Remove getNonNullableType application in checkIdentifier

src/compiler/checker.ts

@@ -30525,8 +30525,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         const initialType = isAutomaticTypeInNonNull ? undefinedType :
             assumeInitialized ? (isParameter ? removeOptionalityFromDeclaredType(type, declaration as VariableLikeDeclaration) : type) :
             typeIsAutomatic ? undefinedType : getOptionalType(type);
-        const flowType = isAutomaticTypeInNonNull ? getNonNullableType(getFlowTypeOfReference(node, type, initialType, flowContainer)) :
-            getFlowTypeOfReference(node, type, initialType, flowContainer);
+        const flowType = getFlowTypeOfReference(node, type, initialType, flowContainer);
         // A variable is considered uninitialized when it is possible to analyze the entire control flow graph
         // from declaration to use, and when the variable's declared type doesn't include undefined but the
         // control flow based type does include undefined.

tests/cases/fourslash/wrongEvolvingTypeUnderNonNullAssertion.ts

@@ -0,0 +1,14 @@
+/// <reference path="fourslash.ts" />
+
+// Issue #60514
+
+// @strict: true
+//// declare function foo(): number | undefined
+//// let x;
+//// x = foo();
+//// let [|y2|] = [|x|]!;
+
+const [afterAssertion, beforeAssertion] = test.ranges()
+
+verify.typeAtLocation(beforeAssertion, "number | undefined")
+verify.typeAtLocation(afterAssertion, "number")