Adding transpose lookup method. This will matrix transpose arrays that are…

Adding transpose lookup method. This will matrix transpose arrays that are passed in, and then work like items over the resulting list of lists. e.g.:

    Transpose a list of arrays:
    [1, 2, 3], [4, 5, 6] -> [1, 4], [2, 5], [3, 6]
    Replace any empty spots in 2nd array with "":
    [1, 2], [3] -> [1, 3], [2, ""]

lib/ansible/runner/lookup_plugins/transpose.py

+# (c) 2012, Michael DeHaan <michael.dehaan@gmail.com>
+#
+# This file is part of Ansible
+#
+# Ansible is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# Ansible is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
+
+import ansible.utils as utils
+from ansible.utils import safe_eval
+import ansible.errors as errors
+
+def flatten(terms):
+    ret = []
+    for term in terms:
+        if isinstance(term, list):
+            ret.extend(term)
+        elif isinstance(term, tuple):
+            ret.extend(term)
+        else:
+            ret.append(term)
+    return ret
+
+def transpose(a,b):
+    """
+    Transpose a list of arrays:
+    [1, 2, 3], [4, 5, 6] -> [1, 4], [2, 5], [3, 6]
+    Replace any empty spots in 2nd array with "":
+    [1, 2], [3] -> [1, 3], [2, ""]
+    """
+    results = []
+    for i in xrange(len(a)):
+        results.append([a[i], (b[i:i+1]+[""])[0]])
+    return results
+
+
+class LookupModule(object):
+
+    def __init__(self, basedir=None, **kwargs):
+        self.basedir = basedir
+
+    def __lookup_injects(self, terms, inject):
+        results = []
+        for x in terms:
+            if isinstance(x, basestring) and x in inject:
+                results.append(inject[x])
+            else:
+                results.append(x)
+        return results
+
+    def run(self, terms, inject=None, **kwargs):
+
+        # this code is common with 'items.py' consider moving to utils if we need it again
+
+        terms = utils.listify_lookup_plugin_terms(terms, self.basedir, inject)
+        terms = self.__lookup_injects(terms, inject)
+
+        my_list = terms[:]
+        my_list.reverse()
+        result = []
+        if len(my_list) == 0:
+            raise errors.AnsibleError("with_transpose requires at least one element in each list")
+        result = my_list.pop()
+        while len(my_list) > 0:
+            result2 = transpose(result, my_list.pop())
+            result  = result2
+        new_result = []
+        for x in result:
+            new_result.append(flatten(x))
+        return new_result
+
+