sequence will now run once for start=end, added test to suite

fixes #11979

lib/ansible/plugins/lookup/sequence.py

@@ -142,13 +142,9 @@ class LookupModule(LookupBase):
 
     def sanity_check(self):
         if self.count is None and self.end is None:
-            raise AnsibleError(
+            raise AnsibleError( "must specify count or end in with_sequence")
-                "must specify count or end in with_sequence"
-            )
         elif self.count is not None and self.end is not None:
-            raise AnsibleError(
+            raise AnsibleError( "can't specify both count and end in with_sequence")
-                "can't specify both count and end in with_sequence"
-            )
         elif self.count is not None:
             # convert count to end
             if self.count != 0:
@@ -166,7 +162,7 @@ class LookupModule(LookupBase):
             raise AnsibleError("bad formatting string: %s" % self.format)
 
     def generate_sequence(self):
-        if self.stride > 0:
+        if self.stride >= 0:
             adjust = 1
         else:
             adjust = -1
@@ -187,8 +183,6 @@ class LookupModule(LookupBase):
         for term in terms:
             try:
                 self.reset()  # clear out things for this iteration
-
-                term = self._templar.template(term)
                 try:
                     if not self.parse_simple_args(term):
                         self.parse_kv_args(parse_kv(term))

test/integration/roles/test_iterators/tasks/main.yml

@@ -81,6 +81,11 @@
   with_sequence: count=0
   register: count_of_zero
 
+- name: test with_sequence does 1 when start == end
+  debug: msg='should run once'
+  with_sequence: start=1 end=1
+  register: start_equal_end
+
 - name: test with_sequence count 1
   set_fact: "{{ 'x' + item }}={{ item }}"
   with_sequence: count=1
@@ -88,6 +93,7 @@
 
 - assert:
     that:
+        - not start_equal_end| skipped
         - count_of_zero | skipped
         - not count_of_one | skipped
 
@@ -97,7 +103,7 @@
   set_fact: "random={{ item }}"
   with_random_choice:
     - "foo"
-    - "bar" 
+    - "bar"
 
 - name: verify with_random_choice
   assert: