Add structure hook for Union[str, List[InlayHintLabelPart]] (#219)

Fixes #218

.github/workflows/pr-check.yml

@@ -86,6 +86,10 @@ jobs:
         run: python -m pip install -r ./packages/python/requirements.txt
         shell: bash
 
+      - name: Install pygls
+        run: python -m pip install --no-deps ./smoke_tests
+        shell: bash
+
       - name: Pip List
         run: python -m pip list
         shell: bash

packages/python/lsprotocol/_hooks.py

@@ -383,6 +383,16 @@ def _inlay_hint_provider_hook(
         else:
             return converter.structure(object_, lsp_types.InlayHintOptions)
 
+    def _inlay_hint_label_part_hook(
+        object_: Any, _: type
+    ) -> Union[str, List[lsp_types.InlayHintLabelPart]]:
+        if isinstance(object_, str):
+            return object_
+
+        return [
+            converter.structure(item, lsp_types.InlayHintLabelPart) for item in object_
+        ]
+
     def _diagnostic_provider_hook(
         object_: Any, _: type
     ) -> Union[
@@ -775,6 +785,10 @@ def _watch_kind_hook(
             ],
             _inlay_hint_provider_hook,
         ),
+        (
+            Union[str, List[lsp_types.InlayHintLabelPart]],
+            _inlay_hint_label_part_hook,
+        ),
         (
             Optional[
                 Union[

tests/python/requests/test_inlay_hint_resolve_request.py

@@ -0,0 +1,86 @@
+# Copyright (c) Microsoft Corporation. All rights reserved.
+# Licensed under the MIT License.
+
+import json
+import uuid
+
+import hamcrest
+import jsonrpc
+import pytest
+from cattrs.errors import ClassValidationError
+
+ID = str(uuid.uuid4())
+
+TEST_DATA = [
+    (
+        {
+            "id": ID,
+            "method": "inlayHint/resolve",
+            "params": {
+                "position": {"line": 6, "character": 5},
+                "label": "a label",
+                "kind": 1,
+                "paddingLeft": False,
+                "paddingRight": True,
+            },
+            "jsonrpc": "2.0",
+        },
+        json.dumps(
+            {
+                "id": ID,
+                "params": {
+                    "position": {"line": 6, "character": 5},
+                    "label": "a label",
+                    "kind": 1,
+                    "paddingLeft": False,
+                    "paddingRight": True,
+                },
+                "method": "inlayHint/resolve",
+                "jsonrpc": "2.0",
+            }
+        ),
+    ),
+    (
+        {
+            "id": ID,
+            "method": "inlayHint/resolve",
+            "params": {
+                "position": {"line": 6, "character": 5},
+                "label": [
+                    {"value": "part 1"},
+                    {"value": "part 2", "tooltip": "a tooltip"},
+                ],
+                "kind": 1,
+                "paddingLeft": False,
+                "paddingRight": True,
+            },
+            "jsonrpc": "2.0",
+        },
+        json.dumps(
+            {
+                "id": ID,
+                "params": {
+                    "position": {"line": 6, "character": 5},
+                    "label": [
+                        {"value": "part 1"},
+                        {"value": "part 2", "tooltip": "a tooltip"},
+                    ],
+                    "kind": 1,
+                    "paddingLeft": False,
+                    "paddingRight": True,
+                },
+                "method": "inlayHint/resolve",
+                "jsonrpc": "2.0",
+            }
+        ),
+    ),
+]
+
+
+@pytest.mark.parametrize("index", list(range(0, len(TEST_DATA))))
+def test_inlay_hint_resolve_request_serialization(index):
+    data, expected = TEST_DATA[index]
+    data_str = json.dumps(data)
+    parsed = jsonrpc.from_json(data_str)
+    actual_str = jsonrpc.to_json(parsed)
+    hamcrest.assert_that(actual_str, hamcrest.is_(expected))