Add unit tests for help completion.

Also adds a FakeConfigSection stub for stubbing out configdata.DATA.

tests/helpers/stubs.py

@@ -340,6 +340,22 @@ class FakeTimer(QObject):
         return self._started
 
 
+class FakeConfigSection:
+
+    """A stub for a KeyValue entry in configdata.DATA."""
+
+    def __init__(self, *entries):
+        self.values = []
+        self.descriptions = {}
+        for name, desc in entries:
+            self.values.append(name)
+            self.descriptions[name] = desc
+
+    def __iter__(self):
+        """Iterate over all set values."""
+        return self.values.__iter__()
+
+
 class ConfigStub(QObject):
 
     """Stub for the config module.

tests/unit/completion/test_models.py

@@ -19,6 +19,8 @@
 
 """Tests for completion models."""
 
+import collections
+
 from qutebrowser.completion.models import miscmodels
 
 
@@ -47,6 +49,37 @@ def test_command_completion(monkeypatch, stubs, config_stub, key_config_stub):
     ]
 
 
+def test_help_completion(monkeypatch, stubs):
+    """Test the results of command completion.
+
+    Validates that:
+        - only non-hidden and non-deprecated commands are included
+        - commands are sorted by name
+        - the command description is shown in the desc column
+        - the binding (if any) is shown in the misc column
+        - aliases are included
+        - only the first line of a multiline description is shown
+    """
+    module = 'qutebrowser.completion.models.miscmodels'
+    _patch_cmdutils(monkeypatch, stubs, module + '.cmdutils')
+    _patch_configdata(monkeypatch, stubs, module + '.configdata.DATA')
+    actual = _get_completions(miscmodels.HelpCompletionModel())
+    assert actual == [
+        ("Commands", [
+            (':drop', 'drop all user data', ''),
+            (':roll', 'never gonna give you up', ''),
+            (':stop', 'stop qutebrowser', '')
+        ]),
+        ("Settings", [
+            ('general->time', 'Is an illusion.', ''),
+            ('general->volume', 'Goes to 11', ''),
+            ('ui->gesture', 'Waggle your hands to control qutebrowser', ''),
+            ('ui->mind', 'Enable mind-control ui (experimental)', ''),
+            ('ui->voice', 'Whether to respond to voice commands', ''),
+        ])
+    ]
+
+
 def _get_completions(model):
     """Collect all the completion entries of a model, organized by category.
 
@@ -80,3 +113,17 @@ def _patch_cmdutils(monkeypatch, stubs, symbol):
         'depr': stubs.FakeCommand(name='depr', deprecated=True),
     })
     monkeypatch.setattr(symbol, cmd_utils)
+
+
+def _patch_configdata(monkeypatch, stubs, symbol):
+    """Patch the configdata module to provide fake data."""
+    data = collections.OrderedDict([
+        ('general', stubs.FakeConfigSection(
+            ('time', 'Is an illusion.\n\nLunchtime doubly so.'),
+            ('volume', 'Goes to 11'))),
+        ('ui', stubs.FakeConfigSection(
+            ('gesture', 'Waggle your hands to control qutebrowser'),
+            ('mind', 'Enable mind-control ui (experimental)'),
+            ('voice', 'Whether to respond to voice commands'))),
+    ])
+    monkeypatch.setattr(symbol, data)