# flake8-cognitive-complexity

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An extension for flake8 that validates cognitive functions complexity.

Cognitive complexity is analog of cyclomatic complexity, that measure
how difficult to understand piece of code. Introduced by [G. Ann Campbell](https://github.com/ganncamp)
and currently used by SonarSource, CodeClimate and others.
You can find more readings about cognitive complexity in
[cognitive-complexity readme file](https://github.com/Melevir/cognitive_complexity/blob/master/README.md#what-is-cognitive-complexity).

Default complexity is 7, can be configured via `--max-cognitive-complexity` option.

## Installation

```terminal
pip install flake8-cognitive-complexity
```

## Example

```python
def f(a, b):
    if a:
        for i in range(b):
            if b:
                return 1
```

Usage:

```terminal
$ flake8 --max-cognitive-complexity=3 test.py
text.py:1:5: CCR001 Cognitive complexity is too high (6 > 3)
```

Tested on Python 3.7.x and flake8 3.7.8.

## Error codes

| Error code |                     Description          |
|:----------:|:----------------------------------------:|
|   CCR001   | Cognitive complexity is too high (X > Y) |

An extension for flake8 that validates cognitive functions complexity. 

flake8-cognitive-complexity

An extension for flake8 that validates cognitive functions complexity

Melevir

(Experimental) An ambiguous license classifier was found.

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Ambiguous License Classifier

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Bad text encoding

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Bad semver

Package has dependencies with an invalid semantic version. This could be a sign of beta, low quality, or unmaintained dependencies.

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Bad dependency semver

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Bidirectional unicode control characters

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What is bin script confusion?

Bin script confusion

This Chrome extension includes content scripts that execute JavaScript on specified websites.

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Chrome Extension Content Script

This Chrome extension requests host permissions to access specific websites or domains.

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Chrome Extension Host Permission

This Chrome extension requests permissions to access browser APIs, user data, or system features.

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Chrome Extension Permission

This Chrome extension requests wildcard host permissions that grant broad access to websites.

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Chrome Extension Wildcard Host Permission

Semantic versions published out of chronological order.

What is a chronological version anomaly?

Chronological version anomaly

Project maintainer's SSH key has been compromised.

What is a compromised SSH key?

Compromised SSH key

(Experimental) Copyleft license information was found.

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Copyleft License

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Title

Critical CVE

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High CVE

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Debug access

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Deprecated

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Deprecated SPDX exception

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Deprecated license

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Possible typosquat attack

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Dynamic require

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Empty package

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Environment variable access

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File dependency

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Filesystem access

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Wildcard dependency

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Git dependency

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GitHub dependency

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AI-detected potential security risk

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Native code

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High entropy strings

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Unicode homoglyphs

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HTTP dependency

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Install scripts

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Invalid manifest file

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What are invisible characters?

Invisible chars

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License change

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License exception

This package is not allowed per your license policy. Review the package's license to ensure compliance.

What is a license policy violation?

License Policy Violation

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Long strings

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Major refactor

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Known malware

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Manifest confusion

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Medium CVE

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Low CVE

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Modified license exception

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Modified license

What is network access?

Network access

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New author

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Why is contributor and author data important?

No contributors or author data

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No bug tracker

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flake8-cognitive-complexity