python.lang.correctness.exceptions.exceptions.raise-not-base-exception

Community Favorite
profile photo of semgrepsemgrep
Author
46,927
Download Count*
LGPL Commons Clause
License

In Python3, a runtime TypeError will be thrown if you attempt to raise an object or class which does not inherit from BaseException

Run Locally

Run in CI

Semgrep CI docs

Defintion

Edit RuleView Source
Open in Playground 
rules:
  - id: raise-not-base-exception
    message: In Python3, a runtime `TypeError` will be thrown if you attempt to
      raise an object or class which does not inherit from `BaseException`
    languages:
      - python
    severity: ERROR
    pattern-either:
      - pattern: raise "..."
      - pattern: |
          $X: BaseException
          raise $X(...)
      - patterns:
          - pattern: raise $EXCEPTION
          - metavariable-regex:
              metavariable: $EXCEPTION
              regex: "[0-9]*\\.?[0-9]+"
    metadata:
      category: correctness
      technology:
        - python
      license: Commons Clause License Condition v1.0[LGPL-2.1-only]

Examples

exceptions.py

# ruleid:raise-not-base-exception
raise "error here"

# ruleid:raise-not-base-exception
raise 5


class Foobar:
    x = 5


# todoruleid:raise-not-base-exception
raise Foobar()


class Foobar2(BaseException):
    x = 5


# ok:raise-not-base-exception
raise Foobar2()

# ok:raise-not-base-exception
raise Exception()