Issue #1948884 by vijaycs85, YesCT, Gábor Hojtsy: Create configuration schemas...

Issue #1948884 by vijaycs85, YesCT, Gábor Hojtsy: Create configuration schemas for block and custom_block() modules.

core/modules/block/config/schema/block.schema.yml

+# Schema for the configuration files of the Block module.
+
+block.block.*.*:
+  type: mapping
+  label: 'Block'
+  mapping:
+    id:
+      type: string
+      label: 'ID'
+    label:
+      type: label
+      label: 'Title'
+    label_display:
+      type: string
+      label: 'Display title'
+    uuid:
+      type: string
+      label: 'UUID'
+    region:
+      type: string
+      label: 'Region'
+    weight:
+      type: integer
+      label: 'Weight'
+    module:
+      type: string
+      label: 'Module'
+    status:
+      type: boolean
+      label: 'Status'
+    visibility:
+      type: mapping
+      label: 'Visibility settings'
+      mapping:
+        path:
+          type: mapping
+          label: 'Pages'
+          mapping:
+            visibility:
+              type: integer
+              label: 'Visibility'
+            pages:
+              type: string
+              label: 'Show block on specific pages'
+        role:
+          type: mapping
+          label: 'Roles'
+          mapping:
+            roles:
+              type: sequence
+              label: 'Show block for specific roles'
+              sequence:
+                - type: string
+                  label: 'Role'
+        node_type:
+          type: mapping
+          label: 'Content types'
+          mapping:
+            types:
+              type: sequence
+              label: 'Show block for specific content types'
+              sequence:
+               - type: string
+                 label: 'Node type'
+        visibility__active_tab:
+          type: string
+          label: 'Visibility active tab'
+    plugin:
+      type: string
+      label: 'Plugin'
+    settings:
+      type: mapping
+      label: 'Block settings'
+      mapping:
+        admin_label:
+          type: label
+          label: 'Description'
+        cache:
+          type: integer
+          label: 'Cache'
+        status:
+          type: boolean
+          label: 'Status'
+        info:
+          type: label
+          label: 'Admin info'
+        view_mode:
+          type: string
+          label: 'View mode'
+    langcode:
+      type: string
+      label: 'Language code'

core/modules/block/custom_block/config/schema/custom_block.schama.yml

+# Schema for the configuration files of the Custom Block module.
+
+custom_block.type.*:
+  type: mapping
+  label: 'Custom block type settings'
+  mapping:
+    id:
+      type: string
+      label: 'Machine-readable name'
+    uuid:
+      type: string
+      label: 'UUID'
+    label:
+      type: label
+      label: 'Label'
+    revision:
+      type: integer
+      label: 'Create new revision'
+    description:
+      type: text
+      label: 'Description'
+    status:
+      type: boolean
+      label: 'Status'
+    langcode:
+      type: string
+      label: 'Default language'

core/modules/system/lib/Drupal/system/Tests/Module/ModuleTestBase.php

@@ -104,6 +104,11 @@ function assertModuleConfig($module) {
     // Verify that the module's default config directory is not empty and
     // contains default configuration files (instead of something else).
     $all_names = $module_file_storage->listAll();
+    if (empty($all_names)) {
+      // Module has an empty config directory. For example it might contain a
+      // schema directory.
+      return;
+    }
     $this->assertTrue($all_names);
 
     // Look up each default configuration object name in the active