Test::Command(3p)

NAME
Test::Command - Test routines for external commands

VERSION
Version 0.11

SYNOPSIS
Test the exit status, signal, STDOUT or STDERR of an external command.

   use Test::Command tests => 11;

   ## testing exit status

   my $cmd = 'true';

   exit_is_num($cmd, 0);
   exit_cmp_ok($cmd, '<', 10);

   $cmd = 'false';

   exit_isnt_num($cmd, 0);

   ## testing terminating signal

   $cmd = 'true';

   signal_is_num($cmd, 0);

   ## testing STDOUT

   $cmd         = [qw/ echo out /];  ## run as "system @$cmd"
   my $file_exp = 'echo_stdout.exp';

   stdout_is_eq($cmd, "out\n");
   stdout_isnt_eq($cmd, "out");
   stdout_is_file($cmd, $file_exp);

   ## testing STDERR

   $cmd = 'echo err >&2';

   stderr_like($cmd, /err/);
   stderr_unlike($cmd, /rre/);
   stderr_cmp_ok($cmd, 'eq', "err\n");

   ## run-once-test-many-OO-style
   ## the first test lazily runs command
   ## the second test uses cached results

   my $echo_test = Test::Command->new( cmd => 'echo out' );

   $echo_test->exit_is_num(0);
   $echo_test->signal_is_num(0);
   $echo_test->stdout_is_eq("out\n");

   ## force a re-run of the command

   $echo_test->run;

   ## arbitrary results inspection

   is( $echo_test->exit_value, 0,         'echo exit' );
   is( $echo_test->signal_value, undef,   'echo signal' );
   is( $echo_test->stdout_value, "out\n", 'echo stdout' );
   is( $echo_test->stderr_value, '',      'echo stderr' );
   is( -s $echo_test->stdout_file, 4,     'echo stdout file size' );
   is( -s $echo_test->stderr_file, 0,     'echo stderr file size' );

DESCRIPTION
"Test::Command" intends to bridge the gap between the well tested functions and objects you choose and their usage in your programs. By examining the exit status, terminating signal, STDOUT and STDERR of your program you can determine if it is behaving as expected.

This includes testing the various combinations and permutations of options and arguments as well as the interactions between the various functions and objects that make up your program.

The various test functions below can accept either a command string or an array reference for the first argument. If the command is expressed as a string it is passed to "system" as is. If the command is expressed as an array reference it is dereferenced and passed to "system" as a list. See '"perldoc -f system"' for how these may differ.

The final argument for the test functions, $name, is optional. By default the $name is a concatenation of the test function name, the command string and the expected value. This construction is generally sufficient for identifying a failing test, but you may always specify your own $name if desired.

Any of the test functions can be used as instance methods on a "Test::Command" object. This is done by dropping the initial $cmd argument and instead using arrow notation.

All of the following "exit_is_num" calls are equivalent.

   exit_is_num('true', 0);
   exit_is_num('true', 0, 'exit_is_num: true, 0');
   exit_is_num(['true'], 0);
   exit_is_num(['true'], 0, 'exit_is_num: true, 0');

   my $cmd = Test::Command->new( cmd => 'true' );

   exit_is_num($cmd, 0);
   exit_is_num($cmd, 0, 'exit_is_num: true, 0');
   $cmd->exit_is_num(0);
   $cmd->exit_is_num(0, 'exit_is_num: true, 0');

   $cmd = Test::Command->new( cmd => ['true'] );

   exit_is_num($cmd, 0);
   exit_is_num($cmd, 0, 'exit_is_num: true, 0');
   $cmd->exit_is_num(0);
   $cmd->exit_is_num(0, 'exit_is_num: true, 0');

EXPORT
All of the test functions mentioned below are exported by default.

METHODS

  new
   my $test_cmd_obj = Test::Command->new( cmd => $cmd )

This constructor creates and returns a "Test::Command" object. Use this to test multiple aspects of a single command execution while avoiding repeatedly running commands which are slow or resource intensive.

The "cmd" parameter can accept either a string or an array reference for its value. The value is dereferenced if necessary and passed directly to the "system" builtin.

  run
   $test_cmd_obj->run;

This instance method forces the execution of the command specified by the invocant.

You only need to call this when you wish to re-run a command since the first test method invoked will lazily execute the command if necessary. However, if the state of your inputs has changed and you wish to re-run the command, you may do so by invoking this method at any point between your tests.

FUNCTIONS

  Testing Exit Status
The test routines below compare against the exit status of the executed command right shifted by 8 (that is, "$? >> 8").

exit_value

   exit_value($cmd)

Return the exit status of the command. Useful for performing arbitrary tests not covered by this module.

exit_is_num

   exit_is_num($cmd, $exp_num, $name)

If the exit status of the command is numerically equal to the expected number, this passes. Otherwise it fails.

exit_isnt_num

   exit_isnt_num($cmd, $unexp_num, $name)

If the exit status of the command is not numerically equal to the given number, this passes. Otherwise it fails.

exit_cmp_ok

   exit_cmp_ok($cmd, $op, $operand, $name)

If the exit status of the command is compared with the given operand using the given operator, and that operation returns true, this passes. Otherwise it fails.

exit_is_defined

   exit_is_defined($cmd, $name)

If the exit status of the command is defined, this passes. Otherwise it fails. A defined exit status indicates that the command exited normally by calling exit() or running off the end of the program.

exit_is_undef

   exit_is_undef($cmd, $name)

If the exit status of the command is not defined, this passes. Otherwise it fails. An undefined exit status indicates that the command likely exited due to a signal.

  Testing Terminating Signal
The test routines below compare against the lower 8 bits of the exit status of the executed command.

signal_value

   signal_value($cmd)

Return the signal code of the command. Useful for performing arbitrary tests not covered by this module.

signal_is_num

   signal_is_num($cmd, $exp_num, $name)

If the terminating signal of the command is numerically equal to the expected number, this passes. Otherwise it fails.

signal_isnt_num

   signal_isnt_num($cmd, $unexp_num, $name)

If the terminating signal of the command is not numerically equal to the given number, this passes. Otherwise it fails.

signal_cmp_ok

   signal_cmp_ok($cmd, $op, $operand, $name)

If the terminating signal of the command is compared with the given operand using the given operator, and that operation returns true, this passes. Otherwise it fails.

signal_is_defined

   signal_is_defined($cmd, $name)

If the terminating signal of the command is defined, this passes. Otherwise it fails. A defined signal indicates that the command likely exited due to a signal.

signal_is_undef

   signal_is_undef($cmd, $name)

If the terminating signal of the command is not defined, this passes. Otherwise it fails. An undefined signal indicates that the command exited normally by calling exit() or running off the end of the program.

  Testing STDOUT
Except where specified, the test routines below treat STDOUT as a single slurped string.

stdout_value

   stdout_value($cmd)

Return the STDOUT of the command. Useful for performing arbitrary tests not covered by this module.

stdout_file

   stdout_file($cmd)

Return the file name containing the STDOUT of the command. Useful for performing arbitrary tests not covered by this module.

stdout_is_eq

   stdout_is_eq($cmd, $exp_string, $name)

If the STDOUT of the command is equal (compared using "eq") to the expected string, then this passes. Otherwise it fails.

stdout_isnt_eq

   stdout_isnt_eq($cmd, $unexp_string, $name)

If the STDOUT of the command is not equal (compared using "eq") to the given string, this passes. Otherwise it fails.

stdout_is_num

   stdout_is_num($cmd, $exp_num, $name)

If the STDOUT of the command is equal (compared using "==") to the expected number, then this passes. Otherwise it fails.

stdout_isnt_num

   stdout_isnt_num($cmd, $unexp_num, $name)

If the STDOUT of the command is not equal (compared using "==") to the given number, this passes. Otherwise it fails.

stdout_like

   stdout_like($cmd, $exp_regex, $name)

If the STDOUT of the command matches the expected regular expression, this passes. Otherwise it fails.

stdout_unlike

   stdout_unlike($cmd, $unexp_regex, $name)

If the STDOUT of the command does not match the given regular expression, this passes. Otherwise it fails.

stdout_cmp_ok

   stdout_cmp_ok($cmd, $op, $operand, $name)

If the STDOUT of the command is compared with the given operand using the given operator, and that operation returns true, this passes. Otherwise it fails.

stdout_is_file

   stdout_is_file($cmd, $exp_file, $name)

If the STDOUT of the command is equal (compared using "eq") to the contents of the given file, then this passes. Otherwise it fails. Note that this comparison is performed line by line, rather than slurping the entire file.

  Testing STDERR
Except where specified, the test routines below treat STDERR as a single slurped string.

stderr_value

   stderr_value($cmd)

Return the STDERR of the command. Useful for performing arbitrary tests not covered by this module.

stderr_file

   stderr_file($cmd)

Return the file name containing the STDERR of the command. Useful for performing arbitrary tests not covered by this module.

stderr_is_eq

   stderr_is_eq($cmd, $exp_string, $name)

If the STDERR of the command is equal (compared using "eq") to the expected string, then this passes. Otherwise it fails.

stderr_isnt_eq

   stderr_isnt_eq($cmd, $unexp_string, $name)

If the STDERR of the command is not equal (compared using "eq") to the given string, this passes. Otherwise it fails.

stderr_is_num

   stderr_is_num($cmd, $exp_num, $name)

If the STDERR of the command is equal (compared using "==") to the expected number, then this passes. Otherwise it fails.

stderr_isnt_num

   stderr_isnt_num($cmd, $unexp_num, $name)

If the STDERR of the command is not equal (compared using "==") to the given number, this passes. Otherwise it fails.

stderr_like

   stderr_like($cmd, $exp_regex, $name)

If the STDERR of the command matches the expected regular expression, this passes. Otherwise it fails.

stderr_unlike

   stderr_unlike($cmd, $unexp_regex, $name)

If the STDERR of the command does not match the given regular expression, this passes. Otherwise it fails.

stderr_cmp_ok

   stderr_cmp_ok($cmd, $op, $operand, $name)

If the STDERR of the command is compared with the given operand using the given operator, and that operation returns true, this passes. Otherwise it fails.

stderr_is_file

   stderr_is_file($cmd, $exp_file, $name)

If the STDERR of the command is equal (compared using "eq") to the contents of the given file, then this passes. Otherwise it fails. Note that this comparison is performed line by line, rather than slurping the entire file.

AUTHOR
Daniel B. Boorstein, "<danboo at cpan.org>"

BUGS
Please report any bugs or feature requests to "bug-test-command at rt.cpan.org", or through the web interface at <http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Test-Command>. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SUPPORT
You can find documentation for this module with the perldoc command.

    perldoc Test::Command

You can also look for information at:

•   AnnoCPAN: Annotated CPAN documentation

    <http://annocpan.org/dist/Test-Command>

•   CPAN Ratings

    <http://cpanratings.perl.org/d/Test-Command>

•   RT: CPAN's request tracker

    <http://rt.cpan.org/NoAuth/Bugs.html?Dist=Test-Command>

•   Search CPAN

    <http://search.cpan.org/dist/Test-Command>

ACKNOWLEDGEMENTS
Test::Builder by Michael Schwern allowed me to focus on the specifics related to testing system commands by making it easy to produce proper test output.

COPYRIGHT & LICENSE
Copyright 2007 Daniel B. Boorstein, all rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

DEVELOPMENT IDEAS

•   create a tool that produces test scripts given a list of commands to run

•   optionally save the temp files with STDOUT and STDERR for user debugging

•   if user defines all options and sample arguments to basic command

    •   create tool to enumerate all possible means of calling program

    •   allow testing with randomized/permuted/collapsed opts and args

•   potential test functions:

    •   time_lt($cmd, $seconds)

    •   time_gt($cmd, $seconds)

    •   stdout_line_custom($cmd, \&code)

    •   stderr_line_custom($cmd, \&code)

SEE ALSO
Test::Builder provides the testing methods used in this module.

Test::Builder::Module is the superclass of this module.