Resolve symlinks before validating file extensions in the deprecated
`save()` method on prompt classes.
Credit to Jeff Ponte (@JDP-Security) for reporting the symlink
resolution issue.
## Summary
- The inline comment at `langchain_core/prompts/string.py:67-69`
incorrectly states that `SandboxedEnvironment` "blocks ALL
attribute/method access" and that "only simple variable lookups like
`{{variable}}` are allowed."
- In reality, Jinja2's `SandboxedEnvironment` only blocks access to
dunder attributes (`__class__`, `__globals__`, etc.) to prevent sandbox
escapes. Regular attribute access like `{{obj.content}}` and method
calls remain allowed.
- This misleading comment was left behind when a
`_RestrictedSandboxedEnvironment` class was reverted in commit
395c8d0bd4. Updated to accurately describe the actual behavior.
## Why this matters
The comment could mislead developers into trusting partially-untrusted
templates, believing attribute access is blocked when it is not. The
function's docstring already correctly warns against untrusted
templates.
## Test plan
- [ ] No behavioral change — comment-only fix
- [ ] Verified `SandboxedEnvironment` behavior matches updated comment
> This PR was authored with the help of AI tools.
it looks scary but i promise it is not
improving documentation consistency across core. primarily update
docstrings and comments for better formatting, readability, and
accuracy, as well as add minor clarifications and formatting
improvements to user-facing documentation.
### Description
`ChatPromptTemplate.from_messages` supports multiple tuple formats for
defining message templates. One documented format is `(message class,
template)`, which allows users to specify the message type using the
class directly:
```python
ChatPromptTemplate.from_messages([
(SystemMessage, "You are a helpful assistant named {name}."),
(HumanMessage, "{input}"),
])
```
However, this syntax was broken. Passing a tuple like `(HumanMessage,
"{input}")` would raise a Pydantic validation error because the
conversion logic in `_convert_to_message_template` didn't handle
`BaseMessage` subclasses—it only recognized string-based role
identifiers like `"human"` or `"system"`.
This PR adds the missing branch to detect when the first element of a
tuple is a message class (by checking for the `type` class attribute)
and routes it through `_create_template_from_message_type`, which
already knows how to create the appropriate `MessagePromptTemplate` for
each message type.
### Changes
- Updated `_convert_to_message_template` to properly support `(message
class, template)` tuples
### Testing
Added 16 comprehensive unit tests covering:
- Basic usage with `HumanMessage`, `AIMessage`, and `SystemMessage`
classes
- Integration with `invoke()` method
- Mixed syntax (message class tuples alongside string tuples)
- Multiple template variables
- Edge cases: empty templates, static text (no variables)
- Correct extraction of `input_variables`
- Partial variables support
- Combination with `MessagesPlaceholder`
- Mustache template format
- Template operations: `append()`, `extend()`, concatenation, and
slicing
- Special characters and unicode in templates
### Issue
Fixes#33791
### Dependencies
None
---------
Co-authored-by: Mason Daugherty <mason@langchain.dev>
* FIxed where possible
* Used `cast` when not possible to fix
---------
Co-authored-by: Mason Daugherty <github@mdrxy.com>
Co-authored-by: Mason Daugherty <mason@langchain.dev>
* Fixed a few TC
* Added a few Pydantic classes to
`flake8-type-checking.runtime-evaluated-base-classes` (not as much as I
would have imagined)
* Added a few `noqa: TC`
* Activated TC rules
- **Description:** if you dont pass in schema= or schema_= to
StrucutredPrompt(...) today you get a confusing KeyError. Raise a more
readable ValueError instead.
- **Issue:** na
- **Dependencies:** na
Largely:
- Remove explicit `"Default is x"` since new refs show default inferred
from sig
- Inline code (useful for eventual parsing)
- Fix code block rendering (indentations)
**Description:**
currently `mustache_schema("{{x.y}} {{x}}")` will error. pr fixes
**Issue:** na
**Dependencies:**na
---------
Co-authored-by: Bagatur <baskaryan@gmail.com>
Removed:
- `libs/core/langchain_core/chat_history.py`: `add_user_message` and
`add_ai_message` in favor of `add_messages` and `aadd_messages`
- `libs/core/langchain_core/language_models/base.py`: `predict`,
`predict_messages`, and async versions in favor of `invoke`. removed
`_all_required_field_names` since it was a wrapper on
`get_pydantic_field_names`
- `libs/core/langchain_core/language_models/chat_models.py`:
`callback_manager` param in favor of `callbacks`. `__call__` and
`call_as_llm` method in favor of `invoke`
- `libs/core/langchain_core/language_models/llms.py`: `callback_manager`
param in favor of `callbacks`. `__call__`, `predict`, `apredict`, and
`apredict_messages` methods in favor of `invoke`
- `libs/core/langchain_core/prompts/chat.py`: `from_role_strings` and
`from_strings` in favor of `from_messages`
- `libs/core/langchain_core/prompts/pipeline.py`: removed
`PipelinePromptTemplate`
- `libs/core/langchain_core/prompts/prompt.py`: `input_variables` param
on `from_file` as it wasn't used
- `libs/core/langchain_core/tools/base.py`: `callback_manager` param in
favor of `callbacks`
- `libs/core/langchain_core/tracers/context.py`: `tracing_enabled` in
favor of `tracing_enabled_v2`
- `libs/core/langchain_core/tracers/langchain_v1.py`: entire module
- `libs/core/langchain_core/utils/loading.py`: entire module,
`try_load_from_hub`
- `libs/core/langchain_core/vectorstores/in_memory.py`: `upsert` in
favor of `add_documents`
- `libs/standard-tests/langchain_tests/integration_tests/chat_models.py`
and `libs/standard-tests/langchain_tests/unit_tests/chat_models.py`:
`tool_choice_value` as models should accept `tool_choice="any"`
- `langchain` will consequently no longer expose these items if it was
previously
---------
Co-authored-by: Mohammad Mohtashim <45242107+keenborder786@users.noreply.github.com>
Co-authored-by: Caspar Broekhuizen <caspar@langchain.dev>
Co-authored-by: ccurme <chester.curme@gmail.com>
Co-authored-by: Christophe Bornet <cbornet@hotmail.com>
Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>
Co-authored-by: Sadra Barikbin <sadraqazvin1@yahoo.com>
Co-authored-by: Vadym Barda <vadim.barda@gmail.com>
Ensures proper reStructuredText formatting by adding the required blank
line before closing docstring quotes, which resolves the "Block quote
ends without a blank line; unexpected unindent" warning.
**PR title**:
add deprecation notice for PipelinePromptTemplate
**PR message**:
In the API documentation, PipelinePromptTemplate is marked as
deprecated, but this is not mentioned in the docs.
I'm submitting this PR to add a deprecation notice to the docs.
**Tests**:
N/A (documentation only)
---------
Co-authored-by: Mason Daugherty <github@mdrxy.com>
This PR changes the return type hints of the `format_prompt` and
`aformat_prompt` methods in `BaseChatPromptTemplate` from `PromptValue`
to `ChatPromptValue`. Since both methods always return a
`ChatPromptValue`.