Help: Add `.. versionadded` directives to commands documentation

This change ony concerns directives that appear in the document body.

The guidelines for inserting version directives:

 * Baseline version is CMake 3.0, i.e. directives start at 3.1.
 * Always use `.. versionadded::` directive, avoid ad-hoc version
   references. Exception: policy pages.
 * For new command signatures, put `versionadded` on a separate line
   after the signature.
 * For a group of new signatures in a new document section,
   a single version note at the beginning of the section is sufficient.
 * For new options, put `versionadded` on a separate line before
   option description.
 * If all the option descriptions in the list are short one-liners,
   it's fine to put `versionadded` on the same line as the description.
 * If multiple option descriptions in close proximity would have
   the same ..versionadded directive, consider adding a single
   directive after the list, mentioning all added options.
 * For compact value lists and sub-option lists, put a single
  `versionadded` directive after the list mentioning all additions.
 * When a change is described in a single paragraph, put
   `versionadded` into that paragraph.
 * When only part of the paragraph has changed, separate the changed
   part if it doesn't break the flow. Otherwise, write a follow-up
   clarification paragraph and apply version directive to that.
 * When multiple version directives are close by, order earlier
   additions before later additions.
 * Indent related lists and code blocks to include them in the scope
   of `versionadded` directive.

Issue: #19715

1 files changed, 3 insertions, 0 deletions

diff --git a/Help/command/cmake_policy.rst b/Help/command/cmake_policy.rst
index 4bc7807..94060d9 100644
--- a/Help/command/cmake_policy.rst
+++ b/Help/command/cmake_policy.rst
@@ -28,6 +28,9 @@ encourage projects to set policies based on CMake versions:
 
   cmake_policy(VERSION <min>[...<max>])
 
+.. versionadded:: 3.12
+  The optional ``<max>`` version.
+
 ``<min>`` and the optional ``<max>`` are each CMake versions of the form
 ``major.minor[.patch[.tweak]]``, and the ``...`` is literal.  The ``<min>``
 version must be at least ``2.4`` and at most the running version of CMake.