diff --git a/scripts/apidoc/signature.ts b/scripts/apidoc/signature.ts
index 7db46b2c5b1..ce0379883a3 100644
--- a/scripts/apidoc/signature.ts
+++ b/scripts/apidoc/signature.ts
@@ -78,7 +78,7 @@ function mdToHtml(md: string): string {
 
 export function analyzeSignature(
   signature: SignatureReflection,
-  moduleName: string,
+  moduleName: string | null,
   methodName: string
 ): Method {
   const parameters: MethodParameter[] = [];
diff --git a/test/scripts/apidoc/signature.spec.ts b/test/scripts/apidoc/signature.spec.ts
index 919ac2447f7..f55c10f8d0a 100644
--- a/test/scripts/apidoc/signature.spec.ts
+++ b/test/scripts/apidoc/signature.spec.ts
@@ -36,11 +36,7 @@ describe('signature', () => {
     it.each(Object.keys(expected).sort())('%s', (name) => {
       const method = methods[name];
       expect(method, `Method ${name} to be defined`).toBeDefined();
-      const actual = analyzeSignature(
-        method.signatures[0],
-        '' /* null */,
-        method.name
-      );
+      const actual = analyzeSignature(method.signatures[0], null, method.name);
       actuals[name] = actual;
 
       expect(prettyJson(actual)).toBe(prettyJson(expected[name]));