Bundle editor functions

qutebrowser/browser/curcommand.py

@@ -32,6 +32,7 @@ import qutebrowser.utils.message as message
 import qutebrowser.commands.utils as cmdutils
 import qutebrowser.utils.webelem as webelem
 import qutebrowser.config.config as config
+from qutebrowser.utils.misc import ExternalEditor
 
 
 class CurCommandDispatcher(QObject):
@@ -348,63 +349,19 @@ class CurCommandDispatcher(QObject):
         if elem.isNull():
             message.error("No editable element focused!")
             return
-        oshandle, filename = mkstemp(text=True)
         text = elem.evaluateJavaScript('this.value')
-        if text:
-            with open(filename, 'w') as f:
-                f.write(text)
-        proc = QProcess(self)
-        proc.finished.connect(partial(self.on_editor_closed, elem, oshandle,
-                                      filename))
-        proc.error.connect(partial(self.on_editor_error, oshandle, filename))
-        editor = config.get('general', 'editor')
-        executable = editor[0]
-        args = [arg.replace('{}', filename) for arg in editor[1:]]
-        logging.debug("Calling \"{}\" with args {}".format(executable, args))
-        proc.start(executable, args)
+        editor = ExternalEditor()
+        editor.editing_finished.connect(self.on_editing_finished)
+        from qutebrowser.utils.debug import trace_lines; trace_lines(True)
+        editor.edit(text)
 
-    def _on_editor_cleanup(self, oshandle, filename):
-        os.close(oshandle)
-        try:
-            os.remove(filename)
-        except PermissionError:
-            message.error("Failed to delete tempfile...")
-
-    def on_editor_closed(self, elem, oshandle, filename, exitcode,
-                         exitstatus):
+    def on_editing_finished(self, text):
         """Write the editor text into the form field and clean up tempfile.
 
         Callback for QProcess when the editor was closed.
         """
-        logging.debug("Editor closed")
-        if exitcode != 0:
-            message.error("Editor did quit abnormally (status {})!".format(
-                exitcode))
-            return
-        if exitstatus != QProcess.NormalExit:
-            # No error here, since we already handle this in on_editor_error
-            return
         if elem.isNull():
             message.error("Element vanished while editing!")
             return
-        with open(filename, 'r') as f:
-            text = ''.join(f.readlines())
-            text = webelem.javascript_escape(text)
-        logging.debug("Read back: {}".format(text))
+        text = webelem.javascript_escape(text)
         elem.evaluateJavaScript("this.value='{}'".format(text))
-        self._on_editor_cleanup(oshandle, filename)
-
-    def on_editor_error(self, oshandle, filename, error):
-        """Display an error message and clean up when editor crashed."""
-        messages = {
-            QProcess.FailedToStart: "The process failed to start.",
-            QProcess.Crashed: "The process crashed.",
-            QProcess.Timedout: "The last waitFor...() function timed out.",
-            QProcess.WriteError: ("An error occurred when attempting to write "
-                                  "to the process."),
-            QProcess.ReadError: ("An error occurred when attempting to read "
-                                "from the process."),
-            QProcess.UnknownError: "An unknown error occurred.",
-        }
-        message.error("Error while calling editor: {}".format(messages[error]))
-        self._on_editor_cleanup(oshandle, filename)

qutebrowser/utils/misc.py

@@ -17,10 +17,17 @@
 
 """Other utilities which don't fit anywhere else."""
 
+import os
+import logging
 from functools import reduce
 from pkg_resources import resource_string
+from tempfile import mkstemp
+
+from PyQt5.QtCore import pyqtSignal, QProcess, QObject
 
 import qutebrowser
+import qutebrowser.config.config as config
+import qutebrowser.utils.message as message
 
 
 def read_file(filename):
@@ -46,3 +53,90 @@ def dotted_getattr(obj, path):
         The object at path.
     """
     return reduce(getattr, path.split('.'), obj)
+
+
+class ExternalEditor(QObject):
+
+    """Class to simplify editing a text in an external editor."""
+
+    editing_finished = pyqtSignal(str)
+
+    def __init__(self, parent=None):
+        super().__init__(parent)
+        self.text = None
+        self.oshandle = None
+        self.filename = None
+        self.proc = None
+
+    def _cleanup(self):
+        os.close(self.oshandle)
+        try:
+            os.remove(self.filename)
+        except PermissionError:
+            message.error("Failed to delete tempfile...")
+        self.text = None
+        self.oshandle = None
+        self.filename = None
+        self.proc = None
+
+    def on_proc_closed(self, exitcode, exitstatus):
+        """Write the editor text into the form field and clean up tempfile.
+
+        Callback for QProcess when the editor was closed.
+
+        Emit:
+            editing_finished: If process exited normally.
+        """
+        logging.debug("Editor closed")
+        if exitcode != 0:
+            message.error("Editor did quit abnormally (status {})!".format(
+                exitcode))
+            return
+        if exitstatus != QProcess.NormalExit:
+            # No error here, since we already handle this in on_editor_error
+            return
+        with open(self.filename, 'r') as f:
+            text = ''.join(f.readlines())
+        logging.debug("Read back: {}".format(text))
+        self._cleanup()
+        self.editing_finished.emit(text)
+
+    def on_proc_error(self, error):
+        """Display an error message and clean up when editor crashed."""
+        messages = {
+            QProcess.FailedToStart: "The process failed to start.",
+            QProcess.Crashed: "The process crashed.",
+            QProcess.Timedout: "The last waitFor...() function timed out.",
+            QProcess.WriteError: ("An error occurred when attempting to write "
+                                  "to the process."),
+            QProcess.ReadError: ("An error occurred when attempting to read "
+                                "from the process."),
+            QProcess.UnknownError: "An unknown error occurred.",
+        }
+        message.error("Error while calling editor: {}".format(messages[error]))
+        self._cleanup()
+
+    def edit(self, text):
+        """Edit a given text.
+
+        Args:
+            text: The initial text to edit.
+
+        Emit:
+            editing_finished with the new text if editing finshed successfully.
+        """
+        if self.text is not None:
+            raise ValueError("Already editing a file!")
+        self.text = text
+        self.oshandle, self.filename = mkstemp(text=True)
+        if not text:
+            with open(self.filename, 'w') as f:
+                f.write(text)
+        self.proc = QProcess(self)
+        self.proc.finished.connect(self.on_proc_closed)
+        self.proc.error.connect(self.on_proc_error)
+        editor = config.get('general', 'editor')
+        executable = editor[0]
+        args = [arg.replace('{}', self.filename) for arg in editor[1:]]
+        logging.debug("Calling \"{}\" with args {}".format(executable, args))
+        self.proc.start(executable, args)