implemented inventory_hostname lookup in v2

lib/ansible/plugins/lookup/inventory_hostnames.py

@@ -21,18 +21,35 @@ __metaclass__ = type
 
 from ansible.errors import *
 from ansible.plugins.lookup import LookupBase
+from ansible.inventory import Inventory
 
 class LookupModule(LookupBase):
 
-    def run(self, terms, inject=None, **kwargs):
-        ### FIXME: Is this needed now that listify is run on all lookup plugin terms?
-        if not isinstance(terms, list):
-            raise AnsibleError("with_inventory_hostnames expects a list")
+    def get_hosts(self, variables, pattern):
+        #print(variables)
+        #print(variables['groups'])
+        hosts = []
+        if pattern in variables['groups']:
+            hosts = variables['groups'][pattern]
+        elif pattern in variables['groups']['all']:
+            hosts = [pattern]
+        return hosts
 
-        # FIXME: the inventory is no longer available this way, so we may have
-        #        to dump the host list into the list of variables and read it back
-        #        in here (or the inventory sources, so we can recreate the list
-        #        of hosts)
-        #return self._flatten(inventory.Inventory(self.host_list).list_hosts(terms))
-        return terms
+    def run(self, terms, variables=None, **kwargs):
 
+        host_list = []
+
+        for term in terms:
+            patterns = Inventory.order_patterns(Inventory.split_host_pattern(term))
+
+            for p in patterns:
+                that = self.get_hosts(variables, p)
+                if p.startswith("!"):
+                    host_list = [ h for h in host_list if h not in that]
+                elif p.startswith("&"):
+                    host_list = [ h for h in host_list if h in that ]
+                else:
+                    host_list.extend(that)
+
+        # return unique list
+        return list(set(host_list))