fix(langchain_v1): removed unsed functions in tool_call_limit middleware (#33735)

These functions seem unused and can be removed.

Author: christian-bromann

libs/langchain_v1/langchain/agents/middleware/tool_call_limit.py

@@ -4,7 +4,7 @@
 
 from typing import TYPE_CHECKING, Annotated, Any, Literal
 
-from langchain_core.messages import AIMessage, AnyMessage, HumanMessage
+from langchain_core.messages import AIMessage
 from langgraph.channels.untracked_value import UntrackedValue
 from typing_extensions import NotRequired
 
@@ -33,53 +33,6 @@ class ToolCallLimitState(AgentState):
     run_tool_call_count: NotRequired[Annotated[dict[str, int], UntrackedValue, PrivateStateAttr]]
 
 
-def _count_tool_calls_in_messages(messages: list[AnyMessage], tool_name: str | None = None) -> int:
-    """Count tool calls in a list of messages.
-
-    Args:
-        messages: List of messages to count tool calls in.
-        tool_name: If specified, only count calls to this specific tool.
-            If `None`, count all tool calls.
-
-    Returns:
-        The total number of tool calls (optionally filtered by tool_name).
-    """
-    count = 0
-    for message in messages:
-        if isinstance(message, AIMessage) and message.tool_calls:
-            if tool_name is None:
-                # Count all tool calls
-                count += len(message.tool_calls)
-            else:
-                # Count only calls to the specified tool
-                count += sum(1 for tc in message.tool_calls if tc["name"] == tool_name)
-    return count
-
-
-def _get_run_messages(messages: list[AnyMessage]) -> list[AnyMessage]:
-    """Get messages from the current run (after the last HumanMessage).
-
-    Args:
-        messages: Full list of messages.
-
-    Returns:
-        Messages from the current run (after last HumanMessage).
-    """
-    # Find the last HumanMessage
-    last_human_index = -1
-    for i in range(len(messages) - 1, -1, -1):
-        if isinstance(messages[i], HumanMessage):
-            last_human_index = i
-            break
-
-    # If no HumanMessage found, return all messages
-    if last_human_index == -1:
-        return messages
-
-    # Return messages after the last HumanMessage
-    return messages[last_human_index + 1 :]
-
-
 def _build_tool_limit_exceeded_message(
     thread_count: int,
     run_count: int,

libs/langchain_v1/tests/unit_tests/agents/test_tool_call_limit.py

@@ -9,88 +9,10 @@
 from langchain.agents.middleware.tool_call_limit import (
     ToolCallLimitExceededError,
     ToolCallLimitMiddleware,
-    _count_tool_calls_in_messages,
-    _get_run_messages,
 )
 from tests.unit_tests.agents.test_middleware_agent import FakeToolCallingModel
 
 
-def test_count_tool_calls_in_messages():
-    """Test counting tool calls in messages."""
-    # Test with no messages
-    assert _count_tool_calls_in_messages([]) == 0
-
-    # Test with messages but no tool calls
-    messages = [
-        HumanMessage("Hello"),
-        AIMessage("Hi there"),
-    ]
-    assert _count_tool_calls_in_messages(messages) == 0
-
-    # Test with tool calls
-    messages = [
-        HumanMessage("Search for something"),
-        AIMessage(
-            "Searching...",
-            tool_calls=[
-                {"name": "search", "args": {"query": "test"}, "id": "1"},
-                {"name": "calculator", "args": {"expression": "1+1"}, "id": "2"},
-            ],
-        ),
-        ToolMessage("Result 1", tool_call_id="1"),
-        ToolMessage("Result 2", tool_call_id="2"),
-        AIMessage(
-            "More searching...",
-            tool_calls=[
-                {"name": "search", "args": {"query": "another"}, "id": "3"},
-            ],
-        ),
-    ]
-    # Total: 3 tool calls (2 from first AI message, 1 from second)
-    assert _count_tool_calls_in_messages(messages) == 3
-
-    # Test filtering by tool name
-    assert _count_tool_calls_in_messages(messages, tool_name="search") == 2
-    assert _count_tool_calls_in_messages(messages, tool_name="calculator") == 1
-    assert _count_tool_calls_in_messages(messages, tool_name="nonexistent") == 0
-
-
-def test_get_run_messages():
-    """Test extracting run messages after last HumanMessage."""
-    # Test with no messages
-    assert _get_run_messages([]) == []
-
-    # Test with no HumanMessage
-    messages = [
-        AIMessage("Hello"),
-        AIMessage("World"),
-    ]
-    assert _get_run_messages(messages) == messages
-
-    # Test with HumanMessage at the end
-    messages = [
-        AIMessage("Previous"),
-        HumanMessage("New question"),
-    ]
-    assert _get_run_messages(messages) == []
-
-    # Test with messages after HumanMessage
-    messages = [
-        AIMessage("Previous"),
-        ToolMessage("Previous result", tool_call_id="0"),
-        HumanMessage("New question"),
-        AIMessage(
-            "Response",
-            tool_calls=[{"name": "search", "args": {}, "id": "1"}],
-        ),
-        ToolMessage("Result", tool_call_id="1"),
-    ]
-    run_messages = _get_run_messages(messages)
-    assert len(run_messages) == 2
-    assert isinstance(run_messages[0], AIMessage)
-    assert isinstance(run_messages[1], ToolMessage)
-
-
 def test_middleware_initialization_validation():
     """Test that middleware initialization validates parameters correctly."""
     # Test that at least one limit must be specified