feat: update logic for deterministic rules for nested fields (#1524)

Author: dianapirvulescu

packages/uipath-core/pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "uipath-core"
-version = "0.5.8"
+version = "0.5.9"
 description = "UiPath Core abstractions"
 readme = { file = "README.md", content-type = "text/markdown" }
 requires-python = ">=3.11"

packages/uipath-core/src/uipath/core/guardrails/_evaluators.py

@@ -68,6 +68,26 @@ def _traverse(current: Any, remaining_parts: list[str]) -> None:
         field_name, array_depth = _parse_path_segment(part)
 
         if isinstance(current, dict):
+            if not field_name and array_depth != ArrayDepth.NONE:
+                # Path segment is purely array notation (e.g. [*]) with no
+                # field name.  This happens when the root data is a
+                # dict-wrapped array (e.g. {"output": [...]}) and the
+                # original path starts with [*].  Iterate over all list
+                # values in the dict so the array elements are reached.
+                for value in current.values():
+                    if isinstance(value, list):
+                        if array_depth == ArrayDepth.MATRIX:
+                            for row in value:
+                                if isinstance(row, list):
+                                    for item in row:
+                                        _traverse(item, next_parts)
+                                else:
+                                    _traverse(row, next_parts)
+                        else:  # SINGLE
+                            for item in value:
+                                _traverse(item, next_parts)
+                return
+
             if field_name not in current:
                 return
             next_value = current.get(field_name)

packages/uipath-core/tests/guardrails/test_deterministic_guardrails_service.py

@@ -1567,3 +1567,110 @@ def test_boolean_rule_missing_field_passes(
             guardrail=guardrail,
         )
         assert result.result == GuardrailValidationResultType.PASSED
+
+
+class TestWrappedArrayOutputEvaluation:
+    """Test that guardrails work when tool output is a dict-wrapped array.
+
+    When a tool returns a JSON array, _extract_tool_output_data wraps it as
+    {"output": [...]}.  Field paths starting with [*] (e.g. [*].author.email)
+    must still resolve correctly against the wrapped structure.
+    """
+
+    def test_word_rule_on_wrapped_array_output_detects_violation(
+        self, service: DeterministicGuardrailsService
+    ) -> None:
+        guardrail = DeterministicGuardrail(
+            id="test-wrapped-array",
+            name="Wrapped Array Guardrail",
+            description="Test wrapped array output",
+            enabled_for_evals=True,
+            guardrail_type="custom",
+            selector=GuardrailSelector(
+                scopes=[GuardrailScope.TOOL], match_names=["test"]
+            ),
+            rules=[
+                WordRule(
+                    rule_type="word",
+                    field_selector=SpecificFieldsSelector(
+                        selector_type="specific",
+                        fields=[
+                            FieldReference(
+                                path="[*].author.emailAddress",
+                                source=FieldSource.OUTPUT,
+                            )
+                        ],
+                    ),
+                    detects_violation=lambda s: "iana" in s,
+                    rule_description="email contains 'iana'",
+                ),
+            ],
+        )
+        # Simulates output from _extract_tool_output_data when tool returns an array.
+        # All emails contain "iana" so every field violates the rule → guardrail fails.
+        output_data = {
+            "output": [
+                {
+                    "author": {"emailAddress": "briana.smith@test.com"},
+                    "body": "comment1",
+                },
+                {
+                    "author": {"emailAddress": "adriana.jones@test.com"},
+                    "body": "comment2",
+                },
+            ]
+        }
+        result = service.evaluate_post_deterministic_guardrail(
+            input_data={},
+            output_data=output_data,
+            guardrail=guardrail,
+        )
+        assert result.result == GuardrailValidationResultType.VALIDATION_FAILED
+
+    def test_word_rule_on_wrapped_array_output_passes_when_no_match(
+        self, service: DeterministicGuardrailsService
+    ) -> None:
+        guardrail = DeterministicGuardrail(
+            id="test-wrapped-array",
+            name="Wrapped Array Guardrail",
+            description="Test wrapped array output",
+            enabled_for_evals=True,
+            guardrail_type="custom",
+            selector=GuardrailSelector(
+                scopes=[GuardrailScope.TOOL], match_names=["test"]
+            ),
+            rules=[
+                WordRule(
+                    rule_type="word",
+                    field_selector=SpecificFieldsSelector(
+                        selector_type="specific",
+                        fields=[
+                            FieldReference(
+                                path="[*].author.emailAddress",
+                                source=FieldSource.OUTPUT,
+                            )
+                        ],
+                    ),
+                    detects_violation=lambda s: "iana" in s,
+                    rule_description="email contains 'iana'",
+                ),
+            ],
+        )
+        output_data = {
+            "output": [
+                {
+                    "author": {"emailAddress": "mike.wilson@test.com"},
+                    "body": "comment1",
+                },
+                {
+                    "author": {"emailAddress": "sarah.clark@test.com"},
+                    "body": "comment2",
+                },
+            ]
+        }
+        result = service.evaluate_post_deterministic_guardrail(
+            input_data={},
+            output_data=output_data,
+            guardrail=guardrail,
+        )
+        assert result.result == GuardrailValidationResultType.PASSED