ExtUtils::ModuleMaker - Better than h2xs for creating modules


ExtUtils-ModuleMaker documentation Contained in the ExtUtils-ModuleMaker distribution.

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NAME

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ExtUtils::ModuleMaker - Better than h2xs for creating modules

SYNOPSIS

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At the command prompt:

    %   modulemaker

Inside a Perl program:

    use ExtUtils::ModuleMaker;

    $mod = ExtUtils::ModuleMaker->new(
        NAME => 'Sample::Module' 
    );

    $mod->complete_build();

    $mod->dump_keys(qw|
        ...  # key provided as argument to constructor
        ...  # same
    |);

    $mod->dump_keys_except(qw|
        ...  # key provided as argument to constructor
        ...  # same
    |);

    $license = $mod->get_license();

    $mod->make_selections_defaults();

VERSION

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This document references version 0.51 of ExtUtils::ModuleMaker, released to CPAN on February 9, 2008.

DESCRIPTION

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This module is a replacement for the most typical use of the h2xs utility bundled with all Perl distributions: the creation of the directories and files required for a pure-Perl module to be installable with make and distributable on the Comprehensive Perl Archive Network (CPAN).

h2xs has many options which are useful -- indeed, necessary -- for the creation of a properly structured distribution that includes C code as well as Perl code. Most of the time, however, h2xs is used as follows

    %   h2xs -AXn My::Module

to create a distribution containing only Perl code. ExtUtils::ModuleMaker is intended to be an easy-to-use replacement for this use of h2xs.

While you can call ExtUtils::ModuleMaker from within a Perl script (as in the SYNOPSIS above), it's easier to use with a command-prompt invocation of the modulemaker script bundled with this distribution:

    %   modulemaker

Then respond to the prompts. For Perl programmers, laziness is a virtue -- and modulemaker is far and away the laziest way to create a pure Perl distribution which meets all the requirements for worldwide distribution via CPAN.

USAGE

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Usage from the command-line with modulemaker

The easiest way to use ExtUtils::ModuleMaker is to invoke the modulemaker script from the command-line. You can control the content of the files built by modulemaker either by supplying command-line options or -- easier still -- replying to the screen prompts in modulemaker's interactive mode.

If you are encountering ExtUtils::ModuleMaker for the first time, you should turn now to the documentation for modulemaker which is bundled this distribution. Return to this document once you have become familiar with modulemaker.

Use of Public Methods within a Perl Program

You can use ExtUtils::ModuleMaker within a Perl script to generate the directories and files needed to begin work on a CPAN-ready Perl distribution. You will need to call new() and complete_build(), both of which are described in the next section. These two methods control the building of the file and directory structure for a new Perl distribution.

There are four other publicly available methods in this version of ExtUtils::ModuleMaker. dump_keys, dump_keys_except and get_license are intended primarily as shortcuts for trouble-shooting problems with an ExtUtils::ModuleMaker object. make_selections_defaults enables you to be even lazier in your use of ExtUtils::ModuleMaker by saving keystrokes entered for attributes.

new

Creates and returns an ExtUtils::ModuleMaker object. Takes a list containing key-value pairs with information specifying the structure and content of the new module(s). (In this documentation, we will sometimes refer to these key-value pairs as the attributes of the ExtUtils::ModuleMaker object.) With the exception of key EXTRA_MODULES (see below), the values in these pairs are all strings. Like most such lists of key-value pairs, this list is probably best held in a hash. Keys which may be specified are:

* Required Argument

* NAME

The only required feature. This is the name of the primary module (with '::' separators if needed). Will no longer support the older, Perl 4-style separator ''''' like the module D'Oh. There is no current default for NAME; you must supply a name explicitly.

* Other Important Arguments

* ABSTRACT

A short description of the module. CPAN likes to use this feature to describe the module. If the abstract contains an apostrophe ('), then the value corresponding to key ABSTRACT in the list passed to the constructor must be double-quoted; otherwise Makefile.PL gets messed up. Certain CPAN indexing features still work better if the abstract is 44 or fewer characters in length, but this does not appear to be as mandatory as in the past. (Defaults to dummy copy.)

* VERSION

A string holding the version number. For alpha releases, include an underscore to the right of the dot like 0.31_21. (Default is 0.01.)

* LICENSE

Which license to include in the Copyright section. You can choose one of the standard licenses by including 'perl', 'gpl', 'artistic', and 18 others approved by opensource.org. The default is to choose the 'perl' flavor which is to share it ''under the same terms as Perl itself.''

Other licenses can be added by individual module authors to ExtUtils::ModuleMaker::Licenses::Local to keep your company lawyers happy.

Some licenses include placeholders that will be replaced with AUTHOR information.

* BUILD_SYSTEM

This can take one of three values:

* 'ExtUtils::MakeMaker'

The first generates a basic Makefile.PL file for your module.

* 'Module::Build'

The second creates a Build.PL file.

* 'Module::Build and Proxy'

The third creates a Build.PL along with a proxy Makefile.PL script that attempts to install Module::Build if necessary, and then runs the Build.PL script. This option is recommended if you want to use Module::Build as your build system. See Module::Build::Compat for more details.

Note: To correct a discrepancy between the documentation and code in earlier versions of ExtUtils::ModuleMaker, we now explicitly provide this synonym for the third option:

    'Module::Build and proxy Makefile.PL'

(Thanks to David A Golden for spotting this bug.)

* COMPACT

For a module named ''Foo::Bar::Baz'' creates a base directory named ''Foo-Bar-Baz'' instead of Foo/Bar/Baz. (Default is off.)

* VERBOSE

Prints messages to STDOUT as it creates directories, writes files, etc. (Default is off.)

* PERMISSIONS

Used to create new directories. (Default is 0755: group and world can not write.)

* USAGE_MESSAGE

Message given when the module dies. Scripts should set this to the same string it would print if the user asked for help. (A reasonable default is provided.)

* NEED_POD

Include POD section in *.pm files created. (Default is on.)

* NEED_NEW_METHOD

Include a simple new() method in the *.pm files created. (Default is on.)

* CHANGES_IN_POD

Omit a Changes file, but instead add a HISTORY section to the POD. (Default is off).

* INCLUDE_MANIFEST_SKIP

Boolean value which, if true, includes a MANIFEST.SKIP file in the distribution with reasonable default values facilitating use of the make manifest command during module development. (Thanks to David A Golden for this feature. Default is off.)

* INCLUDE_TODO

Boolean value which, if true, includes a Todo file in the distribution in which the module's author or maintainer can discuss future lines of development. (Default is on.)

* INCLUDE_LICENSE

Boolean value which, if true, includes a LICENSE file in the distribution. (Which LICENSE file is determined in the LICENSE option.) (Default is on.)

* INCLUDE_SCRIPTS_DIRECTORY

Boolean value which, if true, includes a scripts/ directory (at the same level as lib/ or t/). (Default is on.)

* INCLUDE_WARNINGS

Boolean value which, if true, inserts use warnings; in all Perl modules created by use of this module. (Default is off.)

* INCLUDE_ID_LINE

Boolean value which, if true, inserts #$Id: ModuleMaker.pm 1153 2007-03-28 00:06:01Z jimk $ in all Perl modules created by use of this module for the purpose of inserting a Subversion file 'Id' string. (Default is off.)

* AUTHOR

Name of the author. If the author's name contains an apostrophe ('), then the corresponding value in the list passed to the constructor must be double-quoted; otherwise Makefile.PL gets messed up. (Defaults to dummy copy.)

* EMAIL

Email address of the author. If the author's e-mail address contains an apostrophe ('), then the corresponding value in the list passed to the constructor must be double-quoted; otherwise Makefile.PL gets messed up. (Defaults to dummy copy.)

* CPANID

The CPANID of the author. If this is omitted, then the line will not be added to the documentation. (Defaults to dummy copy.)

* WEBSITE

The personal or organizational website of the author. If this is omitted, then the line will not be added to the documentation. (Defaults to dummy copy.)

* ORGANIZATION

Company or group owning the module. If this is omitted, then the line will not be added to the documentation. (Defaults to dummy copy.)

* EXTRA_MODULES

A reference to an array of hashes, each of which contains values for additional modules in the distribution.

    $mod = ExtUtils::ModuleMaker->new( 
        NAME           => 'Alpha::Beta',
        EXTRA_MODULES  => [
            { NAME => 'Alpha::Beta::Gamma' },
            { NAME => 'Alpha::Beta::Delta' },
            { NAME => 'Alpha::Beta::Gamma::Epsilon' },
        ],
    );

As with the primary module, the only attribute required for each extra module is NAME. Other attributes may be supplied but the primary module's values will be used if no value is given here.

Each extra module will be created in the correct relative place in the lib directory. By default, a test file will also be created in the t directory corresponding to each extra module to test that it loads properly. (See EXTRA_MODULES_SINGLE_TEST_FILE below to learn how to change this behavior.) However, no other supporting documents (e.g., README, Changes) will be created.

This is one major improvement over the earlier h2xs as you can now build multi-module packages.

* FIRST_TEST_NUMBER

A non-negative natural number from which the count begins in test files that are numerically ordered. (Default is 1.)

* TEST_NUMBER_FORMAT

In test files that are numerically ordered, a Perl sprintf formatting string that specifies how FIRST_TEST_NUMBER is to be formatted. (Default is "%03d".)

* TEST_NAME

String forming the core of the name of a test file. (Default is load).

* TEST_NAME_DERIVED_FROM_MODULE_NAME

Boolean value which, when true, tells ExtUtils::ModuleMaker to create a file in the test suite with a name derived from the .pm package it is testing, thereby overriding any value set in the TEST_NAME attribute. For example, for a module called 'Alpha::Sigma::Tau', a test file named t/Alpha_Sigma_Tau.t will be created. (Default is off.)

* TEST_NAME_SEPARATOR

String holding the character which joins components of a test file's name, e.g., the character used to join 001 and <load> in a file named 001_load.t. (Defaults to an underscore _.)

* EXTRA_MODULES_SINGLE_TEST_FILE

Boolean value which, when true and when extra modules have been specified in the EXTRA_MODULES attribute, will put tests for those extra modules in a single test file rather than in individual test files corresponding to each module. (Default is off.)

* INCLUDE_POD_COVERAGE_TEST

Boolean value which, if true, causes a test file called t/pod-coverage.t to be included in the t/ directory. This test is advocated by some Perl quality assurance experts and module authors. However, since the maintainer of ExtUtils::ModuleMaker is not persuaded of its worth, default is off.

* INCLUDE_POD_TEST

Boolean value which, if true, causes a test file called t/pod.t to be included in the t/ directory. This test is advocated by some Perl quality assurance experts and module authors. However, since the maintainer of ExtUtils::ModuleMaker is not persuaded of its worth, default is off.

* INCLUDE_FILE_IN_PM

String holding a path to a file containing Perl code and/or documentation which will be included in each lib/*.pm file created in a particular distribution. By default, such content is placed after any constructor and before the main POD block. This could, for example, be used to insert stub subroutines in each package within a distribution. Default is off.

* Arguments for Advanced Usages

* INTERACTIVE

Activates interactive mode in modulemaker utility. The interactive mode presents the user with a series of menus from which the user selects features by entering text at the command prompt. This attribute should only be used by interactive scripts like modulemaker. (Default is off.)

* ALT_BUILD

Name of a Perl package holding methods which override those called withiin complete_build to shape the content of files created by using ExtUtils::ModuleMaker. See "An Alternative Approach to Subclassing" below.

complete_build

Creates all directories and files as configured by the key-value pairs passed to ExtUtils::ModuleMaker::new. Returns a true value if all specified files are created -- but this says nothing about whether those files have been created with the correct content.

dump_keys

When troubleshooting problems with an ExtUtils::ModuleMaker object, it is often useful to use Data::Dumper to dump the contents of the object. Use dump_keys() when you only need to examine a few of the object's attributes.

    $mod->dump_keys( qw| NAME ABSTRACT | );

dump_keys_except

When troubleshooting problems with an ExtUtils::ModuleMaker object, it is often useful to use Data::Dumper to dump the contents of the object. However, since certain elements of that object are often quite lengthy (e.g, the values of keys LicenseParts and USAGE_MESSAGE), it's handy to have a dumper function that dumps all keys except certain designated keys.

    $mod->dump_keys_except(qw| LicenseParts USAGE_MESSAGE |);

get_license

Returns a string which nicely formats a short version of the License and Copyright information.

    $license = $mod->get_license();
    print $license;

... will print something like this:

    =====================================================================
    =====================================================================
    [License Information]
    =====================================================================
    =====================================================================
    [Copyright Information]
    =====================================================================
    =====================================================================

(Earlier versions of ExtUtils::ModuleMaker contained a Display_License function in each of submodules ExtUtils::ModuleMaker::Licenses::Standard and ExtUtils::ModuleMaker::Licenses::Local. These functions were never publicly documented or tested. get_license() is intended as a replacement for those two functions.)

make_selections_defaults()

Saves the values you entered as arguments passed to new() in a personal defaults file so that they supersede the defaults provided by ExtUtils::ModuleMaker itself.

This is an advanced usage of ExtUtils::ModuleMaker. If you have used ExtUtils::ModuleMaker more than once, you have probably typed in a choice for AUTHOR, EMAIL, etc., more than once. To save unnecessary typing and reduce typing errors, ExtUtils::ModuleMaker now offers you the possibility of establishing personal default values which override the default values supplied with the distribution and found in lib/ExtUtils/ModuleMaker/Defaults.pm.

Suppose that you have called ExtUtils::ModuleMaker::new() as follows:

    $mod = ExtUtils::ModuleMaker->new(
        NAME            => 'Sample::Module',
        ABSTRACT        => 'Now is the time to join the party',
        AUTHOR          => 'Hilton Stallone',
        CPANID          => 'RAMBO',
        ORGANIZATION    => 'Parliamentary Pictures',
        WEBSITE         => 'http://parliamentarypictures.com',
        EMAIL           => 'hiltons@parliamentarypictures.com',
    );

While $mod is still in scope, you can call:

    $mod->make_selections_defaults()

and the values selected -- with two important exceptions -- will be saved in a Personal/Defaults.pm file stored in your home directory. The next time you invoke ExtUtils::ModuleMaker, the new values will appear in the appropriate locations in the files created by complete_build(). They will also appear in the menus provided on screen by the modulemaker utility.

What are those two important exceptions?

* NAME

You cannot enter a default value for NAME: the name of the module you are creating. ExtUtil::ModuleMaker's own defaults file omits a value for NAME to prevent you from overwriting an already existing module. (More precisely, the default value is an empty string. ExtUtil::ModuleMaker will throw an error if you attempt to create a module whose name is empty.) This precaution applies to your personal defaults file as well.

* ABSTRACT

Since every module you create presumably has its own unique purpose, every module must have a unique ABSTRACT to summarize that purpose. ExtUtil::ModuleMaker supplies the following string as the default value for the ABSTRACT key:

    Module abstract (<= 44 characters) goes here

... a string which, not coincidentally, happens to be exactly 44 characters long -- so you can just overstrike it. This will be the default value for ABSTRACT in any Personal/Defaults.pm file you create as well.

CUSTOMIZATION

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ExtUtils::ModuleMaker is designed to be customizable to your needs and to offer you more flexibility as you become more experienced with it.

Via modulemaker Utility Interactive Mode

As with everything else about ExtUtils::ModuleMaker, the easiest, laziest way to get started is via the modulemaker utility; see its documentation. Suppose that you have entered your correct name, email address and website at the prompts in modulemaker's Author Menu.

  ------------------------

  modulemaker: Author Menu

      Feature       Current Value
  N - Author        'John Q Public'
  C - CPAN ID       'MODAUTHOR'
  O - Organization  'XYZ Corp.'
  W - Website       'http://public.net/~jqpublic'
  E - Email         'jqpublic@public.net'

  R - Return to main menu
  X - Exit immediately

  Please choose which feature you would like to edit:

Why should you ever have to enter this information again? Return to the modulemaker Main Menu (R).

  ------------------------

  modulemaker: Main Menu

      Feature                     Current Value
  N - Name of module              ''
  S - Abstract                    'Module abstract (<= 44 characters) goes here'
  A - Author information
  L - License                     'perl'
  D - Directives
  B - Build system                'ExtUtils::MakeMaker'

  G - Generate module
  H - Generate module;
      save selections as defaults

  X - Exit immediately

  Please choose which feature you would like to edit: 

Select H instead of G to generate the distribution. An internal call to make_selections_defaults() will save those selections in a personal defaults file and present them to you on the Author Menu the next time you go to use it.

Via modulemaker Utility Command-Line Options Mode

For simplicity, not all of ExtUtils::ModuleMaker's default values are represented on modulemaker's menus. Those that are not represented on those menus cannot be changed from there. They can, however, in many cases be specified as options passed to modulemaker on the command-line and automatically saved as personal defaults by including the s flag as one of those options. If, for example, your name is 'John Q Public' and you want all modules you create to have compact top-level directories, you would call:

    %   modulemaker -Icsn Sample::Module -u 'John Q Public'

A distribution with a top-level directory Sample-Module would be created. 'John Q Public' would appear in appropriate places in Sample-Module/Makefile.PL and Sample-Module/lib/Sample/Module.pm. You could then throw away the entire Sample-Module directory tree. The next time you call modulemaker, the call

    %   modulemaker -In Second::Module

would suffice to generate a compact top-level directory and 'John Q Public' would appear in appropriate locations instead of the dreaded 'A. U. Thor'.

Via ExtUtils::ModuleMaker::new()

In all cases, ExtUtils::ModuleMaker's default values can be overridden with arguments passed to new() inside a Perl program. The overriding can then be made permanent by calling make_selections_defaults().

Suppose, for example,

1

that you want the files in your test suite to appear in a numerical order starting from 0 rather than ExtUtils::ModuleMaker's own default starting point of 1;

2

that you want the number in the test file's name to be formatted as a two-digit string padded with zeroes rather than ExtUtils::ModuleMaker's own default format of a three-digit, zero-padded string;

3

that you want the numerical part of the test filename to be joined to the lexical part with a dot (.) rather than ExtUtils::ModuleMaker's own default linkage character of an underscore (_); and

4

that you want the lexical part of the test filename to reflect the module's name rather than ExtUtils::ModuleMaker's default of load.

Your Perl program would look like this:

    #!/usr/local/bin/perl
    use strict;
    use warnings;
    use ExtUtils::ModuleMaker;

    my $mod = ExtUtils::ModuleMaker->new(
        NAME        => 'Sample::Module',
        AUTHOR      => 'John Q Public',
        COMPACT     => 1,
        FIRST_TEST_NUMBER    => 0,
        TEST_NUMBER_FORMAT   => "%02d",
        TEST_NAME_SEPARATOR  => q{.},
        TEST_NAME_DERIVED_FROM_MODULE_NAME => 1,
    );

    $mod->make_selections_defaults();

A subsequent call to the modulemaker utility,

    %    modulemaker -In Second::Balcony::Jump

would generate a directory tree with a compact top-level, 'John Q Public' in appropriate locations in Second-Balcony-Jump/Makefile.PL and Second-Balcony-Jump/lib/Second/Balcony/Jump.pm and a test file called Second-Balcony-Jump/t/00.Second.Balcony.Jump.t.

Via Subclassing ExtUtils::ModuleMaker

If you're a power-user, once you start playing with ExtUtils::ModuleMaker, you won't be able to stop. You'll ask yourself, ''Self, if I can change the default values, why can't I change the 'boilerplate' copy that appears inside the files which ExtUtils::ModuleMaker creates?''

Now, you can. You can hack on the methods which ExtUtils::ModuleMaker::new() and complete_build() call internally to customize their results to your heart's desire. The key: build an entirely new Perl extension whose lib/*.pm file has methods that override the methods you need overridden -- and only those methods. Follow these steps:

1. Study ExtUtils::ModuleMaker::Defaults, ::Initializers and ::StandardText

ExtUtils::ModuleMaker's default values are stored in lib/ExtUtils/ModuleMaker/Defaults.pm, specifically, in its default_values() method. Identify those values which you wish to change.

ExtUtils::ModuleMaker's other internal methods are found in two other files: /lib/ExtUtils/ModuleMaker/Initializers.pm and lib/ExtUtils/ModuleMaker/StandardText.pm. Rule of thumb: If an internal method is called within new(), it is found in ExtUtils::ModuleMaker::Initializers. If it is called within complete_build(), it is found in ExtUtils::ModuleMaker::StandardText. Study these two packages to identify the methods you wish to override.

Hint: If changing a default value in ExtUtils::ModuleMaker::Defaults will achieve your objective, make that change rather than trying to override methods in ExtUtils::ModuleMaker::Initializers or ExtUtils::ModuleMaker::StandardText.

Hint: You should probably think about overriding methods in ExtUtils::ModuleMaker::StandardText before overriding those in ExtUtils::ModuleMaker::Initializers.

2. Use modulemaker to Create the Framework for a New Distribution

You're creating a new Perl extension. Who ya gonna call? modulemaker, natch! (If you have not read the documentation for modulemaker by this point, do so now.)

Suppose that you've gotten on the 'Perl Best Practices' bandwagon and want to create all your Perl extensions in the style recommended by Damian Conway in the book of the same name. Use modulemaker to create the framework:

    %    modulemaker -Icqn ExtUtils::ModuleMaker::PBP \ 
         -u 'James E Keenan' \ 
         -p JKEENAN \
         -o 'Perl Seminar NY' \ 
         -w http://search.cpan.org/~jkeenan/

You used the -q option above because you do not want or need a constructor in the new package you are creating. That package will inherit its constructor from ExtUtils::ModuleMaker.

3. Edit the lib/*.pm File

Open up the best text-editor at your disposal and proceed to hack:

    %    vi ExtUtils-ModuleMaker-PBP/lib/ExtUtils/ModuleMaker/PBP.pm

Add this line near the top of the file:

    use base qw{ ExtUtils::ModuleMaker };

so that ExtUtils::ModuleMaker::PBP inherits from ExtUtils::ModuleMaker (which, in turn, inherits from ExtUtils::ModuleMaker::Defaults, ExtUtils::ModuleMaker::Initializers and ExtUtils::ModuleMaker::StandardText).

If you have carefully studied ExtUtils::ModuleMaker::Defaults, ExtUtils::ModuleMaker::StandardText and Perl Best Practices, you will write methods including the following:

    sub default_values {
        my $self = shift;
        my $defaults_ref = $self->SUPER::default_values();
        $defaults_ref->{COMPACT}                        = 1;
        $defaults_ref->{FIRST_TEST_NUMBER}              = 0;
        $defaults_ref->{TEST_NUMBER_FORMAT}             = "%02d";
        $defaults_ref->{EXTRA_MODULES_SINGLE_TEST_FILE} = 1;
        $defaults_ref->{TEST_NAME_SEPARATOR}            = q{.};
        $defaults_ref->{INCLUDE_TODO}                   = 0;
        $defaults_ref->{INCLUDE_POD_COVERAGE_TEST}      = 1;
        $defaults_ref->{INCLUDE_POD_TEST}               = 1;
        return $defaults_ref;;
    }

    sub text_Makefile {
        my $self = shift;
        my $Makefile_format = q~
    use strict;
    use warnings;
    use ExtUtils::MakeMaker;

    WriteMakefile(
        NAME            => '%s',
        AUTHOR          => '%s <%s>',
        VERSION_FROM    => '%s',
        ABSTRACT_FROM   => '%s',
        PL_FILES        => {},
        PREREQ_PM    => {
            'Test::More'    => 0,
            'version'       => 0,
        },
        dist            => { COMPRESS => 'gzip -9f', SUFFIX => 'gz', },
        clean           => { FILES => '%s-*' },
    );
    ~;
        my $text_of_Makefile = sprintf $Makefile_format,
            map { my $s = $_; $s =~ s{'}{\\'}g; $s; }
                $self->{NAME},
                $self->{AUTHOR},
                $self->{EMAIL},
                $self->{FILE},
                $self->{FILE},
                $self->{FILE};
        return $text_of_Makefile;
    }

Of course, for true Perl laziness, you'll use CPAN distribution ExtUtils::ModuleMaker::PBP, written by the author of ExtUtils::ModuleMaker as an exemplar of subclassing ExtUtils::ModuleMaker and generating the same output as Damian Conway's Module::Starter::PBP.

4. Test

How do you know you have correctly subclassed ExtUtils::ModuleMaker? With a test suite, of course. With careful editing, you can use many of ExtUtils::ModuleMaker's own tests in your new distribution. You will, of course, have to change a number of tests, because the default values implied by Conway's recommendations are different from ExtUtils::ModuleMaker's own defaults. Among other things, you will have to do a search-and-replace on all constructor calls.

    %    perl -pi'*.bak' -e 's{ExtUtils::ModuleMaker->new}{ExtUtils::ModuleMaker::PBP->new}g;'

Of course, you should have written your tests first, right?

5. Install and Use

You would install your new distribution as you would any other Perl distribution, i.e., with either ExtUtils::MakeMaker or Module::Build, depending on which you chose in creating your subclass.

    #!/usr/local/bin/perl
    use strict;
    use warnings;
    use ExtUtils::ModuleMaker::PBP;

    my $mod = ExtUtils::ModuleMaker::PBP->new(
        NAME        => 'Sample::Module',
    );

    $mod->complete_build();

For an adaptation of the modulemaker utility to work with ExtUtils::ModuleMaker::PBP, see mmkrpbp which is bundled with the latter package.

An Alternative Approach to Subclassing

There is one other way to subclass to ExtUtils::ModuleMaker which bears mentioning, more because the author used it in the development of this version of ExtUtils::ModuleMaker than because it is recommended. If for some reason you do not wish to create a full-fledged Perl distribution for your subclass, you can simply write the subclassing package and store it in the same directory hierarchy on your system in which your personal defaults file is stored.

For example, suppose you are experimenting and only wish to override one method in ExtUtils::ModuleMaker::StandardText. You can create a package called ExtUtils::ModuleMaker::AlternativeText. If you are working on a Unix-like system, you would move that file such that its path would be:

    "$ENV{HOME}/.modulemaker/ExtUtils/ModuleMaker/AlternativeText.pm"

You would then add one argument to your call to ExtUtils::ModuleMaker::new():

    my $mod = ExtUtils::ModuleMaker->new(
        NAME        => 'Sample::Module',
        ALT_BUILD   => 'ExtUtils::ModuleMaker::AlternativeText',
    );

CAVEATS

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* Tests Require Perl 5.6

While the maintainer has attempted to make the code in lib/ExtUtils/Modulemaker.pm and the modulemaker utility compatible with versions of Perl older than 5.6, the test suite currently requires 5.6 or later. The tests which require 5.6 or later are placed in SKIP blocks. Since the overwhelming majority of the tests do require 5.6, running the test suite on earlier Perl versions won't report much that is meaningful.

* Testing of modulemaker's Interactive Mode

The easiest, laziest and recommended way of using this distribution is the command-line utility modulemaker, especially its interactive mode. However, this is necessarily the most difficult test, as its testing would require capturing the STDIN, STDOUT and STDERR for a process spawned by a system('modulemaker') call from within a test file. For now, the maintainer has relied on repeated visual inspection of the screen prompts generated by modulemaker. With luck, Expect-based tests will be available in a future version.

* Testing modulemaker on Non-*nix-Like Operating Systems

Since testing the modulemaker utility from within the test suite requires a system() call, a clean test run depends in part on the way a given operating system parses command-line arguments. The maintainer has tested this on Darwin and Win32 and, thanks to a suggestion by A. Sinan Unur, solved a problem on Win32. Results on other operating systems may differ; feedback is welcome.

TO DO

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AUTHOR/MAINTAINER

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ExtUtils::ModuleMaker was originally written in 2001-02 by R. Geoffrey Avery (modulemaker [at] PlatypiVentures [dot] com). Since version 0.33 (July 2005) it has been maintained by James E. Keenan (jkeenan [at] cpan [dot] org).

SUPPORT

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Send email to jkeenan [at] cpan [dot] org. Please include 'modulemaker' in the subject line. Please report any bugs or feature requests to bug-ExtUtils-ModuleMaker@rt.cpan.org, or through the web interface at http://rt.cpan.org.

ACKNOWLEDGMENTS

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Thanks first and foremost to Geoff Avery for creating ExtUtils::Modulemaker and popularizing it via presentations I attended at YAPC::NA::2003 (Boca Raton) and YAPC::EU::2003 (Paris).

Soon after I took over maintenance of ExtUtils::ModuleMaker, David A Golden became a driving force in its ongoing development, providing suggestions for additional functionality as well as bug reports. David is the author of ExtUtils::ModuleMaker::TT which, while not a pure subclass of ExtUtils::ModuleMaker, extends its functionality for users of Template::Toolkit.

Thanks for suggestions about testing the modulemaker utility to Michael G Schwern on perl.qa and A Sinan Unur and Paul Lalli on comp.lang.perl.misc. Thanks for help in dealing with a nasty bug in the testing to Perlmonks davidrw and tlm. That well known Perl hacker, Anonymous Guest, contributed another bug report on rt.cpan.org.

As development proceeded, several issues were clarified by members of Perlmonks.org. CountZero, xdg, Tanktalus, holli, TheDamian and nothingmuch made particularly useful suggestions, as did Brian Clarkson.

Thanks also go to the following beta testers: Alex Gill, Marc Prewitt, Scott Godin, Reinhard Urban and imacat.

Version 0.39 of ExtUtils::ModuleMaker encountered spurious testing failure reports from testers.cpan.org. These were eventually diagnosed as being due to bugs in the automated testing programs and/or their operating environments on different systems -- i.e., to problems outside ExtUtils::ModuleMaker itself. Several Perlmonks helped investigate this problem: chromatic, dave_the_m, randyk, and njh.

Thanks to Paul M Sirianni for reporting bugs that led to versions 0.48 and 0.51.

COPYRIGHT

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DISCLAIMER OF WARRANTY

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BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE ''AS IS'' WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

SEE ALSO

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modulemaker, perlnewmod, h2xs, ExtUtils::MakeMaker, Module::Build, ExtUtils::ModuleMaker::PBP, ExtUtils::ModuleMaker::TT, mmkrpbp.


ExtUtils-ModuleMaker documentation Contained in the ExtUtils-ModuleMaker distribution.

package ExtUtils::ModuleMaker;
#$Id: ModuleMaker.pm 1153 2007-03-28 00:06:01Z jimk $
use strict;
local $^W = 1;
BEGIN {
    use vars qw( $VERSION @ISA );
    $VERSION = 0.51;
    use base qw(
        ExtUtils::ModuleMaker::Defaults
        ExtUtils::ModuleMaker::Initializers
        ExtUtils::ModuleMaker::StandardText
    );
};
use Carp;
use File::Path;
use File::Spec;
use Cwd;
use File::Save::Home qw(
    get_subhome_directory_status
    make_subhome_directory
);

#################### PUBLICLY CALLABLE METHODS ####################

sub new {
    my $class = shift;

    my $self = ref($class) ? bless( {}, ref($class) )
                           : bless( {}, $class );

    # multi-stage initialization of EU::MM object

    # 1.  Pull in arguments supplied to constructor -- but don't do anything
    # with them yet.  These will come from one of three sources:
    # a.  In a script:  KEY => 'Value' pairs supplied to new();
    # b.  From modulemaker command-line:  -option 'Value' pairs following
    # 'modulemaker';
    # c.  From modulemaker interactive mode:  hard-wired values which may
    # supersede (b) values.
    my @arglist = @_;
    croak "Must be hash or balanced list of key-value pairs: $!"
        if (@arglist % 2);
    my %supplied_params = @arglist;

    # 2. Determine if there already exists on system a directory capable of
    # holding user ExtUtils::ModuleMaker::Personal::Defaults.  The name of
    # such a directory and whether it exists at THIS point are stored in an
    # array, a reference to which is the return value of
    # _preexists_mmkr_directory and which is then stored in the object.
    # NOTE:  If the directory does not yet exists, it is NOT automatically
    # created.
    $self->{mmkr_dir_ref} =  get_subhome_directory_status(".modulemaker");
    {
        my $mmkr_dir = $self->{mmkr_dir_ref}->{abs};
        if (defined $self->{mmkr_dir_ref}->{flag}) {
            push @INC, $mmkr_dir;
        }
        my $pers_file = File::Spec->catfile( $mmkr_dir,
            qw| ExtUtils ModuleMaker Personal Defaults.pm |
        );
        if (-f $pers_file) {
            require ExtUtils::ModuleMaker::Personal::Defaults;
            unshift @ISA, qw(ExtUtils::ModuleMaker::Personal::Defaults);
        }
    }

    # 3.  Populate object with default values.  These values will come from
    # lib/ExtUtils/ModuleMaker/Defaults.pm, unless a Personal::Defaults file
    # has been located in step 1 above.
    my $defaults_ref;
    $defaults_ref = $self->default_values();
    foreach my $param ( keys %{$defaults_ref} ) {
        $self->{$param} = $defaults_ref->{$param};
    }


    # 4.  Process key-value pairs supplied as arguments to new() either
    # from user-written program or from modulemaker utility.
    # These override default values (or may provide additional elements).
    foreach my $param ( keys %supplied_params ) {
        $self->{$param} = $supplied_params{$param};
    }

    # 5.  Initialize keys set from information supplied above, system
    # info or EU::MM itself.
    $self->set_author_composite();
    $self->set_dates();
    $self->{eumm_version} = $VERSION;
    $self->{MANIFEST} = ['MANIFEST'];

    # 6.  Validate values supplied so far to weed out most likely errors
    $self->validate_values();

    # 7.  Initialize $self->{FILE} (done here because it presumes a validated
    # NAME, which was only done in step 6).  But allow exception for
    # Interactive mode because it throws a spurious warning.
    $self->set_file_composite() unless $self->{INTERACTIVE};

    # 8.  Initialize keys set from EU::MM::Licenses::Local or
    # EU::MM::Licenses::Standard
    $self->initialize_license();

    # 9.  Any EU::MM methods stored in ExtUtils::ModuleMaker::Standard Text
    # can be overriden by supplying a
    # value for ALT_BUILD (command-line option 'd') where the value is a Perl
    # module located in @INC
    if (defined $self->{ALT_BUILD}) {
        my $alt_build = $self->{ALT_BUILD};
        unless ($alt_build =~ m{^ExtUtils::ModuleMaker::}) {
            $alt_build = q{ExtUtils::ModuleMaker::} . $alt_build;
        }
        eval "require $alt_build";
        if ($@) {
            croak "Unable to locate $alt_build for alternative methods: $!";
        } else {
            unshift @ISA, $alt_build;
        };
    }
    return $self;
}

sub complete_build {
    my $self = shift;

    $self->create_base_directory();

    $self->create_directory( map { File::Spec->catdir( $self->{Base_Dir}, $_ ) }
        qw{ lib t } );                                      # always on

    $self->create_directory( map { File::Spec->catdir( $self->{Base_Dir}, $_ ) }
        qw{ scripts } )
            if $self->{INCLUDE_SCRIPTS_DIRECTORY};          # default is on

    $self->print_file( 'README',  $self->text_README() );   # always on

    $self->print_file( 'LICENSE', $self->{LicenseParts}{LICENSETEXT} )
        if $self->{INCLUDE_LICENSE};                        # default is on 

    $self->print_file( 'Todo',    $self->text_Todo() )
        if $self->{INCLUDE_TODO};                           # default is on

    $self->print_file( 'Changes', $self->text_Changes() )
        unless ( $self->{CHANGES_IN_POD} );                 # default is off

    $self->print_file( 'MANIFEST.SKIP',    
        $self->text_MANIFEST_SKIP() )
            if $self->{INCLUDE_MANIFEST_SKIP};              # default is off

    $self->print_file( qq|t/pod-coverage.t|, $self->text_pod_coverage_test() )
            if $self->{INCLUDE_POD_COVERAGE_TEST};          # default is off
            
    $self->print_file( qq|t/pod.t|, $self->text_pod_test() )
            if $self->{INCLUDE_POD_TEST};                   # default is off

    if ( $self->{BUILD_SYSTEM} eq 'ExtUtils::MakeMaker' ) {
        $self->print_file( 'Makefile.PL', $self->text_Makefile() );
    }
    else {
        $self->print_file( 'Build.PL', $self->text_Buildfile() );
        if ( $self->{BUILD_SYSTEM} eq 'Module::Build and proxy Makefile.PL' 
         or  $self->{BUILD_SYSTEM} eq 'Module::Build and Proxy') {
            $self->print_file( 'Makefile.PL',
                $self->text_proxy_makefile() );
        }
    }

    my @pmfiles = ( $self );
    foreach my $f ( @{ $self->{EXTRA_MODULES} } ) {
        push @pmfiles, $f;
    }
    foreach my $module ( @pmfiles ) {
        my ($dir, $file) = _get_dir_and_file($module);
        $self->create_directory( join( '/',  $self->{Base_Dir}, $dir ) );
        my $text_of_pm_file = $self->text_pm_file($module);
        $self->print_file( join( '/', $dir, $file ), $text_of_pm_file );
    }

    # How test files are created depends on how tests for EXTRA_MODULES
    # are handled: 1 test file per extra module (default) or all tests for all 
    # modules in a single file (example:  PBP).
    unless ($self->{EXTRA_MODULES_SINGLE_TEST_FILE}) {
        my $ct = $self->{FIRST_TEST_NUMBER};
        foreach my $module ( @pmfiles ) {
            my ($teststart, $testmiddle);
            
            # Are we going to include a number at start of test name?
            # (default)  If so, what is sprintf format and what character is
            # used to separate it from the lexical part of the test name?
            if (defined $self->{TEST_NUMBER_FORMAT}) {
                $teststart = "t/" . $self->{TEST_NUMBER_FORMAT} .
                    $self->{TEST_NAME_SEPARATOR};
            } else {
                $teststart = "t/";
            }

            # Are we going to derive the lexical part of the test name from
            # the name of the module it is testing?  (non-default)
            # Or are we simply going to use our pre-defined test name?
            # (default)
            if ($self->{TEST_NAME_DERIVED_FROM_MODULE_NAME}) {
                $testmiddle = $self->process_attribute( $module, 'NAME' );
                $testmiddle =~ s|::|$self->{TEST_NAME_SEPARATOR}|g;
            } else {
                $testmiddle = $self->{TEST_NAME};
            }
            my $testfilename = sprintf( $teststart . $testmiddle . q{.t}, $ct );
            $self->print_file( $testfilename,
                $self->text_test( $testfilename, $module ) );
            $ct++;
        }
    } else {
        my $teststart;
        if (defined $self->{TEST_NUMBER_FORMAT}) {
            $teststart = "t/" . $self->{TEST_NUMBER_FORMAT} .
                $self->{TEST_NAME_SEPARATOR};
        } else {
            $teststart = "t/";
        }
        my $testfilename = sprintf( $teststart . $self->{TEST_NAME} . q{.t}, 
            $self->{FIRST_TEST_NUMBER});
        $self->print_file( $testfilename,
            $self->text_test_multi( $testfilename, \@pmfiles ) );
    }

    $self->print_file( 'MANIFEST', join( "\n", @{ $self->{MANIFEST} } ) );
    $self->make_selections_defaults() if $self->{SAVE_AS_DEFAULTS};
    return 1;
}

sub dump_keys {
    my $self = shift;
    my %keys_to_be_shown = map {$_, 1} @_;
    require Data::Dumper;
    my ($k, $v, %retry);
    while ( ($k, $v) = each %{$self} ) {
        $retry{$k} = $v if $keys_to_be_shown{$k};
    }
    my $d = Data::Dumper->new( [\%retry] );
    return $d->Dump;
}

sub dump_keys_except {
    my $self = shift;
    my %keys_not_shown = map {$_, 1} @_;
    require Data::Dumper;
    my ($k, $v, %retry);
    while ( ($k, $v) = each %{$self} ) {
        $retry{$k} = $v unless $keys_not_shown{$k};
    }
    my $d = Data::Dumper->new( [\%retry] );
    return $d->Dump;
}

sub get_license {
    my $self = shift;
    return (join ("\n\n",
        "=====================================================================",
        "=====================================================================",
        $self->{LicenseParts}{LICENSETEXT},
        "=====================================================================",
        "=====================================================================",
        $self->{LicenseParts}{COPYRIGHT},
        "=====================================================================",
        "=====================================================================",
    ));
}

sub make_selections_defaults {
    my $self = shift;
    my %selections = %{$self};
    my @dv = keys %{ $self->default_values() };
    my $topfile = <<'END_TOPFILE';
package ExtUtils::ModuleMaker::Personal::Defaults;
use strict;

my %default_values = (
END_TOPFILE

    my @keys_needed;
    for my $k (@dv) {
        push @keys_needed, $k
            unless (
                $k eq 'ABSTRACT'         or 
                $k eq 'SAVE_AS_DEFAULTS'
            );
    }

    my $kvpairs;
    foreach my $k (@keys_needed) {
        $kvpairs .=
            (' ' x 8) . 
            (sprintf '%-16s', $k) . 
            '=> q{' . 
            $selections{$k} .  
            "},\n";
    }
    $kvpairs .= 
        (' ' x 8) . 
        (sprintf '%-16s', 'ABSTRACT') . 
        '=> q{Module abstract (<= 44 characters) goes here}' . 
        "\n";

    my $bottomfile = <<'END_BOTTOMFILE';
);

sub default_values {
    my $self = shift;
    return { %default_values };
}

1;

END_BOTTOMFILE

    my $output =  $topfile . $kvpairs . $bottomfile;

    my $mmkr_dir = make_subhome_directory($self->{mmkr_dir_ref});
    my $full_dir = File::Spec->catdir($mmkr_dir,
        qw| ExtUtils ModuleMaker Personal |
    );
    if (! -d $full_dir) {
        mkpath( $full_dir );
        if ($@) {
            croak "Unable to make directory for placement of personal defaults file: $!"; };
    }
    my $pers_full = File::Spec->catfile( $full_dir, q{Defaults.pm} );
    if (-f $pers_full ) {
        my $modtime = (stat($pers_full))[9];
        rename $pers_full,
               "$pers_full.$modtime"
            or croak "Unable to rename $pers_full: $!";
    }
    open my $fh, '>', $pers_full 
        or croak "Unable to open $pers_full for writing: $!";
    print $fh $output or croak "Unable to print $pers_full: $!";
    close $fh or croak "Unable to close $pers_full after writing: $!";
}

## C<_get_dir_and_file()>
## 
## This subroutine was originally in lib/ExtUtils/ModuleMaker/Utility.pm.  
## As other subroutines therein were superseded by calls to File::Save::Home
## functions, they were no longer called in the .pm or .t files, hence, became
## superfluous and uncovered by test suite.  When _get_dir_and_file() became the
## last called subroutine from Utility.pm, I decided it was simpler to pull it
## into the current package.
## 
## Usage     : _get_dir_and_file($module) within complete_build()
## Purpose   : Get directory and name for .pm file being processed
## Returns   : 2-element list: First $dir; Second: $file
## Argument  : $module: pointer to the module being built
##             (as there can be more than one module built by EU::MM);
##             for the primary module it is a pointer to $self
## Comment   : Merely a utility subroutine to refactor code; not a method call.

sub _get_dir_and_file {
    my $module = shift;
    my @layers      = split( /::/, $module->{NAME} );
    my $file        = pop(@layers) . '.pm';
    my $dir         = join( '/', 'lib', @layers );
    return ($dir, $file);
}

1;

#################### DOCUMENTATION ####################