⚡️ Speed up function first_leaf by 12% in src/black/nodes.py

[codeflash-ai]

📄 first_leaf in src/black/nodes.py

✨ Performance Summary:

• Speed Increase: 📈 12% (0.12x faster)
• Runtime Reduction: ⏱️ From 16.7 microseconds down to 14.9 microseconds (best of 77 runs)

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📝 Explanation and details

Here's a more efficient and optimized version of the same code, focusing on reducing unnecessary overheads and redundant assertions.

Changes made to improve efficiency.

1. Simplified the __init__ method by removing redundant checks and assignments. For instance, context and prefix assignments are handled in a more compact manner.
2. Avoided mutable default arguments in __init__ by using None and then assigning appropriately.
3. Used in-place comparison in self._eq to slightly reduce the overhead.
4. Flattened the recursion in first_leaf into a loop to avoid Python's recursion limit and reduce overhead.

These changes should help in speeding up the runtime and slightly optimizing the memory usage.

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✅ Correctness verification

The new optimized code was tested for correctness. The results are listed below:

Test	Status	Details
⚙️ Existing Unit Tests	🔘 None Found
🌀 Generated Regression Tests	✅ 11 Passed	See below
⏪ Replay Tests	🔘 None Found
🔎 Concolic Coverage Tests	🔘 None Found
📊 Coverage	100.0%

🌀 Generated Regression Tests Details

Click to view details

from typing import Any, Optional, Union

# imports
import pytest  # used for our unit tests
from black.nodes import first_leaf
from blib2to3.pytree import Leaf, Node

# function to test
LN = Union[Leaf, Node]

class Node:
    """Concrete implementation for non-leaf nodes."""

    def __init__(self, children: list[LN]) -> None:
        self.children = children
from black.nodes import first_leaf


# unit tests
def test_simple_leaf_node():
    # Test case: input is a single Leaf node
    leaf = Leaf(type=1, value="leaf")
    codeflash_output = first_leaf(leaf)

def test_simple_node_with_one_leaf_child():
    # Test case: input is a Node with one Leaf child
    leaf = Leaf(type=1, value="leaf")
    node = Node(children=[leaf])
    codeflash_output = first_leaf(node)


def test_node_with_nested_nodes_and_leaves():
    # Test case: input is a Node with nested Nodes and Leaves
    leaf = Leaf(type=1, value="leaf")
    inner_node = Node(children=[leaf])
    outer_node = Node(children=[inner_node])
    codeflash_output = first_leaf(outer_node)


def test_deeply_nested_structure():
    # Test case: input is a Node with a deeply nested structure
    leaf = Leaf(type=1, value="leaf")
    deep_node = Node(children=[Node(children=[Node(children=[leaf])])])
    codeflash_output = first_leaf(deep_node)


def test_edge_case_empty_node():
    # Test case: edge case with an empty Node
    node = Node(children=[])
    codeflash_output = first_leaf(node)

def test_edge_case_mixed_children():
    # Test case: edge case with mixed Leaf and Node children
    leaf = Leaf(type=1, value="leaf")
    inner_node = Node(children=[leaf])
    outer_node = Node(children=[inner_node, leaf])
    codeflash_output = first_leaf(outer_node)



from typing import Any, Optional, Union

# imports
import pytest  # used for our unit tests
from black.nodes import first_leaf
from blib2to3.pytree import Leaf, Node

# function to test
LN = Union[Leaf, Node]
from black.nodes import first_leaf

# unit tests

def test_single_leaf_node():
    # Test with a single Leaf node
    leaf = Leaf(1, "value")
    codeflash_output = first_leaf(leaf)









def test_non_leaf_non_node_input():
    # Test with an invalid input that is neither a Leaf nor a Node
    with pytest.raises(AttributeError):
        first_leaf("invalid")

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