test-gen

name	test-gen
description	Generate pytest-discoverable unit tests for LeetCode solution files. Use when adding tests to a solution, converting bare asserts to test functions, or creating test cases for a problem.

Context

• Solutions live in leetpattern/python/{range}/ as {number}_{name}.py
• Tests are inline in the same solution file (no separate test files)
• pytest discovers def test_* functions in files matching [0-9][0-9][0-9][0-9]_*.py
• Utility imports available: from leetpattern.utils import LinkedList, ListNode, Trie, TrieNode, LPS

Test Format

Append a def test_<function_name>(): function at the bottom of the solution file. Each test function should contain multiple assert statements covering different cases.

def test_<function_name>():
    # basic cases
    assert <function_name>(<input>) == <expected>
    # edge cases
    assert <function_name>(<edge_input>) == <edge_expected>

Rules

1. The test function name must start with test_ followed by the solution function name (snake_case).
2. Include at least 3 test cases: a basic case, an edge case (empty input, single element, etc.), and a non-trivial case.
3. If the solution uses a class with multiple methods (e.g., longestPalindrome.dp), create one test function per method: def test_<class>_<method>():.
4. For linked list problems, use LinkedList and ListNode from leetpattern.utils for construction and comparison.
5. For tree problems, use binarytree or the project's tree utilities for construction.
6. If the file already has bare assert statements or if __name__ blocks with test logic, convert them into proper def test_* functions and remove the old code.
7. Do not add duplicate test functions if a valid def test_* already exists — extend it instead.
8. Keep test cases concise. Use inline values, not fixtures.
9. If a problem has multiple valid outputs (e.g., "return any valid answer"), use assert result in [<valid1>, <valid2>] or assert sorted(result) == sorted(expected).
10. Add the LeetCode problem URL as a comment above the test function: # https://leetcode.com/problems/<slug>/.