diff --git a/packages/lit-analyzer/src/rules/util/type/is-assignable-in-event-binding.ts b/packages/lit-analyzer/src/rules/util/type/is-assignable-in-event-binding.ts
index 6f93b40a..1a45aa32 100644
--- a/packages/lit-analyzer/src/rules/util/type/is-assignable-in-event-binding.ts
+++ b/packages/lit-analyzer/src/rules/util/type/is-assignable-in-event-binding.ts
@@ -1,4 +1,4 @@
-import { SimpleType, SimpleTypeKind, toTypeString } from "ts-simple-type";
+import { SimpleType, typeToString } from "ts-simple-type";
 import { HtmlNodeAttr } from "../../../analyze/types/html-node/html-node-attr-types";
 import { RuleModuleContext } from "../../../analyze/types/rule/rule-module-context";
 import { rangeFromHtmlNodeAttr } from "../../../analyze/util/range-util";
@@ -10,14 +10,14 @@ export function isAssignableInEventBinding(
 	context: RuleModuleContext
 ): boolean | undefined {
 	const expectedType: SimpleType = {
-		kind: SimpleTypeKind.FUNCTION,
-		returnType: { kind: SimpleTypeKind.VOID },
-		argTypes: [
+		kind: "FUNCTION",
+		returnType: { kind: "VOID" },
+		parameters: [
 			{
-				name: 'event',
+				name: "event",
 				type: typeA,
 				optional: false,
-				spread: false,
+				rest: false,
 				initializer: false
 			}
 		]
@@ -26,7 +26,7 @@ export function isAssignableInEventBinding(
 	if (!isAssignableToType({ typeA: expectedType, typeB }, context)) {
 		context.report({
 			location: rangeFromHtmlNodeAttr(htmlAttr),
-			message: `Type '${toTypeString(typeB)}' is not assignable to '${toTypeString(expectedType)}'`
+			message: `Type '${typeToString(typeB)}' is not assignable to '${typeToString(expectedType)}'`
 		});
 
 		return false;
diff --git a/packages/lit-analyzer/test/rules/no-incompatible-type-binding.ts b/packages/lit-analyzer/test/rules/no-incompatible-type-binding.ts
index c73a0ed1..bf708aa1 100644
--- a/packages/lit-analyzer/test/rules/no-incompatible-type-binding.ts
+++ b/packages/lit-analyzer/test/rules/no-incompatible-type-binding.ts
@@ -225,21 +225,30 @@ html\`<input step="\${myDirective("foo")}" /> \`
 	hasDiagnostic(t, diagnostics, "no-incompatible-type-binding");
 });
 
-test("Event binding: event handler is assignable to valid event", t => {
-	const { diagnostics } = getDiagnostics([makeElement({ events: ["foo-event"] }), 'html`<my-element @foo-event=${(ev) => {}}></my-element>`']);
+tsTest("Event binding: event handler is assignable to valid event", t => {
+	const { diagnostics } = getDiagnostics([makeElement({ events: ["foo-event"] }), "html`<my-element @foo-event=${(ev) => {}}></my-element>`"]);
 	hasNoDiagnostics(t, diagnostics);
 });
 
-test("Event binding: event handler is assignable to valid typed event", t => {
-	const { diagnostics } = getDiagnostics([makeElement({ events: ["{MouseEvent} foo-event"] }), 'html`<my-element @foo-event=${(ev: MouseEvent) => {}}></my-element>`']);
+tsTest("Event binding: event handler is assignable to valid typed event", t => {
+	const { diagnostics } = getDiagnostics([
+		makeElement({ events: ["{MouseEvent} foo-event"] }),
+		"html`<my-element @foo-event=${(ev: MouseEvent) => {}}></my-element>`"
+	]);
 	hasNoDiagnostics(t, diagnostics);
 });
 
-test("Event binding: invalid event handler is not assignable to typed event", t => {
-	const { diagnostics } = getDiagnostics([makeElement({ events: ["{MouseEvent} foo-event"] }), 'html`<my-element @foo-event=${(ev: KeyboardEvent) => {}}></my-element>`']);
+tsTest("Event binding: invalid event handler is not assignable to typed event", t => {
+	const { diagnostics } = getDiagnostics([
+		makeElement({ events: ["{MouseEvent} foo-event"] }),
+		"html`<my-element @foo-event=${(ev: KeyboardEvent) => {}}></my-element>`"
+	]);
 	hasDiagnostic(t, diagnostics, "no-incompatible-type-binding");
 });
 
-test("Event binding: invalid event handler is not assignable to event", t => {
-	const { diagnostics } = getDiagnostics([makeElement({ events: ["foo-event"] }), 'html`<my-element @foo-event=${(arg: boolean) => {}}></my-element>`']);
+tsTest("Event binding: invalid event handler is not assignable to event", t => {
+	const { diagnostics } = getDiagnostics([
+		makeElement({ events: ["foo-event"] }),
+		"html`<my-element @foo-event=${(arg: boolean) => {}}></my-element>`"
+	]);
 });