mcp-server-semgrep/semgrep-rules/python/correctness/check-is-none-explicitly.yaml

MCP Server for Semgrep Integration - static code analysis with AI

rules:
- id: check-is-none-explicitly
  pattern-either:
  - pattern: $X and $X == 0
  - pattern: $X.get($FIELD) and $X[$FIELD] == 0
  fix: ($X != None) and $X == 0
  message: This expression will always return False because 0 is a false-y value.
    So if $X is 0, then the first part of this expression will return False but if
    it is not, the second part will return False. Perhaps you meant to check if $X
    was None explicitly.
  languages:
  - python
  severity: WARNING
  metadata:
    category: correctness
    technology:
    - none
    references:
    - https://www.freecodecamp.org/news/truthy-and-falsy-values-in-python/