage, QWebFrame
 from PyQt5.QtWebKit import QWebSettings
+from PyQt5.QtWidgets import QWidget
 from PyQt5.QtPrintSupport import QPrinter
 
 from qutebrowser.browser import browsertab, shared
 from qutebrowser.browser.webkit import (webview, tabhistory, webkitelem,
                                         webkitsettings)
 from qutebrowser.utils import qtutils, usertypes, utils, log, debug
+from qutebrowser.keyinput import modeman
 from qutebrowser.qt import sip
 
 
@@ -172,6 +174,13 @@ class WebKitCaret(browsertab.AbstractCaret):
 
     """QtWebKit implementations related to moving the cursor/selection."""
 
+    def __init__(self,
+                 tab: 'WebKitTab',
+                 mode_manager: modeman.ModeManager,
+                 parent: QWidget = None) -> None:
+        super().__init__(mode_manager, parent)
+        self._tab = tab
+
     @pyqtSlot(usertypes.KeyMode)
     def _on_mode_entered(self, mode):
         if mode != usertypes.KeyMode.caret:
@@ -582,6 +591,10 @@ class WebKitElements(browsertab.AbstractElements):
 
     """QtWebKit implemementations related to elements on the page."""
 
+    def __init__(self, tab: 'WebKitTab') -> None:
+        super().__init__()
+        self._tab = tab
+
     def find_css(self, selector, callback, error_cb, *, only_visible=False):
         utils.unused(error_cb)
         mainframe = self._widget.page().mainFrame()
@@ -699,7 +712,10 @@ class WebKitTab(browsertab.AbstractTab):
     """A QtWebKit tab in the browser."""
 
     def __init__(self, *, win_id, mode_manager, private, parent=None):
-        super().__init__(win_id=win_id, private=private, parent=parent)
+        super().__init__(win_id=win_id,
+                         mode_manager=mode_manager,
+                         private=private,
+                         parent=parent)
         widget = webview.WebView(win_id=win_id, tab_id=self.tab_id,
                                  private=private, tab=self)
         if private: