Test::Builder::Tester(3p) Perl Programmers Reference Guide #
Test::Builder::Tester(3p) Perl Programmers Reference Guide
NNAAMMEE #
Test::Builder::Tester - test testsuites that have been built with
Test::Builder
SSYYNNOOPPSSIISS #
use Test::Builder::Tester tests => 1;
use Test::More;
test_out("not ok 1 - foo");
test_fail(+1);
fail("foo");
test_test("fail works");
DDEESSCCRRIIPPTTIIOONN #
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 testsuite 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 normal
output.
FFuunnccttiioonnss 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, all further output from Test::Builder will be captured
by Test::Builder::Tester. This means that you 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 it has changed between Test::Builder versions,
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 convenience 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
what 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 convenience, 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 exists one function 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 output 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 "test_test" can colour the background of the debug
information to disambiguate the different types of output. The debug
output will have its background coloured green and red. The green
part represents 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.
BBUUGGSS #
Test::Builder::Tester does not handle plans well. It has never done
anything special with plans. This means that plans from outside
Test::Builder::Tester will effect Test::Builder::Tester, worse plans when
using Test::Builder::Tester will effect overall testing. At this point
there are no plans to fix this bug as people have come to depend on it,
and Test::Builder::Tester is now discouraged in favor of
"Test2::API::intercept()". See
<https://github.com/Test-More/test-more/issues/667>
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 compatible with
your terminal. Additionally, Win32::Console::ANSI must be installed on
windows platforms for color output.
Bugs (and requests for new features) can be reported to the author though
GitHub: <https://github.com/Test-More/test-more/issues>
AAUUTTHHOORR #
Copyright Mark Fowler <mark@twoshortplanks.com> 2002, 2004.
Some code taken from Test::More and Test::Catch, written 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.
MMAAIINNTTAAIINNEERRSS #
Chad Granum <exodist@cpan.org>
NNOOTTEESS #
Thanks to Richard Clamp <richardc@unixbeard.net> for letting me use his
testing system to try this module out on.
SSEEEE AALLSSOO #
Test::Builder, Test::Builder::Tester::Color, Test::More.
perl v5.36.3 2023-02-15 Test::Builder::Tester(3p)