From aeea33c768a8b0cce0cd15c4d2d3dd77d1b6f0a7 Mon Sep 17 00:00:00 2001
From: Andreas Motl <andreas.motl@crate.io>
Date: Sun, 22 Sep 2024 10:06:02 +0200
Subject: [PATCH] Zyp/Tests: Improve test cases for `to_object`

---
 tests/zyp/moksha/test_jq.py | 68 ++++++++++++++++++++++++++++++++++---
 1 file changed, 64 insertions(+), 4 deletions(-)

diff --git a/tests/zyp/moksha/test_jq.py b/tests/zyp/moksha/test_jq.py
index bd48681..e723efd 100644
--- a/tests/zyp/moksha/test_jq.py
+++ b/tests/zyp/moksha/test_jq.py
@@ -163,18 +163,78 @@ def test_moksha_jq_cast_array_iterable():
     assert transformation.apply(data_in) == data_out
 
 
-def test_moksha_jq_cast_object():
+def test_moksha_jq_cast_object_naive():
     """
-    Verify type casting using moksha/jq.
+    Lists are hard. Verify type casting using jqlang stdlib's `to_object` on array of objects.
+
+    The naive approach will manifest substructures even on documents
+    that don't include the relevant attribute at all.
     """
 
-    data_in = [{"data": [{"abc": 123}, {"abc": 456}, {"abc": {"id": 789}}]}]
-    data_out = [{"data": [{"abc": {"id": 123}}, {"abc": {"id": 456}}, {"abc": {"id": 789}}]}]
+    data_in = [
+        {
+            "data": [
+                {"abc": 123},
+                {"abc": 456},
+                {"abc": {"id": 789}},
+                {},
+                {"def": 999},
+            ]
+        },
+    ]
+    data_out = [
+        {
+            "data": [
+                {"abc": {"id": 123}},
+                {"abc": {"id": 456}},
+                {"abc": {"id": 789}},
+                {"abc": {"id": None}},
+                {"abc": {"id": None}, "def": 999},
+            ]
+        },
+    ]
 
     transformation = MokshaTransformation().jq('.[] |= (.data[].abc |= to_object({"key": "id"}))')
     assert transformation.apply(data_in) == data_out
 
 
+def test_moksha_jq_cast_object_advanced():
+    """
+    Lists are hard. Verify type casting using jqlang stdlib's `to_object` on array of objects.
+
+    The advanced approach will manifest substructures only on documents
+    that include the relevant attribute.
+    """
+
+    data_in = [
+        {
+            "data": [
+                {"abc": 123},
+                {"abc": 456},
+                {"abc": {"id": 789}},
+                {},
+                {"def": 999},
+            ]
+        },
+    ]
+    data_out = [
+        {
+            "data": [
+                {"abc": {"id": 123}},
+                {"abc": {"id": 456}},
+                {"abc": {"id": 789}},
+                {},
+                {"def": 999},
+            ]
+        },
+    ]
+
+    transformation = MokshaTransformation().jq(
+        '.[] |= (.data[] |= (if .abc then .abc |= to_object({"key": "id"}) end))'
+    )
+    assert transformation.apply(data_in) == data_out
+
+
 def test_moksha_jq_prune_array_of_objects():
     """
     Verify dropping arrays of objects recursively.