py-flow-check

Static analyzer for logical flow bugs in Python.

It tries to catch:

• unreachable code after return or raise
• always true or always false conditions like if True
• unreachable or redundant conditions in if/elif chains (best with numeric comparisons)
• functions that do not return on every path
• variables that might be used before assignment on some paths

Install

pip install py-flow-check

CLI

flowcheck path/to/file.py

JSON output (useful for CI):

flowcheck --json path/to/file.py

Exit code:

• 0 if no issues
• 1 if issues found

Python API

from flowcheck import analyze

code = """
def f(flag):
    if flag:
        x = 1
    return x
"""
for issue in analyze(code):
    print(issue.format())