Issue #2987598 by eliclaggett, alexpott, Lendude, Sam152: View's pagination doesn't carry the exposed filter value

core/modules/views/src/Form/ViewsExposedForm.php

@@ -183,7 +183,7 @@ class ViewsExposedForm extends FormBase {
           //   https://www.drupal.org/node/342316 is resolved.
           $checked = Checkboxes::getCheckedCheckboxes($value);
           foreach ($checked as $option_id) {
-            $view->exposed_raw_input[$key][] = $value[$option_id];
+            $view->exposed_raw_input[$key][$option_id] = $value[$option_id];
           }
         }
         else {

core/modules/views/tests/modules/views_test_config/test_views/views.view.test_exposed_form_pager.yml

@@ -0,0 +1,173 @@
+langcode: en
+status: true
+dependencies:
+  config:
+  - core.entity_view_mode.node.teaser
+  module:
+  - node
+id: test_exposed_form_pager
+label: ''
+module: views
+description: ''
+tag: ''
+base_table: node_field_data
+base_field: nid
+core: '8'
+display:
+  default:
+    display_options:
+      access:
+        type: none
+      cache:
+        type: tag
+      exposed_form:
+        options:
+          reset_button: true
+        type: basic
+      filters:
+        type:
+          id: type
+          table: node_field_data
+          field: type
+          relationship: none
+          group_type: group
+          admin_label: ''
+          operator: in
+          value: {  }
+          group: 1
+          exposed: true
+          expose:
+            operator_id: type_op
+            label: 'Content: Type'
+            description: 'Exposed description'
+            use_operator: false
+            operator: ''
+            identifier: type
+            required: false
+            remember: false
+            multiple: true
+            remember_roles:
+              authenticated: authenticated
+              anonymous: '0'
+              administrator: '0'
+            reduce: false
+          is_grouped: false
+          group_info:
+            label: ''
+            description: ''
+            identifier: ''
+            optional: true
+            widget: select
+            multiple: false
+            remember: false
+            default_group: All
+            default_group_multiple: {  }
+            group_items: {  }
+          plugin_id: in_operator
+          entity_type: node
+          entity_field: type
+        created:
+          id: created
+          table: node_field_data
+          field: created
+          relationship: none
+          group_type: group
+          admin_label: ''
+          operator: between
+          value:
+            min: ''
+            max: ''
+            value: ''
+            type: offset
+          group: 1
+          exposed: true
+          expose:
+            operator_id: created_op
+            label: 'Authored on'
+            description: ''
+            use_operator: false
+            operator: created_op
+            identifier: created
+            required: false
+            remember: false
+            multiple: false
+            remember_roles:
+              authenticated: authenticated
+              anonymous: '0'
+              administrator: '0'
+            placeholder: ''
+            min_placeholder: ''
+            max_placeholder: ''
+          is_grouped: false
+          group_info:
+            label: ''
+            description: ''
+            identifier: ''
+            optional: true
+            widget: select
+            multiple: false
+            remember: false
+            default_group: All
+            default_group_multiple: {  }
+            group_items: {  }
+          entity_type: node
+          entity_field: created
+          plugin_id: date
+      pager:
+        type: full
+        options:
+          items_per_page: 2
+          offset: 0
+          id: 0
+          total_pages: null
+          tags:
+            previous: '‹ Previous'
+            next: 'Next ›'
+            first: '« First'
+            last: 'Last »'
+          expose:
+            items_per_page: false
+            items_per_page_label: 'Items per page'
+            items_per_page_options: '5, 10, 25, 50'
+            items_per_page_options_all: false
+            items_per_page_options_all_label: '- All -'
+            offset: false
+            offset_label: Offset
+          quantity: 9
+      query:
+        options:
+          query_comment: ''
+        type: views_query
+      style:
+        type: default
+      row:
+        type: 'entity:node'
+      display_extenders: {  }
+    display_plugin: default
+    display_title: Master
+    id: default
+    position: 0
+    cache_metadata:
+      max-age: -1
+      contexts:
+      - 'languages:language_interface'
+      - url
+      - url.query_args
+      - 'user.node_grants:view'
+      tags: {  }
+  page_1:
+    display_options:
+      path: test_exposed_form_pager
+      display_extenders: {  }
+    display_plugin: page
+    display_title: Page
+    id: page_1
+    position: 0
+    cache_metadata:
+      max-age: -1
+      contexts:
+      - 'languages:language_interface'
+      - url
+      - url.query_args
+      - 'user.node_grants:view'
+      tags: {  }

core/modules/views/tests/src/Functional/Plugin/ExposedFormTest.php

@@ -24,7 +24,7 @@ class ExposedFormTest extends ViewTestBase {
    *
    * @var array
    */
-  public static $testViews = ['test_exposed_form_buttons', 'test_exposed_block', 'test_exposed_form_sort_items_per_page'];
+  public static $testViews = ['test_exposed_form_buttons', 'test_exposed_block', 'test_exposed_form_sort_items_per_page', 'test_exposed_form_pager'];
 
   /**
    * Modules to enable.
@@ -381,4 +381,32 @@ class ExposedFormTest extends ViewTestBase {
     $this->assertRaw('<div class="views-row">', 'Views result shown.');
   }
 
+  /**
+   * Tests the exposed form with a pager.
+   */
+  public function testExposedFilterPagination() {
+    $this->drupalCreateContentType(['type' => 'post']);
+    // Create some random nodes.
+    for ($i = 0; $i < 5; $i++) {
+      $this->drupalCreateNode(['type' => 'post']);
+    }
+
+    $this->drupalGet('test_exposed_form_pager');
+    $this->getSession()->getPage()->fillField('type[]', 'post');
+    $this->getSession()->getPage()->fillField('created[min]', '-1 month');
+    $this->getSession()->getPage()->fillField('created[max]', '+1 month');
+
+    // Ensure the filters can be applied.
+    $this->getSession()->getPage()->pressButton('Apply');
+    $this->assertFieldByName('type[]', 'post');
+    $this->assertFieldByName('created[min]', '-1 month');
+    $this->assertFieldByName('created[max]', '+1 month');
+
+    // Ensure the filters are still applied after pressing next.
+    $this->clickLink('Next ›');
+    $this->assertFieldByName('type[]', 'post');
+    $this->assertFieldByName('created[min]', '-1 month');
+    $this->assertFieldByName('created[max]', '+1 month');
+  }
+
 }

core/modules/views/tests/src/Kernel/Plugin/ExposedFormRenderTest.php

@@ -136,7 +136,7 @@ class ExposedFormRenderTest extends ViewsKernelTestBase {
     $expected = [
       'type' => 'All',
       'type_with_default_value' => 'article',
-      'multiple_types_with_default_value' => ['article'],
+      'multiple_types_with_default_value' => ['article' => 'article'],
     ];
     $this->assertSame($view->exposed_raw_input, $expected);
   }