Need help with unit test

Ruby
1

Hi all,
I’m a newbie to Ruby. I tried the below code but don’t understand why
the “test_typecheck” does not give any error. Could someone shed a light
to my problem ?
thanks
tony

test1.rb

require ‘test/unit’

class SimpleNumber

def initialize( num )
raise “input must be a number” unless num.is_a?(Numeric)
@x = num
end

def add( y )
@x + y
end

def multiply( y )
@x * y
end

end

#error = SimpleNumber.new(‘abc’) <== this raises exeption

class TestSimpleNumber < Test::Unit::TestCase

def test_simple
assert_equal(4, SimpleNumber.new(2).add(2) )
assert_equal(4, SimpleNumber.new(2).multiply(2) )
end

def test_typecheck
assert_raise( RuntimeError ) { SimpleNumber.new(‘abc’) }
end
end

=====================
I would expect to see assertion failure for test_typecheck but it does
not give any.

output

Run options:

Running tests:

…

Finished tests in 0.006836s, 292.5688 tests/s, 438.8531 assertions/s.

2 tests, 3 assertions, 0 failures, 0 errors, 0 skips

2

raise “string” does raise a RuntimeError. If you want a custom
exception class, you need to create it first:

ruby-1.9.3-p0 > begin; raise “hello world”; rescue Exception => e;
puts “rescued #{e.class}”; end
rescued RuntimeError

ruby-1.9.3-p0 > class BadValue < Exception; end

ruby-1.9.3-p0 > begin; raise BadValue.new(“hello world”); rescue
Exception => e; puts “rescued #{e.class}”; end
rescued BadValue

martin

3

Thi N. wrote in post #1058895:

I would expect to see assertion failure for test_typecheck but it does
not give any.

Why do you expect to see assertion failure?

As far as I can see, SimpleNumber.new(‘abc’) raises a RuntimeError, and
you’re catching it with assert_raise(RuntimeError), i.e. you’re
correctly testing that your code raises an error.