Test::Builder::Tester
Test::Builder::TesterUser Contributed Perl DocumentatTest::Builder::Tester(3)
NAME
Test::Builder::Tester - test testsuites that have been built with
Test::Builder
SYNOPSIS
use Test::Builder::Tester tests => 1;
use Test::More;
test_out("not ok 1 - foo");
test_fail(+1);
fail("foo");
test_test("fail works");
DESCRIPTION
A module that helps you test testing modules that are built with
Test::Builder.
The testing system is designed to be used by performing a three step
process for each test you wish to test. This process starts with
using "test_out" and "test_err" in advance to declare what the test-
suite you are testing will output with Test::Builder to stdout and
stderr.
You then can run the test(s) from your test suite that call
Test::Builder. At this point the output of Test::Builder is safely
captured by Test::Builder::Tester rather than being interpreted as
real test output.
The final stage is to call "test_test" that will simply compare what
you predeclared to what Test::Builder actually outputted, and report
the results back with a "ok" or "not ok" (with debugging) to the nor-
mal output.
Functions
These are the six methods that are exported as default.
test_out
test_err
Procedures for predeclaring the output that your test suite is
expected to produce until "test_test" is called. These procedures
automatically assume that each line terminates with "\n". So
test_out("ok 1","ok 2");
is the same as
test_out("ok 1\nok 2");
which is even the same as
test_out("ok 1");
test_out("ok 2");
Once "test_out" or "test_err" (or "test_fail" or "test_diag") have
been called once all further output from Test::Builder will be
captured by Test::Builder::Tester. This means that your will not
be able perform further tests to the normal output in the normal
way until you call "test_test" (well, unless you manually meddle
with the output filehandles)
test_fail
Because the standard failure message that Test::Builder produces
whenever a test fails will be a common occurrence in your test
error output, and because has changed between Test::Builder ver-
sions, rather than forcing you to call "test_err" with the string
all the time like so
test_err("# Failed test ($0 at line ".line_num(+1).")");
"test_fail" exists as a convenience function that can be called
instead. It takes one argument, the offset from the current line
that the line that causes the fail is on.
test_fail(+1);
This means that the example in the synopsis could be rewritten
more simply as:
test_out("not ok 1 - foo");
test_fail(+1);
fail("foo");
test_test("fail works");
test_diag
As most of the remaining expected output to the error stream will
be created by Test::Builder’s "diag" function,
Test::Builder::Tester provides a convience function "test_diag"
that you can use instead of "test_err".
The "test_diag" function prepends comment hashes and spacing to
the start and newlines to the end of the expected output passed to
it and adds it to the list of expected error output. So, instead
of writing
test_err("# Couldn’t open file");
you can write
test_diag("Couldn’t open file");
Remember that Test::Builder’s diag function will not add newlines
to the end of output and test_diag will. So to check
Test::Builder->new->diag("foo\n","bar\n");
You would do
test_diag("foo","bar")
without the newlines.
test_test
Actually performs the output check testing the tests, comparing
the data (with "eq") that we have captured from Test::Builder
against that that was declared with "test_out" and "test_err".
This takes name/value pairs that effect how the test is run.
title (synonym ’name’, ’label’)
The name of the test that will be displayed after the "ok" or
"not ok".
skip_out
Setting this to a true value will cause the test to ignore if
the output sent by the test to the output stream does not
match that declared with "test_out".
skip_err
Setting this to a true value will cause the test to ignore if
the output sent by the test to the error stream does not match
that declared with "test_err".
As a convience, if only one argument is passed then this argument
is assumed to be the name of the test (as in the above examples.)
Once "test_test" has been run test output will be redirected back
to the original filehandles that Test::Builder was connected to
(probably STDOUT and STDERR,) meaning any further tests you run
will function normally and cause success/errors for Test::Harness.
line_num
A utility function that returns the line number that the function
was called on. You can pass it an offset which will be added to
the result. This is very useful for working out the correct text
of diagnostic functions that contain line numbers.
Essentially this is the same as the "__LINE__" macro, but the
"line_num(+3)" idiom is arguably nicer.
In addition to the six exported functions there there exists one func-
tion that can only be accessed with a fully qualified function call.
color
When "test_test" is called and the output that your tests generate
does not match that which you declared, "test_test" will print out
debug information showing the two conflicting versions. As this
output itself is debug information it can be confusing which part
of the output is from "test_test" and which was the original out-
put from your original tests. Also, it may be hard to spot things
like extraneous whitespace at the end of lines that may cause your
test to fail even though the output looks similar.
To assist you, if you have the Term::ANSIColor module installed
(which you should do by default from perl 5.005 onwards),
"test_test" can colour the background of the debug information to
disambiguate the different types of output. The debug output will
have it’s background coloured green and red. The green part rep-
resents the text which is the same between the executed and actual
output, the red shows which part differs.
The "color" function determines if colouring should occur or not.
Passing it a true or false value will enable or disable colouring
respectively, and the function called with no argument will return
the current setting.
To enable colouring from the command line, you can use the
Text::Builder::Tester::Color module like so:
perl -Mlib=Text::Builder::Tester::Color test.t
Or by including the Test::Builder::Tester::Color module directly
in the PERL5LIB.
BUGS
Calls "<Test::Builder-"no_ending>> turning off the ending tests. This
is needed as otherwise it will trip out because we’ve run more tests
than we strictly should have and it’ll register any failures we had
that we were testing for as real failures.
The color function doesn’t work unless Term::ANSIColor is installed
and is compatible with your terminal.
Bugs (and requests for new features) can be reported to the author
though the CPAN RT system: <http://rt.cpan.org/NoAuth/Report-
Bug.html?Queue=Test-Builder-Tester>
AUTHOR
Copyright Mark Fowler <mark@twoshortplanks.com> 2002, 2004.
Some code taken from Test::More and Test::Catch, written by by Michael
G Schwern <schwern@pobox.com>. Hence, those parts Copyright Micheal G
Schwern 2001. Used and distributed with permission.
This program is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.
NOTES
This code has been tested explicitly on the following versions of
perl: 5.7.3, 5.6.1, 5.6.0, 5.005_03, 5.004_05 and 5.004.
Thanks to Richard Clamp <richardc@unixbeard.net> for letting me use
his testing system to try this module out on.
SEE ALSO
Test::Builder, Test::Builder::Tester::Color, Test::More.
perl v5.8.8 2008-11-09 Test::Builder::Tester(3)
