Jest matchers can accept many arguments

types/jest/index.d.ts

@@ -8,6 +8,7 @@
 //                 Allan Lukwago <https://github.com/epicallan>
 //                 Ika <https://github.com/ikatyang>
 //                 Waseem Dahman <https://github.com/wsmd>
+//                 Jamie Mason <https://github.com/JamieMason>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 // TypeScript Version: 2.3
 
@@ -240,7 +241,7 @@ declare namespace jest {
     }
 
     interface ExpectExtendMap {
-        [key: string]: (this: MatcherUtils, received: any, actual: any) => { message(): string, pass: boolean };
+        [key: string]: (this: MatcherUtils, received: any, ...actual: any[]) => { message(): string, pass: boolean };
     }
 
     interface SnapshotSerializerOptions {

types/jest/jest-tests.ts

@@ -259,6 +259,12 @@ describe('Extending extend', () => {
                     () => `expected ${received} ${pass ? 'not ' : ''} to be ${actual}`;
                 return { message, pass };
             },
+            toBeVariadicMatcher(received: any, floor: number, ceiling: number) {
+                const pass = received >= floor && received <= ceiling;
+                const message =
+                    () => `expected ${received} ${pass ? 'not ' : ''} to be within range ${floor}-${ceiling}`;
+                return { message, pass };
+            },
             toBeTest(received: any, actual: any) {
                 this.utils.ensureNoExpected(received);
                 this.utils.ensureActualIsNumber(received);