reformated test, changed big assert to with_items

much easier to see the individual condition that causes the failure
when using with_items and evaluating each part of the assert individually

test/integration/test_var_precedence.yml

@@ -1,6 +1,7 @@
 ---
 - hosts: testhost
   vars:
+    - ansible_hostname: "BAD!"
     - vars_var: "vars_var"
     - param_var: "BAD!"
     - vars_files_var: "BAD!"
@@ -24,7 +25,8 @@
     - debug: var=registered_var
     - debug: var=from_inventory_once_removed
     - assert:
-      that:
+        that: item
+      with_items:
           - 'extra_var == "extra_var"'
           - 'extra_var_override == "extra_var_override"'
           - 'extra_var_override_once_removed == "extra_var_override"'