Merge branch 'nop-type' into 'master'

New type: __nop

See merge request ungleich-public/cdist!996

cdist/conf/type/__nop/man.rst

@@ -0,0 +1,60 @@
+cdist-type__nop(7)
+==================
+
+NAME
+----
+cdist-type__nop - Do nothing, but allow dependencies to be specified.
+
+
+DESCRIPTION
+-----------
+If one has a type without any logic in the ``manifest`` (i.e. only some ``gencode-*`` logic), that depends on some other type, there are two ways make sure the dependencies taken into consideration:
+
+- Either remember to specify them "externally" *every time*, wherever and whenever those types are used
+- Include a ``manifest`` in the *dependent* type, that does something useless (or even nothing)
+
+This type provides a convenient solution for the latter one. It is guaranteed to have no effect on the target host, but it provides an 'anchor point' for type-writers to include in an otherwise empty ``manifest``.
+
+PARAMETERS
+----------
+None.
+
+The ``$__object_id`` is required though, so the type can be used several times.
+
+
+EXAMPLES
+--------
+
+Let's assume type ``__eggs`` depends on type ``__spam``, but has nothing in it's ``manifest``. In the simplest case, it's manifest can contain this:
+
+.. code-block:: sh
+    __spam
+
+If, ``__spam`` has parameters, however, one would resort to this at the place of use:
+
+.. code-block:: sh
+    __spam --foo bar
+    require="__spam" __ham --baz
+
+Or by using the ``__nop`` type, simply do away with the ``require``, and update ``__ham/manifest`` to specify the dependency:
+
+.. code-block:: sh
+    require="__spam" __nop $__object_id
+
+In this case, when the type is used, the depencency is automatic, and one could simply write:
+
+.. code-block:: sh
+    __spam --foo bar
+    __ham --baz
+
+AUTHORS
+-------
+Daniel Fancsali <fancsali@gmail.com>
+
+
+COPYING
+-------
+Copyright \(C) 2021 Daniel Fancsali. You can redistribute it
+and/or modify it under the terms of the GNU General Public License as
+published by the Free Software Foundation, either version 3 of the
+License, or (at your option) any later version.