Contributing
************

Thank you for considering contributing to Modules!


Support questions
=================

Please use the modules-interest mailing list for questions. Do not use
the issue tracker for this.


Asking for new features
=======================

Please submit your new feature wishes first to the modules-interest
mailing list. Discussion will help to clarify your needs and sometimes
the wanted feature may already be available.


Reporting issues
================

* Describe what you expected to happen.

* If possible, include a minimal, complete, and verifiable example to
  help us identify the issue.

* Describe what actually happened. Run the "module" command in "--
  debug" mode and include all the debug output obtained in your
  report.

* Provide the current configuration and state of your Modules
  installation by running the "module config --dump-state" command.

* Provide the name and content of the modulefiles you try to
  manipulate.


Submitting patches
==================

* Whether your patch is supposed to solve a bug or add a new feature,
  please include tests. In case of a bug, explain clearly under which
  circumstances it happens and make sure the test fails without your
  patch.

* If you are not yet familiar with the "git" command and GitHub,
  please read the don't be afraid to commit tutorial.


Start coding
------------

* Create a branch to identify the issue or feature you would like to
  work on

* Using your favorite editor, make your changes, committing as you go.

* Comply to the coding conventions of this project.

* Your Tcl code has to be compatible with Tcl version 8.5 and above
  (see Tcl 8.5 commands reference)

* Include tests that cover any code changes you make. Make sure the
  test fails without your patch.

* Run the tests and verify coverage.

* Push your commits to GitHub and create a pull request.


Design notes
------------

See the Design notes for recent feature specifications. You may also
find there some development howtos:

* Add new module sub-command

* Add new configuration option


Running the tests
-----------------

Run the basic test suite with:

   make test

This only runs the tests for the current environment. GitHub Actions
and Cirrus CI will run the full suite when you submit your pull
request.

There are more than 17 000 test cases thus it generally takes around
12 minutes to run the full test suite. It can be executed in *quick*
mode to just run the most essential tests in about 1 minute:

   make test QUICKTEST=y

The **script/mt** utility is also available to just execute one or
several testfiles. If a test fails, **script/mt** reports the *diff*
comparison between expected and actual results. For instance, to only
execute "testsuite/modules.50-cmds/470-variant.exp" testfile, run:

   script/mt 50/470

Run **script/mt** with "--help" option to get usage details and syntax
to select several testfiles.


Running test coverage
---------------------

Generating a report of lines that do not have test coverage can
indicate where to start contributing or what your tests should cover
for the code changes you submit.

Run "make test COVERAGE=y" which will automatically setup the Nagelfar
Tcl code coverage tool in your "modules" development directory and
instrument the source Tcl scripts. Then the full testsuite will be run
in coverage mode and an annotated script will be produced for each Tcl
script in "tcl" source directory ("tcl/*.tcl_m"):

   make test COVERAGE=y
   # then open tcl/*.tcl_m files and look for ';# Not covered' lines

The **script/mt** utility may also be used to run the test suite in
coverage mode on full testsuite or on a few testfiles:

   script/mt cov 70/{280,290}


Running linter tests
--------------------

Linter tools check code syntax and report issues and good practices to
follow. Modules uses Nagelfar to check syntax of Tcl scripts and
ShellCheck to lint sh, bash and ksh scripts.

Run "make testlint" to lint all sh, bash, ksh and Tcl scripts in your
local Modules repository.

The **script/mt** utility may also be used to run the full *lint* test
suite or just specific testfiles. For instance to only lint Tcl
scripts:

   script/mt lint 00/030


Check performances
------------------

The **script/mb** utility checks from your local repository the
performances of major releases of Modules and current branch. Current
ongoing modifications are first stashed, then **modulecmd.tcl** of the
releases and current branch are built. Different tests are run against
each version and the execution time of each test is reported in
millisecond:

   $ script/mb
             |   v4.1.4 |   v4.3.1 |   v4.5.3 |   v4.7.1 |   v5.1.1 |     main |
   ----------+----------+----------+----------+----------+----------+----------+
        help |        9 |       12 |       12 |       15 |       16 |       16 |
       avail |       61 |       67 |       76 |       82 |       91 |       86 |
      avail2 |       11 |       16 |       19 |       21 |       23 |       23 |
      avail3 |        - |        - |        - |      120 |      128 |      130 |
      whatis |      208 |      155 |      233 |      216 |      221 |      224 |
     whatis2 |       10 |       15 |       17 |       20 |       21 |       22 |
     whatis3 |        - |        - |        - |      287 |      307 |      314 |
     apropos |      208 |      153 |      222 |      210 |      220 |      223 |
        load |       66 |       87 |      134 |      162 |      120 |      126 |
        list |       24 |       23 |       33 |       22 |       25 |       25 |
      unload |       46 |       24 |       25 |       29 |       31 |       31 |

It helps to verify that current work committed in local repository
does not impact performances on simple test scenarios. Run
**script/mb** with "--help" option to get its usage details.

The "profile" mode may also be interesting to learn what are the
internal procedures of **modulecmd.tcl** taking most of the execution
time for each test:

   script/mb profile


Building the docs
-----------------

Build the docs in the "doc" directory using Sphinx:

   cd doc
   make html

Open "_build/html/index.html" in your browser to view the docs.

Read more about Sphinx.


Coding conventions
------------------

* Maximum line length is 78 characters

* Use 3 spaces to indent code (do not use tab character)

* Adopt Tcl minimal escaping style

* Procedure names: "lowerCameCase"

* Variable names: "nocaseatall"

* Curly brace and square bracket placement:

     if {![isStateDefined already_report]} {
        setState already_report 1
     }

* No trailing space nor misspelling


Commit hooks
------------

A **pre-commit** hook script is provided in the "script" directory of
the project to help you check that the contribution made is free of
misspellings and trailing spaces. It requires the codespell utility
that checks for typos in any kind of files and the Aspell utility that
spell checks documentation files. The **pre-commit** could be enabled
in your local repository with following command:

   ln -s ../../script/pre-commit .git/hooks/pre-commit

A **commit-msg** hook script is also provided in the "script"
directory of the project to help you check that your commit messages
are free of misspellings. It requires the Aspell utility and could be
enabled in your local repository with following command:

   ln -s ../../script/commit-msg .git/hooks/commit-msg


Emacs settings for coding conventions
-------------------------------------

This is an example Emacs configuration that adheres to the first two
coding conventions.  You may wish to add this to your ".emacs" or
".emacs.d/" to modify your tcl-mode:

   (add-hook 'tcl-mode-hook
      (lambda ()
        (setq indent-tabs-mode nil)
        (setq tcl-indent-level 3)
        (setq tcl-continued-indent-level 3)
        (font-lock-add-keywords nil '(("^[^\n]\\{79\\}\\(.*\\)$" 1
                                       font-lock-warning-face prepend)))))


Submitting installation recipes
===============================

* If you want to share your installation tips and tricks, efficient
  ways you have to write or organize your modulefiles or some
  extension you made to the "module" command please add a recipe to
  the cookbook section of the documentation.

* Create a directory under "doc/example" and put there the extension
  code or example modulefiles your recipe is about.

* Describe this recipe through a reStructuredText document in
  "doc/source/cookbook". It is suggested to have an *Implementation*,
  an *Installation* and an *Usage example* sections in that document
  to get as much as possible the same document layout across recipes.

* Submit a patch with all the above content.
