diff --git a/tests/cases/fourslash/parameterWithDestructuring.ts b/tests/cases/fourslash/parameterWithDestructuring.ts
index e8026125e2b..72dfefd553a 100644
--- a/tests/cases/fourslash/parameterWithDestructuring.ts
+++ b/tests/cases/fourslash/parameterWithDestructuring.ts
@@ -1,11 +1,22 @@
 /// <reference path='fourslash.ts'/>
 
+// Repros from issues #4949 and #4818
+
 ////const result = [{ foo: 'hello' }]
 ////    .map(({ /*1*/foo }) => /*2*/foo)
 ////    .map(foo => foo);
+////
+////const f = (foo: (bar: string[]) => void) => { };
+////
+////f(([a, b]) => {
+////    /*3*/a.charAt(0); // Not okay: inferred as `any`
+////});
 
 goTo.marker('1');
 verify.quickInfoIs('var foo: string');
 
 goTo.marker('2');
 verify.quickInfoIs('var foo: string');
+
+goTo.marker('3');
+verify.quickInfoIs('var a: string');