Add printing to tab API

This fixes printing for QtWebKit, and hopefully will make printing to
PDF work with QtWebEngine with Qt >= 5.7

qutebrowser/browser/browsertab.py

@@ -24,6 +24,7 @@ import itertools
 from PyQt5.QtCore import pyqtSignal, pyqtSlot, QUrl, QObject, QPoint
 from PyQt5.QtGui import QIcon
 from PyQt5.QtWidgets import QWidget, QLayout
+from PyQt5.QtPrintSupport import QPrinter
 
 from qutebrowser.keyinput import modeman
 from qutebrowser.config import config
@@ -105,6 +106,27 @@ class TabData:
         self.inspector = None
 
 
+class AbstractPrinting:
+
+    """Attribute of AbstractTab for printing the page."""
+
+    def __init__(self):
+        self._widget = None
+
+    def check_pdf_support(self):
+        raise NotImplementedError
+
+    def check_printer_support(self):
+        raise NotImplementedError
+
+    def to_pdf(self, filename):
+        raise NotImplementedError
+
+    @pyqtSlot(QPrinter)
+    def to_printer(self, printer):
+        raise NotImplementedError
+
+
 class AbstractSearch(QObject):
 
     """Attribute of AbstractTab for doing searches.
@@ -468,6 +490,7 @@ class AbstractTab(QWidget):
         #                            parent=self)
         # self.zoom = AbstractZoom(win_id=win_id)
         # self.search = AbstractSearch(parent=self)
+        # self.printing = AbstractPrinting()
         self.data = TabData()
         self._layout = None
         self._widget = None
@@ -485,6 +508,7 @@ class AbstractTab(QWidget):
         self.caret._widget = widget
         self.zoom._widget = widget
         self.search._widget = widget
+        self.printing._widget = widget
         widget.mouse_wheel_zoom.connect(self.zoom._on_mouse_wheel_zoom)
         widget.setParent(self)
         self.setFocusProxy(widget)

qutebrowser/browser/commands.py

@@ -28,7 +28,7 @@ import functools
 from PyQt5.QtWidgets import QApplication, QTabBar
 from PyQt5.QtCore import Qt, QUrl, QEvent
 from PyQt5.QtGui import QKeyEvent
-from PyQt5.QtPrintSupport import QPrintDialog, QPrinter, QPrintPreviewDialog
+from PyQt5.QtPrintSupport import QPrintDialog, QPrintPreviewDialog
 from PyQt5.QtWebKitWidgets import QWebPage
 try:
     from PyQt5.QtWebEngineWidgets import QWebEnginePage
@@ -308,33 +308,37 @@ class CommandDispatcher:
             count: The tab index to print, or None.
             pdf: The file path to write the PDF to.
         """
-        if not qtutils.check_print_compat():
-            # WORKAROUND (remove this when we bump the requirements to 5.3.0)
-            raise cmdexc.CommandError(
-                "Printing on Qt < 5.3.0 on Windows is broken, please upgrade!")
         tab = self._cntwidget(count)
-        if tab is not None:
+        if tab is None:
-            if preview:
+            return
-                diag = QPrintPreviewDialog()
+
-                diag.setAttribute(Qt.WA_DeleteOnClose)
+        try:
-                diag.setWindowFlags(diag.windowFlags() |
+            if pdf:
-                                    Qt.WindowMaximizeButtonHint |
+                tab.printing.check_pdf_support()
-                                    Qt.WindowMinimizeButtonHint)
-                diag.paintRequested.connect(tab.print)
-                diag.exec_()
-            elif pdf:
-                pdf = os.path.expanduser(pdf)
-                directory = os.path.dirname(pdf)
-                if directory and not os.path.exists(directory):
-                    os.mkdir(directory)
-                printer = QPrinter()
-                printer.setOutputFileName(pdf)
-                tab.print(printer)
-                log.misc.debug("Print to file: {}".format(pdf))
             else:
-                diag = QPrintDialog()
+                tab.printing.check_printer_support()
-                diag.setAttribute(Qt.WA_DeleteOnClose)
+        except browsertab.WebTabError as e:
-                diag.open(lambda: tab.print(diag.printer()))
+            raise cmdexc.CommandError(e)
+
+        if preview:
+            diag = QPrintPreviewDialog()
+            diag.setAttribute(Qt.WA_DeleteOnClose)
+            diag.setWindowFlags(diag.windowFlags() |
+                                Qt.WindowMaximizeButtonHint |
+                                Qt.WindowMinimizeButtonHint)
+            diag.paintRequested.connect(tab.printing.to_printer)
+            diag.exec_()
+        elif pdf:
+            pdf = os.path.expanduser(pdf)
+            directory = os.path.dirname(pdf)
+            if directory and not os.path.exists(directory):
+                os.mkdir(directory)
+            tab.printing.to_pdf(pdf)
+            log.misc.debug("Print to file: {}".format(pdf))
+        else:
+            diag = QPrintDialog()
+            diag.setAttribute(Qt.WA_DeleteOnClose)
+            diag.open(lambda: tab.printing.to_printer(diag.printer()))
 
     @cmdutils.register(instance='command-dispatcher', scope='window')
     def tab_clone(self, bg=False, window=False):

qutebrowser/browser/webengine/webenginetab.py

@@ -25,6 +25,7 @@
 from PyQt5.QtCore import pyqtSlot, Qt, QEvent, QPoint
 from PyQt5.QtGui import QKeyEvent, QIcon
 from PyQt5.QtWidgets import QApplication
+from PyQt5.QtPrintSupport import QPrinter
 # pylint: disable=no-name-in-module,import-error,useless-suppression
 from PyQt5.QtWebEngineWidgets import QWebEnginePage
 # pylint: enable=no-name-in-module,import-error,useless-suppression
@@ -34,6 +35,28 @@ from qutebrowser.browser.webengine import webview
 from qutebrowser.utils import usertypes, qtutils, log
 
 
+class WebEnginePrinting(browsertab.AbstractPrinting):
+
+    """QtWebEngine implementations related to printing."""
+
+    def check_pdf_support(self):
+        if not hasattr(self._widget.page(), 'printToPdf'):
+            raise browsertab.WebTabError(
+                "Printing to PDF is unsupported with QtWebEngine on Qt > 5.7")
+
+    def check_printer_support(self):
+        raise browsertab.WebTabError(
+            "Printing is unsupported with QtWebEngine")
+
+    def to_pdf(self, filename):
+        self._widget.page().printToPdf(filename)
+
+    @pyqtSlot(QPrinter)
+    def to_printer(self, printer):
+        # Should never be called
+        assert False
+
+
 class WebEngineSearch(browsertab.AbstractSearch):
 
     """QtWebEngine implementations related to searching on the page."""
@@ -256,6 +279,7 @@ class WebEngineTab(browsertab.AbstractTab):
                                     tab=self, parent=self)
         self.zoom = WebEngineZoom(win_id=win_id, parent=self)
         self.search = WebEngineSearch(parent=self)
+        self.printing = WebEnginePrinting()
         self._set_widget(widget)
         self._connect_signals()
         self.backend = usertypes.Backend.QtWebEngine

qutebrowser/browser/webkit/webkittab.py

@@ -27,12 +27,39 @@ from PyQt5.QtCore import pyqtSlot, Qt, QEvent, QUrl, QPoint, QTimer
 from PyQt5.QtGui import QKeyEvent
 from PyQt5.QtWebKitWidgets import QWebPage
 from PyQt5.QtWebKit import QWebSettings
+from PyQt5.QtPrintSupport import QPrinter
 
 from qutebrowser.browser import browsertab
 from qutebrowser.browser.webkit import webview, tabhistory
 from qutebrowser.utils import qtutils, objreg, usertypes, utils
 
 
+class WebKitPrinting(browsertab.AbstractPrinting):
+
+    """QtWebKit implementations related to printing."""
+
+    def _do_check(self):
+        if not qtutils.check_print_compat():
+            # WORKAROUND (remove this when we bump the requirements to 5.3.0)
+            raise browsertab.WebTabError(
+                "Printing on Qt < 5.3.0 on Windows is broken, please upgrade!")
+
+    def check_pdf_support(self):
+        self._do_check()
+
+    def check_printer_support(self):
+        self._do_check()
+
+    def to_pdf(self, filename):
+        printer = QPrinter()
+        printer.setOutputFileName(filename)
+        self.to_printer(printer)
+
+    @pyqtSlot(QPrinter)
+    def to_printer(self, printer):
+        self._widget.print(printer)
+
+
 class WebKitSearch(browsertab.AbstractSearch):
 
     """QtWebKit implementations related to searching on the page."""
@@ -461,6 +488,7 @@ class WebKitTab(browsertab.AbstractTab):
                                  tab=self, parent=self)
         self.zoom = WebKitZoom(win_id=win_id, parent=self)
         self.search = WebKitSearch(parent=self)
+        self.printing = WebKitPrinting()
         self._set_widget(widget)
         self._connect_signals()
         self.zoom.set_default()

tests/unit/browser/test_tab.py

@@ -77,6 +77,7 @@ def test_tab(qtbot, view, config_stub, tab_registry):
                                            tab=tab_w, parent=tab_w)
     tab_w.zoom = browsertab.AbstractZoom(win_id=tab_w.win_id)
     tab_w.search = browsertab.AbstractSearch(parent=tab_w)
+    tab_w.printing = browsertab.AbstractPrinting()
 
     tab_w._set_widget(w)
     assert tab_w._widget is w