configdata: Make sure default values are valid

qutebrowser/config/configdata.yml

@@ -76,7 +76,7 @@ editor.command:
   type:
     name: ShellCommand
     placeholder: true
-  default: "gvim -f '{}'"
+  default: ["gvim", "-f", "{}"]
   desc: >-
     The editor (and arguments) to use for the `open-editor` command.
 

tests/unit/config/test_configdata.py

@@ -28,10 +28,12 @@ from qutebrowser.utils import usertypes
 
 
 def test_init():
-    """Test reading the default yaml file."""
+    """Test reading the default yaml file and validating the values."""
     configdata.init()
     assert isinstance(configdata.DATA, dict)
     assert 'ignore_case' in configdata.DATA
+    for option in configdata.DATA.values():
+        option.typ.from_py(option.default)
 
 
 def test_init_benchmark(benchmark):
@@ -40,7 +42,6 @@ def test_init_benchmark(benchmark):
 
 class TestReadYaml:
 
-
     def test_valid(self):
         data = textwrap.dedent("""
             test1: