Ensure rules evaluation does something sensible with empty values and Nones.

Author: acerathereinspirative-nhs-nvir

src/eligibility_signposting_api/services/eligibility_services.py

@@ -87,13 +87,13 @@ def evaluate_rule(iteration_rule: IterationRule, attribute_value: Any) -> bool:
             case RuleOperator.ne:
                 return attribute_value != iteration_rule.comparator
             case RuleOperator.lt:
-                return int(attribute_value) < int(iteration_rule.comparator)
+                return int(attribute_value or 0) < int(iteration_rule.comparator)
             case RuleOperator.lte:
-                return int(attribute_value) <= int(iteration_rule.comparator)
+                return int(attribute_value or 0) <= int(iteration_rule.comparator)
             case RuleOperator.gt:
-                return int(attribute_value) > int(iteration_rule.comparator)
+                return int(attribute_value or 0) > int(iteration_rule.comparator)
             case RuleOperator.gte:
-                return int(attribute_value) >= int(iteration_rule.comparator)
+                return int(attribute_value or 0) >= int(iteration_rule.comparator)
             case RuleOperator.year_gt:
                 attribute_date = datetime.strptime(str(attribute_value), "%Y%m%d") if attribute_value else None  # noqa: DTZ007
                 today = datetime.today()  # noqa: DTZ002

tests/unit/services/test_eligibility_services.py

@@ -162,12 +162,16 @@ def test_equals_rule():
     rule = IterationRuleFactory.build(operator=RuleOperator.equals, comparator="42")
     assert EligibilityService.evaluate_rule(rule, "42")
     assert not EligibilityService.evaluate_rule(rule, "99")
+    assert not EligibilityService.evaluate_rule(rule, "")
+    assert not EligibilityService.evaluate_rule(rule, None)
 
 
 def test_not_equals_rule():
     rule = IterationRuleFactory.build(operator=RuleOperator.ne, comparator="42")
     assert EligibilityService.evaluate_rule(rule, "99")
     assert not EligibilityService.evaluate_rule(rule, "42")
+    assert EligibilityService.evaluate_rule(rule, "")
+    assert EligibilityService.evaluate_rule(rule, None)
 
 
 def test_less_than_rule():
@@ -176,27 +180,35 @@ def test_less_than_rule():
     assert EligibilityService.evaluate_rule(rule, "99")
     assert not EligibilityService.evaluate_rule(rule, "100")
     assert not EligibilityService.evaluate_rule(rule, "101")
+    assert EligibilityService.evaluate_rule(rule, "")
+    assert EligibilityService.evaluate_rule(rule, None)
 
 
 def test_less_than_or_equal_rule():
     rule = IterationRuleFactory.build(operator=RuleOperator.lte, comparator="100")
     assert EligibilityService.evaluate_rule(rule, "99")
     assert EligibilityService.evaluate_rule(rule, "100")
     assert not EligibilityService.evaluate_rule(rule, "101")
+    assert EligibilityService.evaluate_rule(rule, "")
+    assert EligibilityService.evaluate_rule(rule, None)
 
 
 def test_greater_than_rule():
     rule = IterationRuleFactory.build(operator=RuleOperator.gt, comparator="100")
     assert EligibilityService.evaluate_rule(rule, "101")
     assert not EligibilityService.evaluate_rule(rule, "100")
     assert not EligibilityService.evaluate_rule(rule, "99")
+    assert not EligibilityService.evaluate_rule(rule, "")
+    assert not EligibilityService.evaluate_rule(rule, None)
 
 
 def test_greater_than_or_equal_rule():
     rule = IterationRuleFactory.build(operator=RuleOperator.gte, comparator="100")
     assert EligibilityService.evaluate_rule(rule, "100")
     assert EligibilityService.evaluate_rule(rule, "101")
     assert not EligibilityService.evaluate_rule(rule, "99")
+    assert not EligibilityService.evaluate_rule(rule, "")
+    assert not EligibilityService.evaluate_rule(rule, None)
 
 
 def test_year_gt_rule_future_date():
@@ -206,6 +218,8 @@ def test_year_gt_rule_future_date():
     attribute_value = future_date.strftime("%Y%m%d")
     rule = IterationRuleFactory.build(operator=RuleOperator.year_gt, comparator=str(years_offset))
     assert EligibilityService.evaluate_rule(rule, attribute_value)
+    assert not EligibilityService.evaluate_rule(rule, "")
+    assert not EligibilityService.evaluate_rule(rule, None)
 
 
 def test_year_gt_rule_past_date():
@@ -215,12 +229,8 @@ def test_year_gt_rule_past_date():
     attribute_value = past_date.strftime("%Y%m%d")
     rule = IterationRuleFactory.build(operator=RuleOperator.year_gt, comparator=str(years_offset))
     assert not EligibilityService.evaluate_rule(rule, attribute_value)
-
-
-def test_year_gt_rule_empty_value():
-    rule = IterationRuleFactory.build(operator=RuleOperator.year_gt, comparator="2")
-    assert not EligibilityService.evaluate_rule(rule, None)
     assert not EligibilityService.evaluate_rule(rule, "")
+    assert not EligibilityService.evaluate_rule(rule, None)
 
 
 def test_unimplemented_operator():