Add order of list source reference validation (#243)

app/error_messages.py

@@ -40,3 +40,4 @@
     "Variants have more than one question type for block."
 )
 PREVIEW_WITHOUT_INTRODUCTION_BLOCK = "No introduction block found. Introduction block is mandatory when using the preview questions feature."
+LIST_REFERENCED_BEFORE_CREATED = "List referenced as source before it has been created."

app/validators/questionnaire_schema.py

@@ -152,6 +152,7 @@ def __init__(self, schema):
             for block in list_collector.get("repeating_blocks", [])
         }
         self._answers_with_context = {}
+        self._lists_with_context = {}
 
     @lru_cache
     def get_block_ids_for_block_type(self, block_type: str) -> list[str]:
@@ -209,6 +210,41 @@ def answers_with_context(self):
         self._answers_with_context = answers_dict
         return self._answers_with_context
 
+    @property
+    def lists_with_context(self):
+        if supplementary_list := self.supplementary_lists:
+            for list_id in supplementary_list:
+                self._lists_with_context[list_id] = {
+                    "section_index": 0,
+                    "block_index": 0,
+                }
+
+        if blocks := self.list_collectors:
+            for block in blocks:
+                list_id = block["for_list"]
+                if list_id not in self._lists_with_context:
+                    section_id = self.get_section_id_for_block_id(block["id"])
+                    section_index = self.section_ids.index(section_id)
+                    self._lists_with_context[list_id] = {
+                        "section_index": section_index,
+                        "block_index": self.block_ids.index(block["id"]),
+                    }
+        if blocks := self.get_blocks(type="PrimaryPersonListCollector"):
+            for block in blocks:
+                list_id = block["for_list"]
+                if list_id not in self._lists_with_context or (
+                    self.block_ids.index(block["id"])
+                    < self._lists_with_context[list_id]["block_index"]
+                ):
+                    section_id = self.get_section_id_for_block_id(block["id"])
+                    section_index = self.section_ids.index(section_id)
+                    self._lists_with_context[list_id] = {
+                        "section_index": section_index,
+                        "block_index": self.block_ids.index(block["id"]),
+                    }
+
+        return self._lists_with_context
+
     @staticmethod
     def capture_answers(*, answers, answers_dict, context):
         for answer in answers:

app/validators/questionnaire_validator.py

@@ -6,7 +6,11 @@
 from app.validators.answer_code_validator import AnswerCodeValidator
 from app.validators.metadata_validator import MetadataValidator
 from app.validators.placeholders.placeholder_validator import PlaceholderValidator
-from app.validators.questionnaire_schema import QuestionnaireSchema, find_duplicates
+from app.validators.questionnaire_schema import (
+    QuestionnaireSchema,
+    find_duplicates,
+    get_object_containing_key,
+)
 from app.validators.sections.section_validator import SectionValidator
 from app.validators.validator import Validator
 
@@ -30,6 +34,7 @@ def validate(self):
         self.validate_duplicates()
         self.validate_smart_quotes()
         self.validate_white_spaces()
+        self.validate_list_references()
 
         for section in self.questionnaire_schema.sections:
             section_validator = SectionValidator(section, self.questionnaire_schema)
@@ -134,3 +139,37 @@ def validate_introduction_block(self):
         )
         if not has_introduction_blocks:
             self.add_error(error_messages.PREVIEW_WITHOUT_INTRODUCTION_BLOCK)
+
+    def validate_list_references(self):
+        lists_with_context = self.questionnaire_schema.lists_with_context
+
+        # We need to keep track of section index for: common_definitions.json#/section_enabled
+        for section_index, section in enumerate(self.questionnaire_schema.sections):
+            identifier_references = get_object_containing_key(section, "source")
+            for _, identifier_reference, parent_block in identifier_references:
+                if identifier_reference["source"] == "list":
+                    list_identifier = identifier_reference["identifier"]
+                    if parent_block:
+                        if (
+                            self.questionnaire_schema.block_ids.index(
+                                parent_block["id"]
+                            )
+                            < lists_with_context[list_identifier]["block_index"]
+                        ):
+                            self.add_error(
+                                error_messages.LIST_REFERENCED_BEFORE_CREATED.format(),
+                                list_id=list_identifier,
+                                section_id=section["id"],
+                                block_id=parent_block["id"],
+                            )
+                    elif (
+                        section_index
+                        < lists_with_context[list_identifier]["section_index"]
+                    ):
+                        # Section level "enabled" rule that can use list source,
+                        # check: common_definitions.json#/section_enabled
+                        self.add_error(
+                            error_messages.LIST_REFERENCED_BEFORE_CREATED.format(),
+                            list_name=list_identifier,
+                            section_id=section["id"],
+                        )