Clean up :messages implementation.

- Add log.LOG_LEVELS to map names to levels (instead of using
  logging._levelToName)
- Test that log pages do not contain messages below the requested level
- Use pythons urllib.parse.parse_qs instead of Qt's UrlQuery
- Document tab, bg, window args for :messages
- Clean up style

qutebrowser/browser/commands.py

@@ -1348,7 +1348,12 @@ class CommandDispatcher:
             level: Include messages with `level` or higher severity.
                    Valid values: vdebug, debug, info, warning, error, critical.
             plain: Whether to show plaintext (as opposed to html).
+            tab: Open in a new tab.
+            bg: Open in a background tab.
+            window: Open in a new window.
         """
+        if level.upper() not in log.LOG_LEVELS:
+            raise cmdexc.CommandError("Invalid log level {}!".format(level))
         if plain:
             url = QUrl('qute://plainlog?level={}'.format(level))
         else:

qutebrowser/browser/network/qutescheme.py

@@ -26,8 +26,9 @@ Module attributes:
 import functools
 import configparser
 import mimetypes
+import urllib.parse
 
-from PyQt5.QtCore import pyqtSlot, QObject, QUrlQuery
+from PyQt5.QtCore import pyqtSlot, QObject
 from PyQt5.QtNetwork import QNetworkReply
 
 import qutebrowser
@@ -158,36 +159,34 @@ def qute_version(_win_id, _request):
 
 
 @add_handler('plainlog')
-def qute_plainlog(_win_id, _request):
+def qute_plainlog(_win_id, request):
     """Handler for qute:plainlog. Return HTML content as bytes.
 
-    An optional query parameter specifies the min log level to print.
+    An optional query parameter specifies the minimum log level to print.
     For example, qute://log?level=warning prints warnings and errors.
     Level can be one of: vdebug, debug, info, warning, error, critical.
     """
     if log.ram_handler is None:
         text = "Log output was disabled."
     else:
-        query = QUrlQuery(_request.url().query())
-        level = query.queryItemValue('level')
+        level = urllib.parse.parse_qs(request.url().query()).get('level')[0]
         text = log.ram_handler.dump_log(html=False, level=level)
     html = jinja.render('pre.html', title='log', content=text)
     return html.encode('UTF-8', errors='xmlcharrefreplace')
 
 
 @add_handler('log')
-def qute_log(_win_id, _request):
+def qute_log(_win_id, request):
     """Handler for qute:log. Return HTML content as bytes.
 
-    An optional query parameter specifies the min log level to print.
+    An optional query parameter specifies the minimum log level to print.
     For example, qute://log?level=warning prints warnings and errors.
     Level can be one of: vdebug, debug, info, warning, error, critical.
     """
     if log.ram_handler is None:
         html_log = None
     else:
-        query = QUrlQuery(_request.url().query())
-        level = query.queryItemValue('level')
+        level = urllib.parse.parse_qs(request.url().query()).get('level')[0]
         html_log = log.ram_handler.dump_log(html=True, level=level)
 
     html = jinja.render('log.html', title='log', content=html_log)

qutebrowser/utils/log.py

@@ -64,13 +64,21 @@ LOG_COLORS = {
     'CRITICAL': 'red',
 }
 
-
 # We first monkey-patch logging to support our VDEBUG level before getting the
 # loggers.  Based on http://stackoverflow.com/a/13638084
 VDEBUG_LEVEL = 9
 logging.addLevelName(VDEBUG_LEVEL, 'VDEBUG')
 logging.VDEBUG = VDEBUG_LEVEL
 
+LOG_LEVELS = {
+    'VDEBUG': logging.VDEBUG,
+    'DEBUG': logging.DEBUG,
+    'INFO': logging.INFO,
+    'WARNING': logging.WARNING,
+    'ERROR': logging.ERROR,
+    'CRITICAL': logging.CRITICAL,
+}
+
 
 def vdebug(self, msg, *args, **kwargs):
     """Log with a VDEBUG level.
@@ -436,8 +444,7 @@ class RAMHandler(logging.Handler):
         (probably obsolete when moving to a widget for logging,
         https://github.com/The-Compiler/qutebrowser/issues/34
         """
-        # pylint: disable=protected-access
-        minlevel = logging._nameToLevel.get(level.upper(), VDEBUG_LEVEL)
+        minlevel = LOG_LEVELS.get(level.upper(), VDEBUG_LEVEL)
         lines = []
         fmt = self.html_formatter.format if html else self.format
         self.acquire()

tests/integration/features/conftest.py

@@ -368,7 +368,7 @@ def check_contents_plain(quteproc, text):
 
 @bdd.then(bdd.parsers.parse('the page should not contain the plaintext '
                             '"{text}"'))
-def check_contents_plain(quteproc, text):
+def check_not_contents_plain(quteproc, text):
     """Check the current page's content based on a substring."""
     content = quteproc.get_content().strip()
     assert text not in content

tests/integration/features/misc.feature

@@ -378,6 +378,8 @@ Feature: Various utility commands.
         Then the error "the-error-message" should be shown
         And the warning "the-warning-message" should be shown
         And the page should contain the plaintext "the-error-message"
+        And the page should not contain the plaintext "the-warning-message"
+        And the page should not contain the plaintext "the-info-message"
 
     Scenario: Showing messages of type 'warning' or greater
         When I run :message-error the-error-message
@@ -388,6 +390,7 @@ Feature: Various utility commands.
         And the warning "the-warning-message" should be shown
         And the page should contain the plaintext "the-error-message"
         And the page should contain the plaintext "the-warning-message"
+        And the page should not contain the plaintext "the-info-message"
 
     Scenario: Showing messages of type 'info' or greater
         When I run :message-error the-error-message
@@ -399,3 +402,7 @@ Feature: Various utility commands.
         And the page should contain the plaintext "the-error-message"
         And the page should contain the plaintext "the-warning-message"
         And the page should contain the plaintext "the-info-message"
+
+    Scenario: Showing messages of an invalid level
+        When I run :messages cataclysmic
+        Then the error "Invalid log level cataclysmic!" should be shown