lodash: signatures of _.isPlainObject have been changed

lodash/lodash-tests.ts

@@ -6106,10 +6106,24 @@ module TestIsObject {
 }
 
 // _.isPlainObject
-result = <boolean>_.isPlainObject(any);
-result = <boolean>_(1).isPlainObject();
-result = <boolean>_<any>([]).isPlainObject();
-result = <boolean>_({}).isPlainObject();
+module TestIsPlainObject {
+    {
+        let result: boolean;
+
+        result = _.isPlainObject(any);
+        result = _(1).isPlainObject();
+        result = _<any>([]).isPlainObject();
+        result = _({}).isPlainObject();
+    }
+
+    {
+        let result: _.LoDashExplicitWrapper<boolean>;
+
+        result = _(1).chain().isPlainObject();
+        result = _<any>([]).chain().isPlainObject();
+        result = _({}).chain().isPlainObject();
+    }
+}
 
 // _.isRegExp
 module TestIsRegExp {

lodash/lodash.d.ts

@@ -10154,6 +10154,13 @@ declare module _ {
         isPlainObject(): boolean;
     }
 
+    interface LoDashExplicitWrapperBase<T, TWrapper> {
+        /**
+         * see _.isPlainObject
+         */
+        isPlainObject(): LoDashExplicitWrapper<boolean>;
+    }
+
     //_.isRegExp
     interface LoDashStatic {
         /**