rules:
- id: writing-to-file-in-read-mode
  message: >-
    The file object '$FD' was opened in read mode, but is being
    written to. This will cause a runtime error.
  patterns:
  - pattern-either:
    - pattern-inside: |
        $FD = open($NAME, "r", ...)
        ...
    - pattern-inside: |
        $FD = open($NAME, "rb", ...)
        ...
    - pattern-inside: |
        with open($NAME, "r", ...) as $FD:
          ...
    - pattern-inside: |
        with open($NAME, "rb", ...) as $FD:
          ...
  - pattern: $FD.write(...)
  severity: ERROR
  languages:
  - python
  metadata:
    category: correctness
    technology:
    - python