Fix tests on Python 2, and fix tests with DNSPython.

docs/changes/1012.bugfix

@@ -9,4 +9,5 @@ use modern Cython idioms.
 
 A few minor errors and discrepancies were fixed as well, such as
 ``gethostbyaddr(''localhost')`` working on Python 3 and failing on
-Python 2.
+Python 2. The DNSpython resolver now raises the expected TypeError in
+more cases instead of an AttributeError.

src/gevent/resolver/_addresses.py

@@ -142,9 +142,9 @@ def _ipv6_inet_aton(text,
 
 
 def _is_addr(host, parse=_ipv4_inet_aton):
-    if not host:
+    if not host or not isinstance(host, hostname_types):
         return False
-    assert isinstance(host, hostname_types), repr(host)
+
     try:
         parse(host)
     except AddressSyntaxError:
@@ -158,7 +158,7 @@ is_ipv4_addr = _is_addr
 
 def is_ipv6_addr(host):
     # Return True if host is a valid IPv6 address
-    if host:
+    if host and isinstance(host, hostname_types):
         s = '%' if isinstance(host, str) else b'%'
         host = host.split(s, 1)[0]
     return _is_addr(host, _ipv6_inet_aton)

src/gevent/resolver/ares.py

@@ -318,7 +318,7 @@ class Resolver(AbstractResolver):
                     raise
 
     def _getnameinfo(self, sockaddr, flags):
-        if not isinstance(flags, int):
+        if not isinstance(flags, integer_types):
             raise TypeError('an integer is required')
         if not isinstance(sockaddr, tuple):
             raise TypeError('getnameinfo() argument 1 must be a tuple')
@@ -331,7 +331,7 @@ class Resolver(AbstractResolver):
             raise TypeError('sockaddr[0] must be a string, not %s' % type(address).__name__)
 
         port = sockaddr[1]
-        if not isinstance(port, int):
+        if not isinstance(port, integer_types):
             raise TypeError('port must be an integer, not %s' % type(port))
 
         if len(sockaddr) > 2:
@@ -340,7 +340,7 @@ class Resolver(AbstractResolver):
             if flowinfo > 0xfffff:
                 raise OverflowError("getnameinfo(): flowinfo must be 0-1048575.")
 
-        result = self._getaddrinfo(address, str(sockaddr[1]),
+        result = self._getaddrinfo(address, port,
                                    family=AF_UNSPEC, socktype=SOCK_DGRAM, fill_in_type_proto=False)
         if len(result) != 1:
             raise error('sockaddr resolved to multiple addresses')

src/gevent/resolver/dnspython.py

@@ -393,13 +393,17 @@ class Resolver(AbstractResolver):
         aliases = self._resolver.hosts_resolver.getaliases(hostname)
         net_resolver = self._resolver.network_resolver
         rdtype = _family_to_rdtype(family)
-        while True:
+        while 1:
             try:
                 ans = net_resolver.query(hostname, dns.rdatatype.CNAME, rdtype)
             except (dns.resolver.NoAnswer, dns.resolver.NXDOMAIN, dns.resolver.NoNameservers):
                 break
             except dTimeout:
                 break
+            except AttributeError as ex:
+                if hostname is None or isinstance(hostname, int):
+                    raise TypeError(ex)
+                raise
             else:
                 aliases.extend(str(rr.target) for rr in ans.rrset)
                 hostname = ans[0].target