locally redefining subroutine in module

Jasper has asked for the wisdom of the Perl Monks concerning the following question:

Monkies,

In a test I don't want to call the real subroutine for something, so I am overwriting the subroutine. I was hoping there would be a way to locally redefine the sub, but can't think of one. The following code works, but is a bit of a kludge. Is there a better way?

sub Foo::new {
  require MockFoo;
  return MockFoo->new();
}

# blah blah blah - tests in here

eval `cat Foo.pm`; # borrowed from 'Programming Perl'
                   # to reestablish the original meaning
[download]

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Re: locally redefining subroutine in module by Corion (Patriarch) on Jun 30, 2004 at 10:09 UTC
There is a much cleaner and easier way: `{ local *Foo::new = sub { require MockFoo; return MockFoo->new; }; ... tests ... }; # Foo::new is restored to its old value` [download]	[reply] [d/l]
Re^2: locally redefining subroutine in module by Jasper (Chaplain) on Jun 30, 2004 at 10:16 UTC
Thanks, Corion. Also: `local Foo::new = MockFoo::new;`. Dunno why I hadn't tried that..	[reply] [d/l]
Re: locally redefining subroutine in module by adrianh (Chancellor) on Jun 30, 2004 at 10:19 UTC
You can use `local` instead. See Micro Mocking: using local to help test subs for some examples.	[reply] [d/l]
Re^2: locally redefining subroutine in module by Jasper (Chaplain) on Jun 30, 2004 at 10:49 UTC
So you're telling me that as well as being ignorant of perl, I am also useless at searching. :)	[reply]