This files describes API changes for code that uses the question API.

=== 4.2.1 ===

1) The core_question_generator::update_question has been changed so that it no longer modifies the $question
   object that was passed in. Instead, the update question is returned (which was already the case).
   If you were relying on the old behavioru in your tests, you will need a change like
       $questiongenerator->update_question($question, ...);
   to
       $question = $questiongenerator->update_question($question, ...);
   Also, the $question object returned now has fields questionbankentryid, versionid, version and status.

2) question_stats_cleanup_task now does nothing, and will be removed in Moodle 4.3. It is no longer required. Instead,
   older statistics are deleted whenever a new set are calculated for a particular quiz.

3) In the past, the methods get_last_calculated_time() and get_cached() of \core_question\statistics\responses\analyser
   and \core_question\statistics\questions\all_calculated_for_qubaid_condition
   only returned the pre-computed statistics if they were computed less than 15 minutes ago. Now, they will
   always return any computed statistics that exist. The constants TIME_TO_CACHE in those classes
   will be deprecated in Moodle 4.3.

4) The cache() methods of classes analysis_for_question, analysis_for_subpart, analysis_for_class
   and analysis_for_actual_response now take an optional $calculationtime, which is used the time
   stored in the database. If not given, time() is used.


=== 4.2 ===

1) The question/qengine.js has been deprecated. We create core_question/question_engine
   and core/scroll_manager to replace it.

2) For properties that were previously only declared dynamically, a few classes now include property declarations to support PHP 8.2.
   The affected classes are:
   * restore_qbank_customfields_plugin
   * category_condition
   * tag_condition
   * question_behaviour_attempt_updater
   * question_engine_attempt_upgrader
   * qformat_blackboard_six
   * qtype_multianswer_edit_form
   * qtype_ddimageortext_drop_zone
   * qtype_randomsamatch_qe2_attempt_updater
   * qformat_default

   Some existing code and variables must be removed while working on this issue, including:
   * Removed $replace in class qtype_calculated_variable_substituter
   * Removed $wizarddisplay qtype_calculatedsimple_edit_form::definition_inner()
   * Removed '$question->places[$placeno]->fieldname = $fieldname' in qtype_ddtoimage_renderer_base::formulation_and_controls()
   * Removed $mc->single in qtype_multianswer_test_helper::make_multianswer_question_multiple()

3) display_move_form() in qbank_managecategories\question_category_object class is deprecated and moved the logic to
   the question/bank/managecategories/category.php.

=== 4.1 ===

1) get_bulk_action_key() in core_question\local\bank\bulk_action_base class is deprecated and renamed to get_key().

=== 4.0.5 ===

1) Question bank plugins can now define more than one bulk action. Therefore, plugin_features_base::get_bulk_actions has been
   changed to return an array, rather than a single bulk action class. Please update the plugin_features class in your plugin if necessary.

=== 4.0 ===

Moodle 4.0 included the results of a major project to re-work the question bank.

1) Database changes (as usual, all existing data is updated automatically).
   * Previously there was a single {question} table. This has now been split into three to handle versionning questions:
     - question              - This now has a row for each version of each question. Therefore, some of the metadata
                               (e.g. category) is moved to the next table. However, data that defines how a question works
                               is unchanged, so question type plugins will mostly keep working.
     - question_bank_entries - Each question bank entry is a question that appears in the question bank, which can
                               have many versions.
     - question_versions     - This joins all the versions of a question in the {question} table to the
                               {question_bank_entries} row they belong to.
   * Also, how other parts of the code refer to questions they want to to has changed, to be managed by the core
     API in two new tables.
      - question_references -> Records where a specific question is used.
      - question_set_references -> Records where groups of questions are used (for example random questions in quizzes).
     As a result of this, data from the two quiz tables {quiz_slot} and {quiz_slot_tags} was moved to these new tables.

2) There is a new plugin type 'qbank' for adding features to the question bank. See question/bank/upgrade.txt.

3) Many previously core features have been moved into new plugins, meaning that many old functionsand classes in
   lib/questionlib.php and other locations have been deprecated and moved:
    * Moved to qbank_previewquestion:
       - question_preview_url() is moved to qbank_previewquestion\helper::question_preview_url()
       - question_preview_popup_params() is moved to qbank_previewquestion\helper::question_preview_popup_params()
      the following were really part of the internal implementation of preview, so should not have been used elsewhere,
      but they were also moved (from previewlib.php).
       - restart_preview() => qbank_previewquestion\helper::restart_preview(),
       - question_preview_form_url() => qbank_previewquestion\helper::question_preview_form_url(),
       - question_preview_action_url() => qbank_previewquestion\helper::question_preview_action_url(),
       - question_preview_question_pluginfile() => qbank_previewquestion\helper::question_preview_question_pluginfile(),
       - class preview_options_form => 'qbank_previewquestion\form\preview_options_form',
       - class question_preview_options => 'qbank_previewquestion\output\question_preview_options',
    * Moved to qbank_managecategories:
       - qbank_managecategories\helper::question_remove_stale_questions_from_category()
       - flatten_category_tree() => qbank_managecategories\helper::flatten_category_tree()
       - add_indented_names() => qbank_managecategories\helper::add_indented_names()
       - question_category_select_menu() => qbank_managecategories\helper::question_category_select_menu()
       - get_categories_for_contexts() => qbank_managecategories\helper::get_categories_for_contexts()
       - question_category_options() => qbank_managecategories\helper::question_category_options()
       - question_add_context_in_key() => qbank_managecategories\helper::question_add_context_in_key()
       - question_fix_top_names() => qbank_managecategories\helper::question_fix_top_names()
       - class category_form => qbank_managecategories\form\category_form
       - class question_category_list => qbank_managecategories\question_category_list
       - class question_category_list_item => 'bank_managecategories\question_category_list_item
       - class question_category_object => qbank_managecategories\question_category_object
       - class question_category_edit_form => qbank_managecategories\form\category_form
       - class question_move_form => qbank_managecategories\form\question_move_form
    * Moved to qbank_exporttoxml:
       - question_get_export_single_question_url() -> qbank_exporttoxml\helper::question_get_export_single_question_url().
    * Moved to qbank_exportquestions:
       - class question_export_form => qbank_exportquestions\form\export_form
       - class export_form => qbank_exportquestions\form\export_form
    * Moved to qbank_importquestions:
       - class question_import_form => qbank_importquestions\form\question_import_form
    * Moved to qbank_tagquestion:
       - submit_tags_form and associated external services for question tag,
       - tags_form in question/type,
       - core_question_output_fragment_tags_form() => /question/bank/qbank_tagquestion/lib.php.

4) The following functions in questionlib.php now using type hinting. So, if you call them with the wrong types,
   you will now get fatal errors.
    - is_latest()
    - get_next_version()
    - get_question_version()
    - get_question_bank_entry()
    - core_question_find_next_unused_idnumber()
    - question_module_uses_questions()
    - question_page_type_list()
    - core_question_question_preview_pluginfile()
    - question_rewrite_question_preview_urls()
    - question_rewrite_question_urls()
    - question_get_all_capabilities()
    - question_get_question_capabilities()
    - question_require_capability_on()
    - question_has_capability_on()
    - question_default_export_filename()
    - get_import_export_formats()
    - question_categorylist_parents()
    - question_categorylist()
    - question_make_default_categories()
    - question_get_top_categories_for_contexts()
    - sort_categories_by_tree()
    - print_question_icon()
    - question_sort_tags()
    - _tidy_question()
    - question_preload_questions()
    - question_move_category_to_context()
    - move_question_set_references()
    - question_move_questions_to_category()
    - idnumber_exist_in_question_category()
    - question_move_question_tags_to_new_context()
    - question_delete_activity()
    - question_delete_course_category()
    - question_delete_course()
    - question_delete_context()
    - question_delete_question()
    - delete_question_bank_entry()
    - question_category_in_use()
    - question_category_delete_safe()
    - question_context_has_any_questions()
    - questions_in_use()
    - question_save_qtype_order()
    - question_reorder_qtypes()

5) Function question_hash() from questionlib.php is deprecated without replacement.

6) The following classes have been moved, to better follow Moodle's name-space usage rules:
   'core_question\bank\action_column_base' => 'core_question\local\bank\action_column_base',
   'core_question\bank\checkbox_column' => 'core_question\local\bank\checkbox_column',
   'core_question\bank\column_base' => 'core_question\local\bank\column_base',
   'core_question\bank\edit_menu_column' => 'core_question\local\bank\edit_menu_column',
   'core_question\bank\menu_action_column_base' => 'core_question\local\bank\menu_action_column_base',
   'core_question\bank\menuable_action' => 'core_question\local\bank\menuable_action',
   'core_question\bank\random_question_loader' => 'core_question\local\bank\random_question_loader',
   'core_question\bank\row_base' => 'core_question\local\bank\row_base',
   'core_question\bank\view' => 'core_question\local\bank\view',
   'core_question\bank\copy_action_column' => 'qbank_editquestion\copy_action_column',
   'core_question\bank\edit_action_column' => 'qbank_editquestion\edit_action_column',
   'core_question\bank\creator_name_column' => 'qbank_viewcreator\creator_name_column',
   'core_question\bank\question_name_column' => 'qbank_viewquestionname\viewquestionname_column_helper',
   'core_question\bank\question_name_idnumber_tags_column' => 'qbank_viewquestionname\question_name_idnumber_tags_column',
   'core_question\bank\delete_action_column' => 'qbank_deletequestion\delete_action_column',
   'core_question\bank\export_xml_action_column' => 'qbank_exporttoxml\export_xml_action_column',
   'core_question\bank\preview_action_column' => 'qbank_previewquestion\preview_action_column',
   'core_question\bank\question_text_row' => 'qbank_viewquestiontext\question_text_row',
   'core_question\bank\question_type_column' => 'qbank_viewquestiontype\question_type_column',
   'core_question\bank\tags_action_column' => 'qbank_tagquestion\tags_action_column',
   'core_question\form\tags' => '\qbank_tagquestion\form\tags_form',
   'core_question\output\qbank_chooser' => 'qbank_editquestion\qbank_chooser',
   'core_question\output\qbank_chooser_item' => 'qbank_editquestion\qbank_chooser_item',

7) The Behat class for question-related steps has been renamed to behat_core_question
    to match the expected naming convention. In the unlikely event that you are directly
    referring to the behat_question class name (nothing in the standard Moodle code was)
    then you will have to update your reference.


=== 3.9 ===

1) For years, the ..._questions_in_use callback has been the right way for plugins to
   tell the core question system if questions are required. Previously this callback
   only worked in mods. Now it works in all plugins.

   At the same time, if you are still relying on the legacy ..._question_list_instances
   callback for this, you will now get a debugging warning telling you to upgrade.

2) Previously, the functions question_delete_activity, question_delete_course and
   question_delete_course_category would echo output. This was not correct behaviour for
   a low-level API function. Now, they no longer output. Related to this, the helper
   function they use, question_delete_context, now always returns an empty array.

   This probably won't acutally cause you any problems. However, you may previously
   have had to add expectOutputRegex calls to your unit tests to avoid warnings about
   risky tests. If you have done that, those tests will now fail until you delete that expectation.


=== 3.8 ===

If you have customised the display of the question bank (using $CFG->questionbankcolumns)
then be aware that the default configuration has changed, and you may wish to make
equivalent changes in your customised version. The old column question_name_column
has been replaced by question_name_idnumber_tags_column. The old question_name_column
still exists, so it is safe to continue using it.

There is a new question bank column edit_menu_column which displays all actions
in a drop-down menu, instead of as separate icons. This is now used by default.
Specifically, it gathers all other columns which implement the new interface
menuable_action. If you have made a custom subclasses of action_column_base,
you probably want to implement the new interface. If your column is a simple action,
the easiest way to do this will be to subclass menu_action_column_base. If your action
is more complex, and does not follow the simple pattern that menu_action_column_base
uses, then you will need to implement menuable_action yourself. The commit for
MDL-66816 updates all the core action columns. Looking at that change should make
it clearly the changes you need to make to your columns.


=== 3.7 ===

The code for the is_valid_number function that was duplicated in the
qtype_numerical and qtype_multianswer plugins in the qtype_numerical_edit_form
and qtype_multianswer_edit_form classes has been moved to a static function
in the qtype_numerical class of the qtype_numerical plugin.

The exportprocess function of the qformat_default class doesn't output a blank line
if the result of the writequestion function is null. This permit to qformat plugins
to ignore some questions without the need to overwrite this function.

* The question_preview_cron() has been deleted. Please use \core\task\question_cron_task::execute().
* The question_usage_statistics_cron() has been deleted. Please use \core\task\question_cron_task::execute().
* The method question_bank::cron() has been deleted, please use question related scheduled tasks.

=== 3.5 ===

1) The question format exportprocess function now adds a
   $checkcapabilities boolean to allow questions to be exported in
   certain circumstances.

=== 3.2 ===

1) The following renderers have been deprecated in favour of the renderable
   core_question\output\qbank_chooser and associated render_* method.
    * qbank_chooser
    * qbank_chooser_types
    * qbank_chooser_qtype
    * qbank_chooser_title

=== 3.1 ===

1) The argument $requirecourseid was removed from question_edit_setup() and
   is no longer respected. The behaviour was found to be buggy and now throws
   debugging notices if passed.

=== 2.9 ===

1) Some functions in questionlib.php which were deprecated in the past have now
   been deleted:

   Deprecated since 2.1
    * question_list_instances
    * get_grade_options
    * question_category_isused
    * save_question_options
    * question_get_real_state

   Deprecated since 2.6
    * question_rewrite_questiontext_preview_urls
    * question_send_questiontext_file
    * question_pluginfile no longer falls back to using the old
      {$previewcomponent}_questiontext_preview_pluginfile callback if the new
      {$previewcomponent}_question_preview_pluginfile callback is missing.


=== 2.8 ===

1) This is just a warning that some methods of the question_engine_data_mapper
   class have changed. All these methods are ones that you should not have been
   calling directly from your code, so this should not cause any problems.
   The changed methods are:
    * insert_question_attempt
    * insert_step_data
    * update_question_attempt_step


=== 2.7 ===

1)  Changes to class question_bank_view:

    Filters, including $recurse and $showhidden, are now implemented as
    pluggable \core_question\bank\search\condition classes.

    Therefore $recurse and $showhidden are no longer passed to the following functions:
        protected function display_options [deprecated, use display_options_form()]
        protected function build_query_sql [deprecated, use build_query()]

    protected function display_category_form() is deprecated. Use \core_question\bank\search\category_condition

    protected function display_category_form_checkbox deprecated use html_writer::checkbox and separate JavaScript

To add filters, local plugins can now implement the function local_[pluginname]_get_question_bank_search_conditions,

2) To make columns available to question_bank_view, plugins can extend core_question\bank\column_base.
   Users may choose to display additional columns by setting $CFG->questionbankcolumns to a comma-delimited list of columns.

3) The subsort separator has changed from _ to - in order to distinuguish subsorts vs frankenstyle component separators.

4) Because of the move to autoloading, $knowncolumntypes and known_field_types() are no longer used.

5) question_bank_column_base and it's derived classes have been namespaced to core_question\bank\column_base.


=== 2.6 ===

1) Modules using the question bank MUST now declare their use of it with the xxx_supports()
   flag FEATURE_USES_QUESTIONS. question_module_uses_questions() should be used to determine
   if a module uses questions.

2) It is sometimes necessary to display bits of question content without having
   and attempt (question_usage) in progress. Two examples of this are the option
   in the question bank to display the questiontext, and in the quiz statistics
   report, where it displays the question text above the report.

   Previously, this display was done using a special method that only worked for
   the question text, but which would not work for other parts of the question.
   That old mechanism has been deprecated, and there is a new method that you
   should use.

   To display the question, replace calls to question_rewrite_questiontext_preview_urls
   with calls to question_rewrite_question_preview_urls. Because the new function
   is more flexibile, you have to pass more arguments.

   To perform the necessary permission checks when the file is downloaded, you need
   to implement the callback [component name]_question_preview_pluginfile.
   (Previously you implemented [component name]_questiontext_preview_pluginfile.)
   quiz_statistics_question_preview_pluginfile is an example of what to do.

   question_send_questiontext_file has been deprecated. It is no longer necessary.

   To ensure you are no longer using or defining any deprecated functions,
   search for the regular expression:
   question_rewrite_questiontext_preview_urls|_questiontext_preview_pluginfile|question_send_questiontext_file

3) The argument list for core_question_renderer::mark_summary has changed.
   Please update your calls. (The most likely scenario for this is if you have
   overridden core_question_renderer::info in your own renderer.) You need to
   make a change like:
   - $this->mark_summary($qa, $options);
   + $this->mark_summary($qa, $behaviouroutput, $options);
