From 0ef5d338bdf90821daac7a6ebd6339bda7b6ad7e Mon Sep 17 00:00:00 2001
From: Daniel Schadt <kingdread@gmx.de>
Date: Thu, 15 Sep 2016 15:44:33 +0200
Subject: [PATCH 1/4] make sure keyword-only arguments have a default

Fixes #1872.

This prevents inspect.Parameter.empty from slipping through to the
command.
---
 qutebrowser/commands/command.py      |  4 ++++
 tests/unit/commands/test_cmdutils.py | 18 ++++++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/qutebrowser/commands/command.py b/qutebrowser/commands/command.py
index ea1d0d46b..ce9e26eb8 100644
--- a/qutebrowser/commands/command.py
+++ b/qutebrowser/commands/command.py
@@ -246,6 +246,10 @@ class Command:
                     continue
                 if self._inspect_special_param(param):
                     continue
+                if (param.kind == inspect.Parameter.KEYWORD_ONLY and
+                      param.default is inspect.Parameter.empty):
+                    raise TypeError("{}: handler has keyword only argument "
+                                    "without default!".format(self.name))
                 typ = self._get_type(param)
                 is_bool = typ is bool
                 kwargs = self._param_to_argparse_kwargs(param, is_bool)
diff --git a/tests/unit/commands/test_cmdutils.py b/tests/unit/commands/test_cmdutils.py
index 917b94e3e..1aacf3c33 100644
--- a/tests/unit/commands/test_cmdutils.py
+++ b/tests/unit/commands/test_cmdutils.py
@@ -349,6 +349,24 @@ class TestRegister:
         with pytest.raises(IndexError):
             cmd.get_pos_arg_info(2)
 
+    def test_keyword_only_without_default(self):
+        # https://github.com/The-Compiler/qutebrowser/issues/1872
+        def fun(*, target):
+            """Blah."""
+            pass
+
+        with pytest.raises(TypeError):
+            fun = cmdutils.register()(fun)
+
+    def test_typed_keyword_only_without_default(self):
+        # https://github.com/The-Compiler/qutebrowser/issues/1872
+        def fun(*, target: int):
+            """Blah."""
+            pass
+
+        with pytest.raises(TypeError):
+            fun = cmdutils.register()(fun)
+
 
 class TestArgument:
 

From b6d9d3f955b8b50c22bec765c6a3800508de401d Mon Sep 17 00:00:00 2001
From: Daniel Schadt <kingdread@gmx.de>
Date: Thu, 15 Sep 2016 15:46:26 +0200
Subject: [PATCH 2/4] fix tests for new "default required" policy

This test had a keyword only parameter without a default, which is now
disallowed. This caused the test to fail.
---
 tests/unit/commands/test_cmdutils.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/unit/commands/test_cmdutils.py b/tests/unit/commands/test_cmdutils.py
index 1aacf3c33..6f533798f 100644
--- a/tests/unit/commands/test_cmdutils.py
+++ b/tests/unit/commands/test_cmdutils.py
@@ -324,7 +324,7 @@ class TestRegister:
         # https://github.com/The-Compiler/qutebrowser/issues/1871
         @cmdutils.register()
         @cmdutils.argument('arg', choices=['foo', 'bar'])
-        def fun(*, arg):
+        def fun(*, arg='foo'):
             """Blah."""
             pass
 

From 794eb84805394a5f2540aa1de6279b8286ff976e Mon Sep 17 00:00:00 2001
From: Daniel Schadt <kingdread@gmx.de>
Date: Thu, 15 Sep 2016 16:38:18 +0200
Subject: [PATCH 3/4] add parameter name in error message

---
 qutebrowser/commands/command.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/qutebrowser/commands/command.py b/qutebrowser/commands/command.py
index ce9e26eb8..ff4b2768a 100644
--- a/qutebrowser/commands/command.py
+++ b/qutebrowser/commands/command.py
@@ -247,9 +247,10 @@ class Command:
                 if self._inspect_special_param(param):
                     continue
                 if (param.kind == inspect.Parameter.KEYWORD_ONLY and
-                      param.default is inspect.Parameter.empty):
+                        param.default is inspect.Parameter.empty):
                     raise TypeError("{}: handler has keyword only argument "
-                                    "without default!".format(self.name))
+                                    "{!r} without default!".format(self.name,
+                                                                   param.name))
                 typ = self._get_type(param)
                 is_bool = typ is bool
                 kwargs = self._param_to_argparse_kwargs(param, is_bool)

From eabfdb3c165b133b666f222b1f2f8147f4bf650c Mon Sep 17 00:00:00 2001
From: Daniel Schadt <kingdread@gmx.de>
Date: Thu, 15 Sep 2016 16:42:02 +0200
Subject: [PATCH 4/4] tests: make sure the type error is the one we want

---
 tests/unit/commands/test_cmdutils.py | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/tests/unit/commands/test_cmdutils.py b/tests/unit/commands/test_cmdutils.py
index 6f533798f..f672a6768 100644
--- a/tests/unit/commands/test_cmdutils.py
+++ b/tests/unit/commands/test_cmdutils.py
@@ -355,18 +355,27 @@ class TestRegister:
             """Blah."""
             pass
 
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError) as excinfo:
             fun = cmdutils.register()(fun)
 
+        expected = ("fun: handler has keyword only argument 'target' without "
+                    "default!")
+        assert str(excinfo.value) == expected
+
+
     def test_typed_keyword_only_without_default(self):
         # https://github.com/The-Compiler/qutebrowser/issues/1872
         def fun(*, target: int):
             """Blah."""
             pass
 
-        with pytest.raises(TypeError):
+        with pytest.raises(TypeError) as excinfo:
             fun = cmdutils.register()(fun)
 
+        expected = ("fun: handler has keyword only argument 'target' without "
+                    "default!")
+        assert str(excinfo.value) == expected
+
 
 class TestArgument: