Bug #20795: Timeout method doesn't check for negative time values

• Status: Open
• Assignee: -
• Target version: -
• ruby -v: 3.1.0
• Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN

[kanakchaudhari12 (kanak chaudhari)]

require 'timeout'

# Case 1: Negative timeout with quick execution
Timeout.timeout(-5) do
  puts "This should not execute"
end

# Case 2: Negative timeout with sleep
Timeout.timeout(-5) do
  sleep(10)
end

Potential issues with current behaviour:

• Inconsistency: The behaviour differs based on the block's content, which may not be immediately apparent
• Silent failure: The negative timeout is silently ignored, potentially masking logical errors in the calling code.
• Unexpected source of error: one might expect the timeout method to validate its input, rather than relying on methods called within the block to catch invalid time values.

I suggest this change for the consistent behaviour regardless of code-block as well as the clear indication of the source of the error

def timeout(sec, klass = nil, message = nil, &block)
  raise ArgumentError, "timeout must be positive" if sec.is_a?(Numeric) && sec < 0
  # ...
end

[Eregon (Benoit Daloze)]

Could you make a PR to https://github.com/ruby/timeout ? (or if not open an issue there?)