feat: port various nit changes from wip-v0.4 (#32506)

Lots of work that wasn't directly related to core
improvements/messages/testing functionality

Author: mdrxy

.github/workflows/api_doc_build.yml

@@ -52,7 +52,6 @@ jobs:
         run: |
           # Get unique repositories
           REPOS=$(echo "$REPOS_UNSORTED" | sort -u)
-
           # Checkout each unique repository
           for repo in $REPOS; do
             # Validate repository format (allow any org with proper format)
@@ -68,7 +67,6 @@ jobs:
               echo "Error: Invalid repository name: $REPO_NAME"
               exit 1
             fi
-
             echo "Checking out $repo to $REPO_NAME"
             git clone --depth 1 https://github.com/$repo.git $REPO_NAME
           done

.github/workflows/check_diffs.yml

@@ -30,6 +30,7 @@ jobs:
   build:
     name: 'Detect Changes & Set Matrix'
     runs-on: ubuntu-latest
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'ci-ignore') }}
     steps:
       - name: '📋 Checkout Code'
         uses: actions/checkout@v4

.github/workflows/codspeed.yml

@@ -20,6 +20,7 @@ jobs:
   codspeed:
     name: 'Benchmark'
     runs-on: ubuntu-latest
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'codspeed-ignore') }}
     strategy:
       matrix:
         include:

.vscode/settings.json

@@ -21,7 +21,7 @@
   "[python]": {
     "editor.formatOnSave": true,
     "editor.codeActionsOnSave": {
-      "source.organizeImports": "explicit",
+      "source.organizeImports.ruff": "explicit",
       "source.fixAll": "explicit"
     },
     "editor.defaultFormatter": "charliermarsh.ruff"
@@ -77,4 +77,6 @@
     "editor.tabSize": 2,
     "editor.insertSpaces": true
   },
+  "python.terminal.activateEnvironment": false,
+  "python.defaultInterpreterPath": "./.venv/bin/python"
 }

docs/api_reference/create_api_rst.py

@@ -97,7 +97,7 @@ def _load_module_members(module_path: str, namespace: str) -> ModuleMembers:
             if type(type_) is typing_extensions._TypedDictMeta:  # type: ignore
                 kind: ClassKind = "TypedDict"
             elif type(type_) is typing._TypedDictMeta:  # type: ignore
-                kind: ClassKind = "TypedDict"
+                kind = "TypedDict"
             elif (
                 issubclass(type_, Runnable)
                 and issubclass(type_, BaseModel)
@@ -189,7 +189,7 @@ def _load_package_modules(
         if isinstance(package_directory, str)
         else package_directory
     )
-    modules_by_namespace = {}
+    modules_by_namespace: Dict[str, ModuleMembers] = {}
 
     # Get the high level package name
     package_name = package_path.name
@@ -283,7 +283,7 @@ def _construct_doc(
 .. toctree::
     :hidden:
     :maxdepth: 2
-    
+
 """
     index_autosummary = """
 """
@@ -365,9 +365,9 @@ def _construct_doc(
 
                 module_doc += f"""\
     :template: {template}
-    
+
     {class_["qualified_name"]}
-    
+
 """
                 index_autosummary += f"""
     {class_["qualified_name"]}
@@ -550,8 +550,8 @@ def _build_index(dirs: List[str]) -> None:
     integrations = sorted(dir_ for dir_ in dirs if dir_ not in main_)
     doc = """# LangChain Python API Reference
 
-Welcome to the LangChain Python API reference. This is a reference for all 
-`langchain-x` packages. 
+Welcome to the LangChain Python API reference. This is a reference for all
+`langchain-x` packages.
 
 For user guides see [https://python.langchain.com](https://python.langchain.com).
 

docs/docs/contributing/how_to/testing.mdx

@@ -124,6 +124,47 @@ start "" htmlcov/index.html || open htmlcov/index.html
 
 ```
 
+## Snapshot Testing
+
+Some tests use [syrupy](https://github.com/tophat/syrupy) for snapshot testing, which captures the output of functions and compares them to stored snapshots. This is particularly useful for testing JSON schema generation and other structured outputs.
+
+### Updating Snapshots
+
+To update snapshots when the expected output has legitimately changed:
+
+```bash
+uv run --group test pytest path/to/test.py --snapshot-update
+```
+
+### Pydantic Version Compatibility Issues
+
+Pydantic generates different JSON schemas across versions, which can cause snapshot test failures in CI when tests run with different Pydantic versions than what was used to generate the snapshots.
+
+**Symptoms:**
+- CI fails with snapshot mismatches showing differences like missing or extra fields.
+- Tests pass locally but fail in CI with different Pydantic versions
+
+**Solution:**
+Locally update snapshots using the same Pydantic version that CI uses:
+
+1. **Identify the failing Pydantic version** from CI logs (e.g., `2.7.0`, `2.8.0`, `2.9.0`)
+
+2. **Update snapshots with that version:**
+   ```bash
+   uv run --with "pydantic==2.9.0" --group test pytest tests/unit_tests/path/to/test.py::test_name --snapshot-update
+   ```
+
+3. **Verify compatibility across supported versions:**
+   ```bash
+   # Test with the version you used to update
+   uv run --with "pydantic==2.9.0" --group test pytest tests/unit_tests/path/to/test.py::test_name
+
+   # Test with other supported versions
+   uv run --with "pydantic==2.8.0" --group test pytest tests/unit_tests/path/to/test.py::test_name
+   ```
+
+**Note:** Some tests use `@pytest.mark.skipif` decorators to only run with specific Pydantic version ranges (e.g., `PYDANTIC_VERSION_AT_LEAST_210`). Make sure to understand these constraints when updating snapshots.
+
 ## Coverage
 
 Code coverage (i.e. the amount of code that is covered by unit tests) helps identify areas of the code that are potentially more or less brittle.

libs/core/langchain_core/_api/beta_decorator.py

@@ -144,7 +144,7 @@ def warn_if_direct_instance(
                 obj.__init__ = functools.wraps(obj.__init__)(  # type: ignore[misc]
                     warn_if_direct_instance
                 )
-                return cast("T", obj)
+                return obj
 
         elif isinstance(obj, property):
             if not _obj_type:

libs/core/langchain_core/_api/deprecation.py

@@ -225,7 +225,7 @@ def warn_if_direct_instance(
                 obj.__init__ = functools.wraps(obj.__init__)(  # type: ignore[misc]
                     warn_if_direct_instance
                 )
-                return cast("T", obj)
+                return obj
 
         elif isinstance(obj, FieldInfoV1):
             wrapped = None

libs/core/langchain_core/messages/modifier.py

@@ -13,7 +13,7 @@ class RemoveMessage(BaseMessage):
 
     def __init__(
         self,
-        id: str,  # noqa: A002
+        id: str,
         **kwargs: Any,
     ) -> None:
         """Create a RemoveMessage.

libs/core/langchain_core/messages/tool.py

@@ -212,7 +212,7 @@ def tool_call(
     *,
     name: str,
     args: dict[str, Any],
-    id: Optional[str],  # noqa: A002
+    id: Optional[str],
 ) -> ToolCall:
     """Create a tool call.
 
@@ -260,7 +260,7 @@ def tool_call_chunk(
     *,
     name: Optional[str] = None,
     args: Optional[str] = None,
-    id: Optional[str] = None,  # noqa: A002
+    id: Optional[str] = None,
     index: Optional[int] = None,
 ) -> ToolCallChunk:
     """Create a tool call chunk.
@@ -298,7 +298,7 @@ def invalid_tool_call(
     *,
     name: Optional[str] = None,
     args: Optional[str] = None,
-    id: Optional[str] = None,  # noqa: A002
+    id: Optional[str] = None,
     error: Optional[str] = None,
 ) -> InvalidToolCall:
     """Create an invalid tool call.