Merge pull request #33228 from OliverJAsh/oja/lodash-is-object-type-guard

Lodash: `isObject`: user-defined type guard

types/lodash/common/lang.d.ts

@@ -1224,14 +1224,14 @@ declare module "../index" {
          * @param value The value to check.
          * @return Returns true if value is an object, else false.
          */
-        isObject(value?: any): boolean;
+        isObject(value?: any): value is object;
     }
 
     interface LoDashImplicitWrapper<TValue> {
         /**
          * see _.isObject
          */
-        isObject(): boolean;
+        isObject(): this is LoDashImplicitWrapper<object>;
     }
 
     interface LoDashExplicitWrapper<TValue> {

types/lodash/fp.d.ts

@@ -1984,7 +1984,7 @@ declare namespace _ {
     type LodashIsNil = (value: any) => value is null | undefined;
     type LodashIsNull = (value: any) => value is null;
     type LodashIsNumber = (value: any) => value is number;
-    type LodashIsObject = (value: any) => boolean;
+    type LodashIsObject = (value: any) => value is object;
     type LodashIsObjectLike = (value: any) => boolean;
     type LodashIsPlainObject = (value: any) => boolean;
     type LodashIsRegExp = (value: any) => value is RegExp;

types/lodash/lodash-tests.ts

@@ -4291,6 +4291,12 @@ fp.now(); // $ExpectType number
     _(42).isObject(); // $ExpectType boolean
     _.chain([]).isObject(); // $ExpectType LoDashExplicitWrapper<boolean>
     fp.isObject(anything); // $ExpectType boolean
+    if (fp.isObject(anything)) {
+        anything; // $ExpectType object
+    }
+    if (_.isObject(anything)) {
+        anything; // $ExpectType object
+    }
 }
 
 // _.isObjectLike