Body Editing Fixes (#4853)

* clarify that `IS_WINDOWS` includes WSL

* windows: fix file editing

tornado's asnycio patch does not take nonexisting file descriptors very well,
so we need to catch errors here.

* body editing: better editor guessing, fix #4798

mitmproxy/contrib/urwid/raw_display.py

@@ -444,7 +444,10 @@ class Screen(BaseScreen, RealTerminal):
             self._input_thread = None
 
         for handle in self._current_event_loop_handles:
-            event_loop.remove_watch_file(handle)
+            try:
+                event_loop.remove_watch_file(handle)
+            except KeyError:
+                pass
 
         if self._input_timeout:
             event_loop.remove_alarm(self._input_timeout)

mitmproxy/tools/console/common.py

@@ -14,7 +14,7 @@ from mitmproxy.utils import human, emoji
 from mitmproxy.tcp import TCPFlow
 
 # Detect Windows Subsystem for Linux and Windows
-IS_WINDOWS = "Microsoft" in platform.platform() or "Windows" in platform.platform()
+IS_WINDOWS_OR_WSL = "Microsoft" in platform.platform() or "Windows" in platform.platform()
 
 
 def is_keypress(k):

mitmproxy/tools/console/master.py

@@ -4,6 +4,7 @@ import mimetypes
 import os
 import os.path
 import shlex
+import shutil
 import signal
 import stat
 import subprocess
@@ -24,7 +25,6 @@ from mitmproxy.addons import intercept
 from mitmproxy.addons import eventstore
 from mitmproxy.addons import readfile
 from mitmproxy.addons import view
-from mitmproxy.tools.console import common
 from mitmproxy.tools.console import consoleaddons
 from mitmproxy.tools.console import defaultkeys
 from mitmproxy.tools.console import keymap
@@ -116,13 +116,26 @@ class ConsoleMaster(master.Master):
             self.loop.screen_size = None
             self.loop.draw_screen()
 
+    def get_editor(self) -> str:
+        # based upon https://github.com/pallets/click/blob/main/src/click/_termui_impl.py
+        if m := os.environ.get("MITMPROXY_EDITOR"):
+            return m
+        if m := os.environ.get("EDITOR"):
+            return m
+        for editor in "sensible-editor", "nano", "vim":
+            if shutil.which(editor):
+                return editor
+        if os.name == "nt":
+            return "notepad"
+        else:
+            return "vi"
+
     def spawn_editor(self, data):
         text = not isinstance(data, bytes)
-        fd, name = tempfile.mkstemp('', "mproxy", text=text)
+        fd, name = tempfile.mkstemp('', "mitmproxy", text=text)
         with open(fd, "w" if text else "wb") as f:
             f.write(data)
-        # if no EDITOR is set, assume 'vi'
-        c = os.environ.get("MITMPROXY_EDITOR") or os.environ.get("EDITOR") or "vi"
+        c = self.get_editor()
         cmd = shlex.split(c)
         cmd.append(name)
         with self.uistopped():
@@ -203,7 +216,7 @@ class ConsoleMaster(master.Master):
             ["console_palette", "console_palette_transparent"]
         )
         loop = asyncio.get_event_loop()
-        if common.IS_WINDOWS:
+        if isinstance(loop, getattr(asyncio, "ProactorEventLoop", tuple())):
             # fix for https://bugs.python.org/issue37373
             loop = AddThreadSelectorEventLoop(loop)
         self.loop = urwid.MainLoop(

mitmproxy/tools/console/window.py

@@ -324,7 +324,7 @@ class Window(urwid.Frame):
 class Screen(raw_display.Screen):
 
     def write(self, data):
-        if common.IS_WINDOWS:
+        if common.IS_WINDOWS_OR_WSL:
             # replace urwid's SI/SO, which produce artifacts under WSL.
             # at some point we may figure out what they actually do.
             data = re.sub("[\x0e\x0f]", "", data)