Merge pull request #30094 from Kingwl/improve_completions_for_optional_props

check completions with assignable rather than identity

Author: DanielRosenwasser

src/compiler/checker.ts

@@ -7406,7 +7406,7 @@ namespace ts {
                 const nameType = property.name && getLiteralTypeFromPropertyName(property.name);
                 const name = nameType && isTypeUsableAsPropertyName(nameType) ? getPropertyNameFromType(nameType) : undefined;
                 const expected = name === undefined ? undefined : getTypeOfPropertyOfType(contextualType, name);
-                return !!expected && isLiteralType(expected) && !isTypeIdenticalTo(getTypeOfNode(property), expected);
+                return !!expected && isLiteralType(expected) && !isTypeAssignableTo(getTypeOfNode(property), expected);
             });
         }
 

tests/cases/fourslash/completionsWithOptionalProperties.ts

@@ -0,0 +1,18 @@
+/// <reference path="fourslash.ts" />
+// @strict: true
+
+//// interface Options {
+////     hello?: boolean;
+////     world?: boolean;
+//// }
+//// declare function foo(options?: Options): void;
+//// foo({
+////     hello: true,
+////     /**/
+//// });
+
+verify.completions({
+    marker: "",
+    includes: ['world']
+});
+