9
1
mirror of https://github.com/QuantumPackage/qp2.git synced 2024-11-18 19:32:20 +01:00
qp2/docs/source/programmers_guide/conventions.rst

116 lines
3.1 KiB
ReStructuredText

==================
Coding conventions
==================
General conventions
===================
All executable files should have a name with lowercase.
Tabs are forbidden everywhere.
Try to set the maximum line length to 80 characters. Long lines can be
automatically reformatted in vim by pressing :kbd:`gqj`.
Use blank lines between blocks to improve readability.
For existing files, stay faithful to the existing indentation.
Shell scripts
=============
Executables should have no extension. To know if the file is binary, or in
what shell scripting language it was written, the :command:`file` command can
be used. In addition, all the shell scripts should be under
:file:`${QP_ROOT}/scripts/`.
The exit code of the script should be 0 upon success only.
Bash and Python2 are the only shell scripting language permitted for
executables.
Bash
----
* Bash scripts should start with ``#!/bin/bash``
* All error messages should go to standard error, and should be prefixed with
the name of the command. For example, in Bash use
.. code:: bash
function echo_err() {
2>& echo $(basename $0)": error"
}
* The command-line options should be handled with ``getopt``.
* The script should check that the command-line arguments are consistent.
* Long options should be preferred to short options.
* Always quote strings containing variables, command substitutions, spaces or
shell meta characters, unless careful unquoted expansion is required.
* Use ``"$@"`` unless you have a specific reason to use ``$*``.
* Use ``$(command)`` instead of backticks, because they can be easily nested.
* ``[[ ... ]]`` is preferred over ``[``, ``test`` and ``/usr/bin/[``.
* Declare function-specific variables with local. Declaration and assignment
should be on different lines.
* Pipelines should be split one per line if they don't all fit on one line.
* Put ``; do`` and ``; then`` on the same line as the ``while``, ``for`` or ``if``.
Python
------
Only Python2 is supported. The reason is that some dependencies use Python2,
and we do not want yet to add an extra dependency to Python3.
Python scripts should start with ``#!/usr/bin/env python2`` to mention
explicitly that Python2 has to be used.
:command:`pylint` should be used to increase the quality of the source code.
IRPF90
======
The code can be automatically indented with :command:`irp_indent`.
Lines sould not be longer than 80 characters.
Mathematical formulas in the `BEGIN_DOC...END_DOC` sections sould be written in
LaTeX format, between `$` symbols.
All the providers, subroutines and functions should have a
`BEGIN_DOC...END_DOC` block.
Providers should never be present in the same file as a main program.
String must not use double quotes (`"`) but single quotes (`'`).
After a `read` statement there should be no comma.
Only standard Fortran is allowed : Intel or GNU extensions are forbidden.
The name of a program should be the same as the name of the file. For example,
for the :ref:`fci` program, we have
.. code-block:: fortran
program fci
and the file is named :file:`fci.irp.f`.