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NAME

Test::CLI - Testing command-line invocations

VERSION

This document describes Test::CLI version 0.001.

Perl Version Current CPAN version Kwalitee CPAN Testers CPAN Testers Matrix

SYNOPSIS

use Test::CLI qw< tc >;

my $tc = tc(qw{ ls [options=-l] <dir> });

ok $tc->run('/'), 'plain run returns success/failure as boolean';

# run and test on one go
$tc->run_ok(dir => '/etc'); # run & test in one go
$tc->run_ok(dir => '/var', 'optional message');

# Last run is cached, all tests are related to it
$tc->stdout_like(qr{log});
$tc->stderr_is('');

# Tests can be chained
$tc->exit_code_is(0)
   ->signal_is(0)
   ->timeout_is(0)
   ->stdout_like(qr{run});

# Verbose mode produces a dump of the whole run result if the test
# is not successful
$tc->verbose(1);
$tc->failure_ok('test fails because run was ok'); # will dump data

# It's always possible to go more in depth anyway
$tc->run('/not-existent');
my $run = $tc->last_run; # Test::Command::Runner::Record object
isnt $run->exit_code, 0, 'file does not exist'
   or diag($run->stdout);

DESCRIPTION

Test::CLI helps with performing tests of invoking external commands, leveraging Command::Template::Runner for a flexible way of easily calling these commands and Command::Template::Runner::Record for analyzing the outcome of these commands.

In general, it is geared at covering simpler cases where there is no interaction with the command that is run, apart possibly providing a standard input for the command to read in. To this extent, then, it is mostly indicated for non-interactive commands (like, for example, most Unix commands, or most of the sub-commands of git).

INTERFACE

The interface is object-oriented, with the exception of the function "tc" (which is also aliased as "test_cli") that allows easily getting a new Test::CLI object.

Functions

There is one function with two aliases:

test_cli
tc
my $tc = test_cli(@command_template);

Create a Test::CLI object from the provided @command_template. It is actually a wrapper around the "new" class method.

Class Method: Constructor

The following constructor is supported as a class method:

new
my $tc = Test::CLI->new(@command_template);

The @command_template is parsed and used through Command::Template (actually, through Command::Template::Runner).

Returns a Test::CLI object, see below for the available interface of this object.

Methods: Accessors

The following accessors are supported:

last_run
my $r = $tc->last_run;

Returns the last Command::Template::Runner::Record produced in the last command run.

Read-only.

last_command
my $string = $tc->last_command;

Returns the stringification of the latest command that was run.

Read-only.

runner
my $runner = $tc->runner;

Returns the Command::Template::Runner object used by Test::CLI for executing commans.

Read-only.

verbose
my $is_verbose = $tc>verbose;
$tc->verbose(1); # set verbose mode
$tc->verbose(0); # unset verbose mode

Get or set the verbosity in error output. When set, each error in a test also generates a dump of the Command::Template::Runner::Record object via a diag call.

Defaults to false.

Returns the current value for the flag when called without parameters. Sets the value and returns the object reference otherwise.

Read-write method.

Method: Executing

The following method allows executing one run of the command template through Command::Template::Runner, although with a different return value.

run
my $run_was_successful = $tc->run(%bindings_and_options);

Run the command with the provided bindings and options (see Command::Template::Runner for the details).

The method returns a true value if the command execution is successful (i.e. the exit value is 0 and there was no signal terminating the command). It also records the last run overall result as a Command::Template::Runner::Record object that can be later retrieved via "last_run".

Method: Dumping

The following method is not a test but allows introspection. It is called automatically if a test is unsuccessful and "verbose" is true.

dump_diag

This method method allows dumping the outcome of the last run as a diag message (which goes to standard error).

The method returns a reference to the object itself, for easier chaining.

Methods: Testing

The central methods of this package are devoted to testing the outcome of a command execution.

All the following methods return the object's reference, so that multiple tests can be chained one after another.

Before describing the methods, it's useful to point out what characteristics are tested:

exit code

the command's exit code, typically provided by the command's exit function;

signal

a signal that might have forced the command's process to exit;

timeout

a timeout set when calling the command, which might have been hit (leading to termination of the command's process) or not;

stdout

what the command sends on the standard output;

stderr

what the command sends on the standard error;

merged

what the command sends on either output channels (standard error first, then standard output).

All test functions accept an optional last parameter to pass a custom message to mark the text; if not present or undefined, it is automatically generated based on the specific test and the command that has been expanded.

The following test functions are available:

run_ok
$tc->run_ok(\%bindings_and_opts);
$tc->run_ok(\%bindings_and_opts, $message);

First call "run" and then "ok" to do a new run with the provided parameters and then check that the run is successful.

run_failure_ok
$tc->run_failure_ok(\%bindings_and_opts);
$tc->run_failure_ok(\%bindings_and_opts, $message);

First call "run" and then "failure_ok" to do a new run with the provided parameters and then check that the run is NOT successful.

ok
$tc->ok;
$tc->ok('command successful');

Check if the latest run was successful. This is defined by "success" in Command::Template::Runner::Record, that checks that neither a signal nor a non-0 exit code were returned.

failure_ok
$tc->failure_ok;
$tc->failure_ok('command failed as expected');

Check if the latest run was unsuccessful (this is considered a condition to pass the test, i.e. the test passes if the command fails). This is defined by "failure" in Command::Template::Runner::Record, that checks that neither a signal nor a non-0 exit code were returned.

Other test functions are described in the following subsections.

Characteristic-specific successful tests

This type of test succeeds if the value corresponding to the specific characteristic is 0.

exit_code_ok
$tc->exit_code_ok;
$tc->exit_code_ok('exit code 0 as expected');
signal_ok
$tc->signal_ok;
$tc->signal_ok('signal 0 as expected');
in_time_ok
$tc->in_time_ok;
$tc->in_time_ok('timeout 0 as expected');

Characteristic-specific failure tests

This type of test succeeds if the value corresponding to the specific characteristic is different from 0.

exit_code_failure_ok
$tc->exit_code_failure_ok;
$tc->exit_code_failure_ok('exit code different from 0 as expected');
signal_failure_ok
$tc->signal_failure_ok;
$tc->signal_failure_ok('signal different from 0 as expected');
timed_out_ok
$tc->timed_out_ok;
$tc->timed_out_ok('timeout different from 0 as expected');

Characteristic-specific equality tests

This type of test succeeds is the value corresponding to the specific characteristic is as specified.

exit_code_is
$tc->exit_code_is(0);
$tc->exit_code_is(42, 'exit code is 42 as expected');
signal_is
$tc->signal_is(0);
$tc->signal_is(9, 'killed without appeal');
timeout_is
$tc->timeout_is(0);
$tc->timeout_is(5, 'timed out after 5 seconds');
stdout_is
$tc->stdout_is('foo bar baz');
$tc->stdout_is('foo bar baz', 'standard output as expected');
stderr_is
$tc->stderr_is('foo bar baz');
$tc->stderr_is('foo bar baz', 'standard error as expected');
merged_is
$tc->merged_is('foo bar baz');
$tc->merged_is('foo bar baz', 'merge of standard output and error as expected');

Characteristic-specific inequality tests

This type of test succeeds is the value corresponding to the specific characteristic is different from what specified.

exit_code_isnt
$tc->exit_code_isnt(0);
$tc->exit_code_isnt(42, 'exit code is 42 as expected');
signal_isnt
$tc->signal_isnt(0);
$tc->signal_isnt(9, 'not killed without appeal');
timeout_isnt
$tc->timeout_isnt(0);
$tc->timeout_isnt(5, 'timeout not 5 seconds');
stdout_isnt
$tc->stdout_isnt('foo bar baz');
$tc->stdout_isnt('foo bar baz', 'standard output different from it');
stderr_isnt
$tc->stderr_isnt('foo bar baz');
$tc->stderr_isnt('foo bar baz', 'standard error different from it');
merged_isnt
$tc->merged_isnt('foo bar baz');
$tc->merged_isnt('foo bar baz', 'merge of standard output and error...');

Characteristic-specific similarity (match) tests

This type of test succeeds is the value corresponding to the specific characteristic matches a regular expression.

stdout_like
$tc->stdout_like(qr{(^mxs: foo | bar | baz)});
$tc->stdout_like(qr{(^mxs: foo | bar | baz)}, 'standard output match');
stderr_like
$tc->stderr_like(qr{(^mxs: foo | bar | baz)});
$tc->stderr_like(qr{(^mxs: foo | bar | baz)}, 'standard error match');
merged_like
$tc->merged_like(qr{(^mxs: foo | bar | baz)});
$tc->merged_like(qr{(^mxs: foo | bar | baz)}, 'merged outputs match');

Characteristic-specific unsimilarity (negated match) tests

This type of test succeeds is the value corresponding to the specific characteristic does not match a regular expression.

stdout_unlike
$tc->stdout_unlike(qr{(^mxs: foo | bar | baz)});
$tc->stdout_unlike(qr{(^mxs: foo | bar | baz)}, 'standard output no match');
stderr_unlike
$tc->stderr_unlike(qr{(^mxs: foo | bar | baz)});
$tc->stderr_unlike(qr{(^mxs: foo | bar | baz)}, 'standard error no match');
merged_unlike
$tc->merged_unlike(qr{(^mxs: foo | bar | baz)});
$tc->merged_unlike(qr{(^mxs: foo | bar | baz)}, 'merged outputs no match');

BUGS AND LIMITATIONS

Minimul perl version 5.24.

Report bugs through GitHub (patches welcome) at https://github.com/polettix/Test-CLI.

AUTHOR

Flavio Poletti <flavio@polettix.it>

COPYRIGHT AND LICENSE

Copyright 2021 by Flavio Poletti <flavio@polettix.it>

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.