doc: desc. haveDynamicMPATH modulefile command

Signed-off-by: Xavier Delaruelle <xavier.delaruelle@cea.fr>

NEWS.rst

@@ -151,6 +151,7 @@ Modules 5.6.0 (not yet released)
 * Add :subcmd:`disable` sub-command, an alias of :subcmd:`saverm`
 * Add :subcmd:`describe` sub-command, an alias of :subcmd:`saveshow`
 * Add ``--show_hidden`` option, an alias of :option:`--all`
+* Add :mfcmd:`haveDynamicMPATH` modulefile command
 
 .. _Security policy: https://github.com/envmodules/modules/blob/main/SECURITY.md
 .. _Modules chat room: https://matrix.to/#/#modules:matrix.org

doc/source/changes.rst

@@ -1092,7 +1092,7 @@ The following modulefile Tcl commands appeared on Modules 5.
 |            | :mfcmd:`lsb-release`                                            |
 +------------+-----------------------------------------------------------------+
 | 5.6        | :mfcmd:`depends-on-any`, :mfcmd:`module-help`,                  |
-|            | :mfcmd:`module-warn`                                            |
+|            | :mfcmd:`module-warn`, :mfcmd:`haveDynamicMPATH`                 |
 +------------+-----------------------------------------------------------------+
 
 :mfcmd:`system`, :mfcmd:`is-used`

doc/source/modulefile.rst

@@ -351,6 +351,21 @@ the *modulefile* is being loaded.
        Option ``--return-value`` added.
 
 
+.. mfcmd:: haveDynamicMPATH
+
+ :mfcmd:`haveDynamicMPATH` command signals that a modulefile modifies the
+ :envvar:`MODULEPATH` environment variable. It is useful when the modulefile
+ conditionally updates :envvar:`MODULEPATH` and is processed by Lmod tool.
+
+ Here in the Modules tool, this command is implemented as a *no-operation*,
+ since the :subcmd:`spider` sub-command evaluates the modulefile in the
+ context of the current user to determine whether :envvar:`MODULEPATH` is
+ updated.
+
+ .. only:: html
+
+    .. versionadded:: 5.6
+
 .. mfcmd:: hide-modulefile modulefile
 
  Alias of :mfcmd:`module-hide` command.
@@ -2195,6 +2210,13 @@ The ``remove-property`` and ``extensions`` modulefile commands are evaluated
 as a *no-operation* command. No error is obtained if these commands are used
 in modulefiles but no change occurs.
 
+The :mfcmd:`haveDynamicMPATH` is evaluated as a *no-operation* modulefile
+command. If modulefile conditionally updates :envvar:`MODULEPATH` environment
+variable, this command is needed to help Lmod know that modulefile changes
+:envvar:`MODULEPATH`. :subcmd:`spider` sub-command on Modules does not need
+this information as modulefile is evaluated in the context of the current
+user to determine whether :envvar:`MODULEPATH` is updated.
+
 The :mfcmd:`break` command does not accept any argument. A ``msg`` argument
 can be set on Lmod to provide a customized break error message.
 
@@ -2256,7 +2278,8 @@ the dependent module will get automatically reloaded.
    .. versionadded:: 5.1
 
    .. versionchanged:: 5.6
-      Modulefile command :mfcmd:`add-property` implemented
+      Modulefile commands :mfcmd:`add-property` and :mfcmd:`haveDynamicMPATH`
+      implemented
 
 .. _Shell support:
 

doc/source/other-implementations.rst

@@ -114,7 +114,7 @@ the end of this section to map these equivalents.
 
    * - Lmod 8.8
      - Modules 5.6
-   * - ``extensions``, ``haveDynamicMPATH``, ``remove-property``
+   * - ``extensions``, ``remove-property``
      - :mfcmd:`getvariant`, :mfcmd:`is-saved`, :mfcmd:`is-used`,
        :mfcmd:`lsb-release`, :mfcmd:`module-help`, :mfcmd:`module-tag`,
        :mfcmd:`module-virtual`, :mfcmd:`module-warn`,