LHS assignment expressions didn't work with non-trivial indexation

Most of assignment expressions involving indexation operator except
for the most trivial one fail.

For example the following failed:

$myDict[$keyName]: value
$myDict['A']['B']: value (even if $myDict['A'] is a dictionary)
$myList[2 + 2]: value
$myList[$index]: value

This commit adds support for sub-expressions within LHS-expressions

Change-Id: I4b72e85b5f9bda04c6156d5c8b07eb8f5358643d
Closes-Bug: #1358545

murano/dsl/lhs_expression.py

@@ -45,7 +45,14 @@ class LhsExpression(object):
         self._current_obj_name = None
 
     def _create_context(self, root_context, murano_class):
+        def _evaluate(thing):
+            if isinstance(thing, yaql.expressions.Expression.Callable):
+                thing.yaql_context = root_context
+                thing = thing()
+            return thing
+
         def _get_value(src, key):
+            key = _evaluate(key)
             if isinstance(src, types.DictionaryType):
                 return src.get(key)
             elif isinstance(src, types.ListType) and isinstance(
@@ -60,6 +67,7 @@ class LhsExpression(object):
                 raise TypeError()
 
         def _set_value(src, key, value):
+            key = _evaluate(key)
             if isinstance(src, types.DictionaryType):
                 old_value = src.get(key, type_scheme.NoValue)
                 src[key] = value
@@ -115,9 +123,11 @@ class LhsExpression(object):
 
         @yaql.context.EvalArg("this", LhsExpression.Property)
         def indexation(this, index):
+            index = _evaluate(index)
+
             return LhsExpression.Property(
-                lambda: _get_value(this.get(), index()),
-                lambda value: _set_value(this.get(), index(), value))
+                lambda: _get_value(this.get(), index),
+                lambda value: _set_value(this.get(), index, value))
 
         context = yaql.context.Context()
         context.register_function(get_context_data, '#get_context_data')

murano/tests/unit/dsl/meta/SampleClass1.yaml

@@ -45,12 +45,23 @@ Workflow:
       - $x: $.getAttr(att1)
       - $y: $.getAttr(att2, ' Doe')
       - Return: $x + $y
+
   testAssignment:
     Body:
-      - $x: {}
-      - $x.A: [1, 2]
-      - $x.A[0]: 3
-      - Return: $x
+      - $result: {}
+      - $result.Arr: [1, 2, [10, 11]]
+      - $index: 1
+      - $result.Arr[0]: 3
+      - $result.Arr[$index - 1]: 5
+      - $result.Arr[$index + 1][1]: 123
+      - $result.Dict: {}
+      - $result.Dict.Key1: V1
+      - $keyName: Key2
+      - $result.Dict[$keyName]: {}
+      - $result.Dict[$keyName]['a_b']: V2
+      - $result.Dict[$keyName][toUpper($keyName)]: V3
+      - Return: $result
+
 
   testAssignByCopy:
     Arguments:

murano/tests/unit/dsl/test_assignments.py

@@ -29,8 +29,13 @@ class TestAssignments(test_case.DslTestCase):
 
     def test_assignment(self):
         self.assertEqual(
-            {'A': [3, 2]},
-            self._runner.testAssignment())
+            {
+                'Arr': [5, 2, [10, 123]],
+                'Dict': {
+                    'Key1': 'V1',
+                    'Key2': {'KEY2': 'V3', 'a_b': 'V2'}
+                }
+            }, self._runner.testAssignment())
 
     def test_assign_by_copy(self):
         self.assertEqual(