Suggest completions within tuple type arguments

mkantor · mkantor · commit d5bbf02c218f · 2025-08-01T07:47:10.000-04:00
diff --git a/src/services/completions.ts b/src/services/completions.ts
@@ -5794,6 +5794,8 @@ export function getConstraintOfTypeArgumentProperty(node: Node, checker: TypeChe
         case SyntaxKind.TypeLiteral:
         case SyntaxKind.UnionType:
             return t;
+        case SyntaxKind.OpenBracketToken:
+            return checker.getElementTypeOfArrayType(t);
     }
 }
 
diff --git a/tests/cases/fourslash/completionListInTypeLiteralInTypeParameter21.ts b/tests/cases/fourslash/completionListInTypeLiteralInTypeParameter21.ts
@@ -0,0 +1,18 @@
+/// <reference path="fourslash.ts" />
+
+////class Foo<T extends ('one' | 2)[]> {}
+////function foo<T extends ('one' | 2)[]>() {}
+////
+////type A = Foo<[/*0*/]>;
+////new Foo<[/*1*/]>();
+////foo<[/*2*/]>();
+////foo<[/*3*/]>;
+////Foo<[/*4*/]>;
+
+verify.completions(
+    { marker: "0", includes: ['"one"', '2'], isNewIdentifierLocation: true },
+    { marker: "1", includes: ['"one"', '2'], isNewIdentifierLocation: true },
+    { marker: "2", includes: ['"one"', '2'], isNewIdentifierLocation: true },
+    { marker: "3", includes: ['"one"', '2'], isNewIdentifierLocation: true },
+    { marker: "4", includes: ['"one"', '2'], isNewIdentifierLocation: true }
+);

Original file line number	Diff line number	Diff line change
`@@ -5794,6 +5794,8 @@ export function getConstraintOfTypeArgumentProperty(node: Node, checker: TypeChe`
`5794`	`5794`	`case SyntaxKind.TypeLiteral:`
`5795`	`5795`	`case SyntaxKind.UnionType:`
`5796`	`5796`	`return t;`
	`5797`	`+ case SyntaxKind.OpenBracketToken:`
	`5798`	`+ return checker.getElementTypeOfArrayType(t);`
`5797`	`5799`	`}`
`5798`	`5800`	`}`
`5799`	`5801`