From 200e439a3051326d0c6a1191f89628aded094f40 Mon Sep 17 00:00:00 2001
From: Martin Tournoij <martin@arp242.net>
Date: Mon, 3 Apr 2017 02:29:38 +0100
Subject: [PATCH] Fix crash of :debug-log-filter when --filter wasn't given

There was no `LogFilter`. The fix is to always initialize a
`LogFilter()` with `None`. as the "filter".

Fixes #2303.
---
 CHANGELOG.asciidoc                      | 1 +
 qutebrowser/misc/utilcmds.py            | 9 ++++++---
 qutebrowser/utils/log.py                | 5 +++--
 tests/end2end/features/utilcmds.feature | 4 ++++
 4 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/CHANGELOG.asciidoc b/CHANGELOG.asciidoc
index 5f51fe822..74bf9e661 100644
--- a/CHANGELOG.asciidoc
+++ b/CHANGELOG.asciidoc
@@ -52,6 +52,7 @@ Fixed
 - Crash when pressing ctrl-c while a config error is shown
 - Crash when the key config isn't writable
 - Crash when unbinding an unbound key in the key config
+- Crash when using `:debug-log-filter` when `--filter` wasn't given on startup.
 - Various rare crashes
 
 v0.10.1
diff --git a/qutebrowser/misc/utilcmds.py b/qutebrowser/misc/utilcmds.py
index e617c1af2..1998e8341 100644
--- a/qutebrowser/misc/utilcmds.py
+++ b/qutebrowser/misc/utilcmds.py
@@ -295,13 +295,16 @@ def debug_log_filter(filters: str):
     Args:
         filters: A comma separated list of logger names.
     """
-    if set(filters.split(',')).issubset(log.LOGGER_NAMES):
-        log.console_filter.names = filters.split(',')
-    else:
+    if not set(filters.split(',')).issubset(log.LOGGER_NAMES):
         raise cmdexc.CommandError("filters: Invalid value {} - expected one "
                                   "of: {}".format(filters,
                                                   ', '.join(log.LOGGER_NAMES)))
 
+    if log.console_filter is None:
+        raise cmdexc.CommandError("No log.console_filter. Not attached "
+                                  "to a console?")
+    log.console_filter.names = filters.split(',')
+
 
 @cmdutils.register()
 @cmdutils.argument('current_win_id', win_id=True)
diff --git a/qutebrowser/utils/log.py b/qutebrowser/utils/log.py
index 7c96d4072..9c660f035 100644
--- a/qutebrowser/utils/log.py
+++ b/qutebrowser/utils/log.py
@@ -182,9 +182,10 @@ def init_log(args):
     root = logging.getLogger()
     global console_filter
     if console is not None:
+        console_filter = LogFilter(None)
         if args.logfilter is not None:
-            console_filter = LogFilter(args.logfilter.split(','))
-            console.addFilter(console_filter)
+            console_filter.names = args.logfilter.split(',')
+        console.addFilter(console_filter)
         root.addHandler(console)
     if ram is not None:
         root.addHandler(ram)
diff --git a/tests/end2end/features/utilcmds.feature b/tests/end2end/features/utilcmds.feature
index f9c43be98..aee57e053 100644
--- a/tests/end2end/features/utilcmds.feature
+++ b/tests/end2end/features/utilcmds.feature
@@ -164,3 +164,7 @@ Feature: Miscellaneous utility commands exposed to the user.
     Scenario: Using debug-log-filter with invalid filter
         When I run :debug-log-filter blah
         Then the error "filters: Invalid value blah - expected one of: statusbar, *" should be shown
+
+    Scenario: Using debug-log-filter
+        When I run :debug-log-filter webview
+        Then no crash should happen