Taxonomy views needs filter/field on original language

I think there is a problem with the Description field here though. It seems that it's added to the views data in the default class in a way that's different from how the Taxonomy-specific class was doing it. Needs further investigation.

I am pretty sure it is exposed as $data['taxonomy_term_field_data']['description.value']

+++ b/core/modules/taxonomy/src/TermViewsData.php
@@ -96,42 +68,21 @@ public function getViewsData() {
     $data['taxonomy_term_field_data']['name'] = array(
-      'title' => t('Name'),
       'help' => t('The taxonomy term name.'),
       'field' => array(
         'id' => 'taxonomy',
       ),
-      'sort' => array(
-        'id' => 'standard',
-      ),
       'filter' => array(
-        'id' => 'string',
         'help' => t('Taxonomy term name.'),
       ),
       'argument' => array(
-        'id' => 'string',
         'help' => t('Taxonomy term name.'),
         'many to one' => TRUE,
         'empty field name' => t('Uncategorized'),
       ),
-    );
+    ) + $data['taxonomy_term_field_data']['name'];
...
-    $data['taxonomy_term_field_data']['weight'] = array(
-      'title' => t('Weight'),
-      'help' => t('The term weight field'),
-      'field' => array(
-        'id' => 'numeric',
-      ),
-      'sort' => array(
-        'id' => 'standard',
-      ),
-      'filter' => array(
-        'id' => 'numeric',
-      ),
-      'argument' => array(
-        'id' => 'numeric',
-      ),
-    );
+    $data['taxonomy_term_field_data']['weight']['help'] = t('The term weight field');

Ha, I thought we don't want to do that :)

1. +++ b/core/modules/views/src/Entity/View.php
   @@ -143,6 +143,13 @@ public function label() {
    
      /**
   +   * Returns the base table name.
   +   */
   +  public function getBaseTable() {
   +    return $this->base_table;
   +  }
   +
   
   +++ b/core/modules/views/src/Plugin/views/relationship/GroupwiseMax.php
   @@ -127,7 +127,7 @@ public function buildOptionsForm(&$form, FormStateInterface $form_state) {
   -      if ($view->base_table == $this->definition['base'] && !empty($view->display['default']['display_options']['fields'])) {
   +      if ($view->getBaseTable() == $this->definition['base'] && !empty($view->display['default']['display_options']['fields'])) {
   

   Not sure whether we really need all those getters or just using $view->get('base_table') would be enough.

2. +++ b/core/modules/views/src/Entity/View.php
   index 2477885..1439bd2 100644
   --- a/core/modules/views/src/EntityViewsData.php
   
   --- a/core/modules/views/src/EntityViewsData.php
   +++ b/core/modules/views/src/EntityViewsData.php
   

   Can we please expand the test coverage now that we change something in this file?

3. +++ b/core/modules/views/src/EntityViewsData.php
   @@ -250,113 +240,119 @@ protected function mapFieldDefinition($table, $field_name, FieldDefinitionInterf
   -    $process_method = 'processViewsDataFor' . Container::camelize($data_type);
   +    // Do post-processing for a few field types.
   +
   +    $process_method = 'processViewsDataFor' . Container::camelize($field_type);
        if (method_exists($this, $process_method)) {
   

   These extra lines looks kind of wrong.

Great work!

1. +++ b/core/modules/views/src/EntityViewsData.php
   @@ -226,22 +226,12 @@ protected function mapFieldDefinition($table, $field_name, FieldDefinitionInterf
   +    $multiple = (count($field_column_mapping) > 1);
        $first = TRUE;
   ...
   -      $schema = $field_schema['columns'][$field_column_name];
   -      // We want to both have an entry in the views data for the actual field,
   -      // but also each additional schema field, for example the file
   -      // description.
   -      // @todo Introduce a concept of the "main" schema field for a field item.
   -      //   This would be the FID for a file reference for example.
   -      // @see https://www.drupal.org/node/2337517
   ...
   +      $views_field_name = ($multiple) ? $field_name . '__' . $field_column_name : $field_name;
   +      $table_data[$views_field_name] = $this->mapSingleFieldViewsData($table, $field_name, $field_definition_type, $field_column_name, $field_schema['columns'][$field_column_name]['type'], $first, $field_definition);
   +      $first = FALSE;
   
   @@ -250,113 +240,119 @@ protected function mapFieldDefinition($table, $field_name, FieldDefinitionInterf
        if ($first) {
          $views_field['title'] = $field_definition->getLabel();
        }
        else {
   -      $views_field['title'] = $field_definition->getLabel() . " ($schema_field_name)";
   +      $views_field['title'] = $field_definition->getLabel() . " ($column_name)";
        }
   

   Can we try to not drop the todo and still keep some documentation? There is a still a big difference between the first one and the other one on the level of the sitebuilder.

2. +++ b/core/modules/views/src/EntityViewsData.php
   @@ -250,113 +240,119 @@ protected function mapFieldDefinition($table, $field_name, FieldDefinitionInterf
   +    switch ($field_type) {
   +
   +      // Special case a few field types.
   +
   +      case 'timestamp':
   

   Do we really use that much of new empty lines?

3. +++ b/core/modules/views/src/EntityViewsData.php
   @@ -250,113 +240,119 @@ protected function mapFieldDefinition($table, $field_name, FieldDefinitionInterf
        if (method_exists($this, $process_method)) {
   -      $this->{$process_method}($table, $field_definition, $views_field);
   +      $this->{$process_method}($table, $field_definition, $views_field, $column_name);
        }
   
   @@ -395,6 +391,13 @@ protected function processViewsDataForLanguage($table, FieldDefinitionInterface
      protected function processViewsDataForEntityReference($table, FieldDefinitionInterface $field_definition, array &$views_field) {
   

   Shouldn't we update the existing methods to also accept the $column_name ?

4. +++ b/core/modules/views/src/EntityViewsData.php
   @@ -426,6 +429,26 @@ protected function processViewsDataForEntityReference($table, FieldDefinitionInt
   +   * Processes the views data for a text field with formatting.
   ...
   +   * @param string $table
   +   *   The table the language field is added to.
   

   Note: this is not about the language but actually about text fields.

Awesome, I think this is ready to fly now! More work ins coming.

Committed 61de3bd and pushed to 8.0.x. Thanks!