mcp-server-semgrep/semgrep-rules/bash/lang/best-practice/useless-cat.yaml

MCP Server for Semgrep Integration - static code analysis with AI

rules:
- id: useless-cat
  pattern-either:
  - pattern: |
      cat | ...
  - patterns:
    - pattern: |
        cat $ARG | ...
    - pattern-not: |
        cat ${$SEVERAL_FILES} | ...
  - pattern: |
      ... | cat
  - pattern: |
      ... | cat | ...
  # TODO: autofix, once we support $...ARGS
  message: >-
    Useless call to 'cat' in a pipeline. Use '<' and '>' for any command
    to read from a file or write to a file.
  metadata:
    references:
    - https://github.com/koalaman/shellcheck/wiki/SC2002
    category: best-practice
    technology:
    - bash
  severity: WARNING
  languages:
  - bash