From: eregontp@...
Date: 2015-01-16T12:34:48+00:00
Subject: [ruby-core:67628] [ruby-trunk - Bug #10745] Special combinations of parameters in assert_equal (test/unit) may cause exceptions

Issue #10745 has been updated by Benoit Daloze.


Tsuyoshi Sawada wrote:
> An interesting case. `assert_equal` seems to be assuming that the `==` method on the relevant class (`IPAddr#==` here) does not raise an error, but that should not be taken for granted. It should be wrapped in a rescue block.

I disagree, the exception is more useful as an error than just assert_equal returning false.

Kouhei Sutou wrote:
> I think that it should be fixed in ipaddr.

Indeed, the error from IPAddr could be clearer,

----------------------------------------
Bug #10745: Special combinations of parameters in assert_equal (test/unit) may cause exceptions
https://bugs.ruby-lang.org/issues/10745#change-51050

* Author: Herwin .
* Status: Rejected
* Priority: Low
* Assignee: 
* ruby -v: 2.1.2p95
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
~~~ruby
require 'test/unit'
require 'ipaddr'

class TestX < Test::Unit::TestCase
  def test_x
    assert_equal([IPAddr.new('1.2.3.4')], [[1,2,3]])
  end
end
~~~

This results in the following trace:

~~~
NoMethodError: undefined method `to_i' for [1, 2, 3]:Array
    /usr/lib/ruby/2.1.0/ipaddr.rb:471:in `initialize'
    /usr/lib/ruby/2.1.0/ipaddr.rb:516:in `new'
    /usr/lib/ruby/2.1.0/ipaddr.rb:516:in `coerce_other'
    /usr/lib/ruby/2.1.0/ipaddr.rb:150:in `=='
    /usr/lib/ruby/2.1.0/test/unit/assertions.rb:250:in `=='
    /usr/lib/ruby/2.1.0/test/unit/assertions.rb:250:in `assert_equal'
~~~

I don't think the `assert_equal` is supposed to throw these kind of errors



-- 
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