py3++, multidict fixes

This commit improves Python 3 compatibility and fixes two multidict
issues:

 1. Headers.items(multi=True) now decodes fields
 2. MultiDict.clear(item) has been removed, as Python's
    MutableMapping already defines .clear() with different
    semantics. This is confusing for everyone who expects a
    dict-like object. `.pop("attr", None)` is not fantastic,
    but it's the Python way to do it.

3 files changed, 19 insertions, 20 deletions

diff --git a/netlib/http/headers.py b/netlib/http/headers.py
index f052a53b..413add87 100644
--- a/netlib/http/headers.py
+++ b/netlib/http/headers.py
@@ -148,6 +148,15 @@ class Headers(multidict.MultiDict):
         value = _always_bytes(value)
         super(Headers, self).insert(index, key, value)
 
+    def items(self, multi=False):
+        if multi:
+            return (
+                (_native(k), _native(v))
+                for k, v in self.fields
+            )
+        else:
+            return super(Headers, self).items()
+
     def replace(self, pattern, repl, flags=0):
         """
         Replaces a regular expression pattern with repl in each "name: value"
diff --git a/netlib/http/http2/utils.py b/netlib/http/http2/utils.py
index 4c01952d..164bacc8 100644
--- a/netlib/http/http2/utils.py
+++ b/netlib/http/http2/utils.py
@@ -7,9 +7,9 @@ def parse_headers(headers):
     scheme = headers.get(':scheme', 'https').encode()
     path = headers.get(':path', '/').encode()
 
-    headers.clear(":method")
-    headers.clear(":scheme")
-    headers.clear(":path")
+    headers.pop(":method", None)
+    headers.pop(":scheme", None)
+    headers.pop(":path", None)
 
     host = None
     port = None
diff --git a/netlib/multidict.py b/netlib/multidict.py
index 50c879d9..51053ff6 100644
--- a/netlib/multidict.py
+++ b/netlib/multidict.py
@@ -170,18 +170,10 @@ class _MultiDict(MutableMapping, basetypes.Serializable):
         else:
             return super(_MultiDict, self).items()
 
-    def clear(self, key):
-        """
-            Removes all items with the specified key, and does not raise an
-            exception if the key does not exist.
-        """
-        if key in self:
-            del self[key]
-
     def collect(self):
         """
             Returns a list of (key, value) tuples, where values are either
-            singular if threre is only one matching item for a key, or a list
+            singular if there is only one matching item for a key, or a list
             if there are more than one. The order of the keys matches the order
             in the underlying fields list.
         """
@@ -204,18 +196,16 @@ class _MultiDict(MutableMapping, basetypes.Serializable):
         .. code-block:: python
 
             # Simple dict with duplicate values.
-            >>> d
-            MultiDictView[("name", "value"), ("a", "false"), ("a", "42")]
+            >>> d = MultiDict([("name", "value"), ("a", False), ("a", 42)])
             >>> d.to_dict()
             {
                 "name": "value",
-                "a": ["false", "42"]
+                "a": [False, 42]
             }
         """
-        d = {}
-        for k, v in self.collect():
-            d[k] = v
-        return d
+        return {
+            k: v for k, v in self.collect()
+        }
 
     def get_state(self):
         return self.fields
@@ -307,4 +297,4 @@ class MultiDictView(_MultiDict):
 
     @fields.setter
     def fields(self, value):
-        return self._setter(value)
+        self._setter(value)