More docs on generators (#3887)

* More docs on generators

* More docs for generators_info

Author: AbrilRBS

reference/conanfile/attributes/consumers.inc

@@ -96,6 +96,19 @@ Should be only filled in the ``package_info()`` method.
       Read here :ref:`the complete reference of self.conf_info <conan_conanfile_model_conf_info>`.
 
 
+generators_info
+---------------
+
+.. include:: ../../common/experimental_warning.inc
+
+Generators to be passed to the dependant recipes.
+Should be only filled in the ``package_info()`` method.
+
+.. seealso::
+
+      See :ref:`an example usage here <reference_commands_custom_generators_tool_requires>`
+      and :ref:`the complete reference of self.generators_info <conan_conanfile_model_generators_info>`.
+
 deprecated
 ----------
 

reference/conanfile/methods/package_info.rst

@@ -296,6 +296,33 @@ configuration as:
 Note that this only propagates from the immediate, direct ``tool_requires`` of a recipe.
 
 
+.. _conan_conanfile_model_generators_info:
+
+generators_info
+---------------
+
+.. include:: ../../../common/experimental_warning.inc
+
+
+``tool_requires`` in the build context can inject generators into the recipe,
+by adding them to the ``generators_info`` list inside the ``package_info`` method.
+This is useful to inject custom generators into the recipe, that will be used by the consumers of the package,
+just as if they were declared in their ``generators`` attribute.
+
+.. code-block:: python
+
+    class MyGenerator:
+        def __init__(self, conanfile):
+            self._conanfile = conanfile
+
+        def generate(self):
+            self.output.info(f"Calling custom generator for {conanfile}")
+
+    def package_info(self):
+        self.generators_info.append(MyGenerator)
+
+Note that this only propagates from the immediate, direct ``tool_requires`` of a recipe.
+
 
 .. note::
 

reference/extensions/custom_generators.rst

@@ -100,6 +100,8 @@ argument:
     conan install --requires=zlib/1.2.13 -g MyGenerator
 
 
+.. _reference_commands_custom_generators_tool_requires:
+
 Generators from tool_requires
 -----------------------------