From fd5a998e2af681ccfdc952b32f2ac3361e109bdb Mon Sep 17 00:00:00 2001
From: spicy-sauce <yshirizli@gmail.com>
Date: Sun, 5 Jan 2025 14:05:24 +0200
Subject: [PATCH] map_record() handling of None in nested paths

---
 core/src/datayoga_core/write_utils.py | 13 +++++-
 core/tests/test_write_utils.py        | 67 +++++++++++++++++++++++++++
 2 files changed, 78 insertions(+), 2 deletions(-)

diff --git a/core/src/datayoga_core/write_utils.py b/core/src/datayoga_core/write_utils.py
index 341724d0..c8d7f3b8 100644
--- a/core/src/datayoga_core/write_utils.py
+++ b/core/src/datayoga_core/write_utils.py
@@ -58,11 +58,20 @@ def map_record(
 
         source_path = utils.split_field(source)
         obj = record
+        found = True
         for key in source_path:
             key = utils.unescape_field(key)
-            if key in obj:
+
+            if obj is None:
+                found = False
+                break
+
+            if isinstance(obj, dict) and key in obj:
                 obj = obj[key]
+            else:
+                found = False
+                break
 
-        mapped_record[target] = obj if obj != record else None
+        mapped_record[target] = obj if found else None
 
     return mapped_record
diff --git a/core/tests/test_write_utils.py b/core/tests/test_write_utils.py
index d7e7a664..00911aac 100644
--- a/core/tests/test_write_utils.py
+++ b/core/tests/test_write_utils.py
@@ -1,3 +1,4 @@
+import pytest
 from datayoga_core import write_utils
 from datayoga_core.result import Status
 
@@ -32,3 +33,69 @@ def test_group_by_opcode_invalid_opcode():
     groups = write_utils.group_records_by_opcode(change_records, opcode_field="opcode")
     assert groups["r"] == change_records[0:1]
     assert groups["x"] == change_records[1:2]
+
+
+@pytest.mark.parametrize("record, source, expected", [
+    # Existing simple nested key
+    (
+        {"value": {"id": 123}},
+        "value.id",
+        {"target": 123}
+    ),
+    # Existing deeply nested key
+    (
+        {"user": {"profile": {"email": "john@example.com"}}},
+        "user.profile.email",
+        {"target": "john@example.com"}
+    ),
+    # Missing simple nested key
+    (
+        {"value": {"x": 2}},
+        "value.id",
+        {"target": None}
+    ),
+    # Missing deeply nested key
+    (
+        {"user": {"profile": {"name": "John"}}},
+        "user.profile.email",
+        {"target": None}
+    ),
+    # Partially nested key
+    (
+        {"user": {"profile": {"name": "John"}}},
+        "user.address.street",
+        {"target": None}
+    ),
+    # Mixed case with existing and non-existing keys
+    (
+        {"data": {"info": {"id": 123, "active": True}}},
+        "data.info.status",
+        {"target": None}
+    ),
+    # Empty nested structure
+    (
+        {"user": {}},
+        "user.profile",
+        {"target": None}
+    ),
+    # Null value in nested structure
+    (
+        {"user": {"profile": None}},
+        "user.profile.name",
+        {"target": None}
+    ),
+    # Boolean value
+    (
+        {"settings": {"active": True}},
+        "settings.active",
+        {"target": True}
+    )
+])
+def test_map_record_nested_key(record, source, expected):
+    """Tests map_record function's handling of nested keys, including existing and missing scenarios."""
+    mapped = write_utils.map_record(
+        record,
+        keys=[{"target": source}]
+    )
+
+    assert mapped == expected, f"Failed for record {record} with source {source}"