Added chicken and egg recursion detection

src/core/builtin_helpers.py

@@ -4,7 +4,6 @@ import logging
 import core.ast.nodes
 from core.ast.nodes import CallNodeConcept, GenericNodeConcept
 from core.ast.visitors import UnreferencedNamesVisitor
-
 from core.builtin_concepts import BuiltinConcepts
 
 
@@ -100,11 +99,22 @@ def expect_one(context, return_values, logger=None):
             return_values[0],
             parents=return_values)
     else:
-        return sheerka.ret(
-            context.who,
-            False,
-            sheerka.new(BuiltinConcepts.TOO_MANY_ERRORS, body=return_values),
-            parents=return_values)
+        # test if only one evaluator in error
+        from evaluators.OneErrorEvaluator import OneErrorEvaluator
+        one_error_evaluator = OneErrorEvaluator()
+        reduce_requested = sheerka.ret(context.who, True, sheerka.new(BuiltinConcepts.REDUCE_REQUESTED))
+        if one_error_evaluator.matches(context, return_values + [reduce_requested]):
+            return sheerka.ret(
+                context.who,
+                False,
+                one_error_evaluator.eval(context, return_values).body,
+                parents=return_values)
+        else:
+            return sheerka.ret(
+                context.who,
+                False,
+                sheerka.new(BuiltinConcepts.TOO_MANY_ERRORS, body=return_values),
+                parents=return_values)
 
 
 def get_names(sheerka, concept_node):
@@ -210,5 +220,3 @@ def _extract_predicates(sheerka, node, variables_to_include, variables_to_exclud
                 predicates.append(res)
 
     return predicates
-
-