[config] transform plugin deprecations before checking for unused settings

src/server/config/complete.js

@@ -20,13 +20,23 @@
 import { difference } from 'lodash';
 import { transformDeprecations } from './transform_deprecations';
 import { unset, formatListAsProse, getFlattenedObject } from '../../utils';
+import { createTransform, Deprecations } from '../../deprecation';
+
 
 const getFlattenedKeys = object => (
   Object.keys(getFlattenedObject(object))
 );
 
-const getUnusedConfigKeys = (disabledPluginSpecs, rawSettings, configValues) => {
-  const settings = transformDeprecations(rawSettings);
+const getUnusedConfigKeys = (plugins, disabledPluginSpecs, rawSettings, configValues) => {
+  // transform deprecated core settings
+  let settings = transformDeprecations(rawSettings);
+
+  // transform deprecated plugin settings
+  plugins.forEach(({ spec }) => {
+    const deprecationsProvider = spec.getDeprecationsProvider();
+    if (!deprecationsProvider) return;
+    settings = createTransform(deprecationsProvider(Deprecations))(settings);
+  });
 
   // remove config values from disabled plugins
   for (const spec of disabledPluginSpecs) {
@@ -52,7 +62,7 @@ export default function (kbnServer, server, config) {
     return kbnServer.config;
   });
 
-  const unusedKeys = getUnusedConfigKeys(kbnServer.disabledPluginSpecs, kbnServer.settings, config.get())
+  const unusedKeys = getUnusedConfigKeys(kbnServer.plugins, kbnServer.disabledPluginSpecs, kbnServer.settings, config.get())
     .map(key => `"${key}"`);
 
   if (!unusedKeys.length) {

src/server/config/complete.test.js

@@ -34,6 +34,7 @@ describe('server/config completeMixin()', function () {
       settings = {},
       configValues = {},
       disabledPluginSpecs = [],
+      plugins = [],
     } = options;
 
     const server = {
@@ -48,7 +49,8 @@ describe('server/config completeMixin()', function () {
       settings,
       server,
       config,
-      disabledPluginSpecs
+      disabledPluginSpecs,
+      plugins
     };
 
     const callCompleteMixin = () => {
@@ -220,6 +222,28 @@ describe('server/config completeMixin()', function () {
       callCompleteMixin();
       sinon.assert.calledOnce(transformDeprecations);
     });
+
+    it('should transform deprecated plugin settings', () => {
+      const { callCompleteMixin } = setup({
+        settings: {
+          foo1: 'bar'
+        },
+        configValues: {
+          foo2: 'bar'
+        },
+        plugins: [
+          {
+            spec: {
+              getDeprecationsProvider() {
+                return ({ rename }) => [rename('foo1', 'foo2')];
+              }
+            }
+          }
+        ],
+      });
+
+      expect(callCompleteMixin).not.toThrowError();
+    });
   });
 
   describe('disabled plugins', () => {