fix: type checker errors in flow modules

Co-Authored-By: Joe Moura <joao@crewai.com>

src/crewai/flow/core_flow_utils.py

@@ -17,7 +17,7 @@ from typing import Any, Callable, Dict, List, Optional, Set, Union
 from pydantic import BaseModel
 
 
-def get_possible_return_constants(function: callable) -> Optional[List[str]]:
+def get_possible_return_constants(function: Callable[..., Any]) -> Optional[List[str]]:
     """Extract possible string return values from a function by analyzing its source code.
     
     Analyzes the function's source code using AST to identify string constants that

src/crewai/flow/flow_visual_utils.py

@@ -5,13 +5,13 @@ Flow graphs and calculating layout information. These utilities are separated
 from general-purpose utilities to maintain a clean dependency structure.
 """
 
-from typing import TYPE_CHECKING, Dict, List, Set
+from typing import TYPE_CHECKING, Dict, List, Set, Any
 
 if TYPE_CHECKING:
     from crewai.flow.flow import Flow
 
 
-def calculate_node_levels(flow: Flow) -> Dict[str, int]:
+def calculate_node_levels(flow: Flow[Any]) -> Dict[str, int]:
     """Calculate the hierarchical level of each node in the flow graph.
     
     Uses breadth-first traversal to assign levels to nodes, starting with
@@ -35,10 +35,10 @@ def calculate_node_levels(flow: Flow) -> Dict[str, int]:
         >>> calculate_node_levels(flow)
         {'start': 0, 'second': 1}
     """
-    levels = {}
-    queue = []
-    visited = set()
-    pending_and_listeners = {}
+    levels: Dict[str, int] = {}
+    queue: List[str] = []
+    visited: Set[str] = set()
+    pending_and_listeners: Dict[str, Set[str]] = {}
 
     # Make all start methods at level 0
     for method_name, method in flow._methods.items():
@@ -97,7 +97,7 @@ def calculate_node_levels(flow: Flow) -> Dict[str, int]:
     return levels
 
 
-def count_outgoing_edges(flow: Flow) -> Dict[str, int]:
+def count_outgoing_edges(flow: Flow[Any]) -> Dict[str, int]:
     """Count the number of outgoing edges for each node in the flow graph.
     
     An outgoing edge represents a connection from a method to a listener
@@ -111,7 +111,7 @@ def count_outgoing_edges(flow: Flow) -> Dict[str, int]:
         dict[str, int]: Dictionary mapping method names to their number
             of outgoing connections
     """
-    counts = {}
+    counts: Dict[str, int] = {}
     for method_name in flow._methods:
         counts[method_name] = 0
     for method_name in flow._listeners:
@@ -122,7 +122,7 @@ def count_outgoing_edges(flow: Flow) -> Dict[str, int]:
     return counts
 
 
-def build_ancestor_dict(flow: Flow) -> Dict[str, Set[str]]:
+def build_ancestor_dict(flow: Flow[Any]) -> Dict[str, Set[str]]:
     """Build a dictionary mapping each node to its set of ancestor nodes.
     
     Uses depth-first search to identify all ancestors (direct and indirect
@@ -147,7 +147,7 @@ def build_ancestor_dict(flow: Flow) -> Dict[str, Set[str]]:
 
 
 def dfs_ancestors(node: str, ancestors: Dict[str, Set[str]], 
-                visited: Set[str], flow: Flow) -> None:
+                visited: Set[str], flow: Flow[Any]) -> None:
     """Perform depth-first search to populate the ancestors dictionary.
     
     Helper function for build_ancestor_dict that recursively traverses
@@ -182,7 +182,7 @@ def dfs_ancestors(node: str, ancestors: Dict[str, Set[str]],
                     dfs_ancestors(listener_name, ancestors, visited, flow)
 
 
-def build_parent_children_dict(flow: Flow) -> Dict[str, List[str]]:
+def build_parent_children_dict(flow: Flow[Any]) -> Dict[str, List[str]]:
     """Build a dictionary mapping each node to its list of child nodes.
     
     Maps both regular trigger methods to their listeners and router
@@ -196,7 +196,7 @@ def build_parent_children_dict(flow: Flow) -> Dict[str, List[str]]:
         dict[str, list[str]]: Dictionary mapping each method name to a
             sorted list of its child method names
     """
-    parent_children = {}
+    parent_children: Dict[str, List[str]] = {}
 
     # Map listeners to their trigger methods
     for listener_name, (_, trigger_methods) in flow._listeners.items():

src/crewai/flow/visualization_utils.py

@@ -2,8 +2,11 @@ import ast
 import inspect
 import os
 from pathlib import Path
-from typing import Dict, Optional, Tuple
+from typing import Any, Callable, Dict, Optional, Tuple, cast
 
+from pyvis.network import Network
+
+from crewai.flow.flow import Flow
 from .core_flow_utils import is_ancestor
 from .flow_visual_utils import (
     build_ancestor_dict,
@@ -13,7 +16,7 @@ from .flow_visual_utils import (
 from .path_utils import safe_path_join, validate_file_path
 
 
-def method_calls_crew(method: callable) -> bool:
+def method_calls_crew(method: Callable[..., Any]) -> bool:
     """Check if the method contains a .crew() call in its implementation.
     
     Analyzes the method's source code using AST to detect if it makes any
@@ -65,7 +68,7 @@ def method_calls_crew(method: callable) -> bool:
     return visitor.found
 
 
-def add_nodes_to_network(net: object, flow: object, 
+def add_nodes_to_network(net: Network, flow: Flow[Any], 
                      node_positions: Dict[str, Tuple[float, float]], 
                      node_styles: Dict[str, dict],
                      output_dir: Optional[str] = None) -> None:
@@ -169,8 +172,8 @@ def add_nodes_to_network(net: object, flow: object,
         )
 
 
-def compute_positions(flow: object, node_levels: dict[str, int], 
-                   y_spacing: float = 150, x_spacing: float = 150) -> dict[str, tuple[float, float]]:
+def compute_positions(flow: Flow[Any], node_levels: Dict[str, int], 
+                   y_spacing: float = 150, x_spacing: float = 150) -> Dict[str, Tuple[float, float]]:
     if not hasattr(flow, '_methods'):
         raise ValueError("Invalid flow object: missing '_methods' attribute")
     if not isinstance(node_levels, dict):
@@ -218,7 +221,7 @@ def compute_positions(flow: object, node_levels: dict[str, int],
     return node_positions
 
 
-def add_edges(net: object, flow: object, 
+def add_edges(net: Network, flow: Flow[Any], 
             node_positions: Dict[str, Tuple[float, float]], 
             colors: Dict[str, str],
             asset_dir: Optional[str] = None) -> None: