From 196a1b161d92813bf79e76caba6713c232617386 Mon Sep 17 00:00:00 2001
From: Puneet Dixit <rvit23bcs086.rvitm@rvei.edu.in>
Date: Thu, 21 May 2026 14:19:48 +0530
Subject: [PATCH] Fix DataTable conditional style typing

---
 components/dash-table/dash_prop_typing.py     | 27 ++++++++
 .../development/test_dash_table_typing.py     | 64 +++++++++++++++++++
 2 files changed, 91 insertions(+)
 create mode 100644 components/dash-table/dash_prop_typing.py
 create mode 100644 tests/unit/development/test_dash_table_typing.py

diff --git a/components/dash-table/dash_prop_typing.py b/components/dash-table/dash_prop_typing.py
new file mode 100644
index 0000000000..22fa7fd2a5
--- /dev/null
+++ b/components/dash-table/dash_prop_typing.py
@@ -0,0 +1,27 @@
+# This file is automatically loaded on build time to generate types.
+
+from dash.development._py_prop_typing import get_prop_typing
+
+
+def generate_conditional_style(type_info, component_name, prop_name):
+    condition_type = get_prop_typing(
+        type_info["value"]["name"],
+        component_name,
+        prop_name,
+        type_info["value"],
+    )
+    return (
+        "typing.Sequence["
+        f"typing.Union[{condition_type}, typing.Dict[str, typing.Any]]"
+        "]"
+    )
+
+
+custom_props = {
+    "DataTable": {
+        "style_cell_conditional": generate_conditional_style,
+        "style_data_conditional": generate_conditional_style,
+        "style_filter_conditional": generate_conditional_style,
+        "style_header_conditional": generate_conditional_style,
+    },
+}
diff --git a/tests/unit/development/test_dash_table_typing.py b/tests/unit/development/test_dash_table_typing.py
new file mode 100644
index 0000000000..77383f1091
--- /dev/null
+++ b/tests/unit/development/test_dash_table_typing.py
@@ -0,0 +1,64 @@
+import sys
+from pathlib import Path
+
+import pytest
+
+from dash.development._py_components_generation import generate_class_string
+from dash.development._py_prop_typing import shapes
+
+CONDITIONAL_STYLE_TYPE = {
+    "name": "arrayOf",
+    "value": {
+        "name": "shape",
+        "value": {
+            "if": {
+                "name": "exact",
+                "value": {
+                    "column_id": {"name": "string", "required": False},
+                },
+                "required": False,
+            },
+        },
+    },
+}
+
+
+@pytest.mark.parametrize(
+    "prop_name, shape_name",
+    [
+        ("style_cell_conditional", "StyleCellConditional"),
+        ("style_data_conditional", "StyleDataConditional"),
+        ("style_filter_conditional", "StyleFilterConditional"),
+        ("style_header_conditional", "StyleHeaderConditional"),
+    ],
+)
+def test_datatable_conditional_styles_allow_style_keys(
+    monkeypatch, prop_name, shape_name
+):
+    dash_table_dir = Path(__file__).resolve().parents[3] / "components" / "dash-table"
+    monkeypatch.syspath_prepend(str(dash_table_dir))
+    sys.modules.pop("dash_prop_typing", None)
+    shapes.clear()
+
+    generated = generate_class_string(
+        typename="DataTable",
+        props={
+            prop_name: {
+                "type": CONDITIONAL_STYLE_TYPE,
+                "required": False,
+                "description": "Conditional style",
+            },
+        },
+        description="DataTable",
+        namespace="dash_table",
+        custom_typing_module="dash_prop_typing",
+    )
+
+    assert (
+        f'{prop_name}: typing.Optional[typing.Sequence[typing.Union["{shape_name}", '
+        "typing.Dict[str, typing.Any]]]] = None"
+    ) in generated
+    assert f'"if": NotRequired["{shape_name}If"]' in generated
+
+    shapes.clear()
+    sys.modules.pop("dash_prop_typing", None)