pi-lens/rules/tree-sitter-queries/ruby/ruby-rescue-exception.yml

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id: ruby-rescue-exception
name: Rescue Exception Base Class
severity: warning
category: reliability
defect_class: correctness
inline_tier: blocking
language: ruby

message: "rescue Exception catches SystemExit and Interrupt — use StandardError"

description: |
  'rescue Exception' catches EVERYTHING including system signals:
  - Interrupt (Ctrl+C)
  - SystemExit (exit/abort)
  - SignalException (kill signals)
  
  This makes the process impossible to kill gracefully.
  
  ✅ FIX: Use StandardError or a specific exception class:
    rescue StandardError => e   # safe: catches user errors
    rescue ArgumentError, TypeError => e  # specific

query: |
  (rescue
    exceptions: (exceptions
      (constant) @EXCEP)
    (#eq? @EXCEP "Exception"))

metavars:
  - EXCEP

has_fix: false

tags:
  - reliability
  - error-handling
  - signals

examples:
  bad: |
    begin
      risky_operation
    rescue Exception => e   # catches SystemExit, Interrupt!
      puts e.message
    end
  
  good: |
    begin
      risky_operation
    rescue StandardError => e
      logger.error(e.message)
      raise
    end