[commands] New conan require (#4354)

* Add conan-require-command reference

* wip

* wip

* wip

Author: franramirez688

reference/commands.rst

@@ -31,6 +31,7 @@ and these :ref:`custom command examples <examples_extensions_custom_commands>`
    commands/version
    commands/workspace
    commands/run
+   commands/require
 
 - :doc:`conan cache <commands/cache>`: Return the path of recipes and packages in the cache
 - :doc:`conan config <commands/config>`: Manage Conan configuration (remotes, settings, plugins, etc)
@@ -47,6 +48,7 @@ and these :ref:`custom command examples <examples_extensions_custom_commands>`
 - :doc:`conan version <commands/version>`: Give information about the Conan client version
 - :doc:`conan workspace (incubating) <commands/workspace>`: Manage Conan workspaces
 - :doc:`conan run <commands/run>`: Execute binaries with automatic environment activation
+- :doc:`conan require <commands/require>`: Adds/removes requirements to/from your local conanfile
 
 
 **Creator commands:**

reference/commands/require.rst

@@ -0,0 +1,113 @@
+.. _reference_commands_require:
+
+conan require
+=============
+
+.. include:: ../../common/experimental_warning.inc
+
+.. autocommand::
+    :command: conan require -h
+
+
+The :command:`conan require` command helps to add any requirement as a version range or remove it from your *conanfile.py*. 
+
+
+.. important::
+
+    This command is only a UX utility. It's not aimed at replacing editing the conanfile, and it's not expected to cover
+    all the use cases, i.e., conditional requirements, requirements with different traits, etc. For all those mentioned
+    scenarios, we recommend editing the conanfile.py as usual.
+
+
+conan require add
+-----------------
+
+.. autocommand::
+    :command: conan require add -h
+
+Add a new requirement to your local *conanfile.py* as a version range.
+
+By default, it looks for the recipe name in any of your remotes. When a remote contains any result for the recipe
+required, the latest version is used and written as a version range between the version found and the next major one
+(if possible, as versions based on commits do not have that major version):
+
+.. code-block:: bash
+
+    $ conan require add fmt
+    Connecting to remote 'conancenter' anonymously
+    Found 21 pkg/version recipes matching fmt/* in conancenter
+    Added 'fmt/[>=12.1.0 <13]' as a new requires.
+
+It admits several arguments as new requirements:
+
+.. code-block:: bash
+
+    $ conan require add fmt zlib
+    Connecting to remote 'conancenter' anonymously
+    Found 21 pkg/version recipes matching fmt/* in conancenter
+    Found 5 pkg/version recipes matching zlib/* in conancenter
+    Added 'fmt/[>=12.1.0 <13]' as a new requires.
+    Added 'zlib/[>=1.3.1 <2]' as a new requires.
+
+Or even, you can directly put the requirement version:
+
+.. code-block:: bash
+
+    $ conan require add boost/1.89.0
+    Added 'boost/[>=1.89.0 <2]' as a new requires.
+
+
+Tool and test requirements are also supported:
+
+.. code-block:: bash
+
+    $ conan require add --tool cmake --test gtest
+    Connecting to remote 'conancenter' anonymously
+    Found 54 pkg/version recipes matching cmake/* in conancenter
+    Found 10 pkg/version recipes matching gtest/* in conancenter
+    Added 'cmake/[>=4.2.2 <5]' as a new tool_requires.
+    Added 'gtest/cci.20210126' as a new test_requires.
+
+Use ``--no-remote`` to resolve versions only from the local cache:
+
+.. code-block:: bash
+
+    $ conan require add boost --no-remote
+    Found 2 pkg/version recipes matching boost/* in local cache
+    Added 'boost/[>=1.89.0 <2]' as a new requires.
+
+
+Use ``--folder`` to point to a different recipe location:
+
+.. code-block:: text
+
+    $ conan require add fmt --folder=path/to/conanfile.py
+
+
+conan require remove
+--------------------
+
+.. autocommand::
+    :command: conan require remove -h
+
+Remove any requirement from your *conanfile.py*:
+
+.. code-block:: bash
+
+    $ conan require remove fmt zlib
+    Removed fmt dependency as requires.
+    Removed zlib dependency as requires.
+
+Tool and test requirements are also supported:
+
+.. code-block:: bash
+
+    $ conan require remove --tool cmake --test gtest
+    Removed cmake dependency as tool_requires.
+    Removed gtest dependency as test_requires.
+
+Use ``--folder`` to point to a different recipe location:
+
+.. code-block:: text
+
+    $ conan require remove fmt --folder=path/to/conanfile.py