Improve empty test case error messages (denoland#3514)

std/testing/mod.ts

@@ -10,6 +10,7 @@ import {
  yellow,
  italic
 } from "../fmt/colors.ts";
+import { assert } from "./asserts.ts";
 export type TestFunction = () => void | Promise<void>;
 
 export interface TestDefinition {
@@ -121,14 +122,28 @@ export function test(
  throw new Error("Missing test function");
  }
  name = t;
+ if (!name) {
+ throw new Error("The name of test case can't be empty");
+ }
+ } else if (typeof t === "function") {
+ fn = t;
+ name = t.name;
+ if (!name) {
+ throw new Error("Test function can't be anonymous");
+ }
  } else {
- fn = typeof t === "function" ? t : t.fn;
+ fn = t.fn;
+ if (!fn) {
+ throw new Error("Missing test function");
+ }
  name = t.name;
+ if (!name) {
+ throw new Error("The name of test case can't be empty");
+ }
  }
+ assert(!!name, "The name of test case shouldn't be empty");
+ assert(!!fn, "Test function shouldn't be empty");
 
- if (!name) {
- throw new Error("Test function may not be anonymous");
- }
  if (filter(name)) {
  candidates.push({ fn, name });
  } else {

std/testing/test.ts

@@ -260,4 +260,34 @@ test("test fn overloading", (): void => {
  assert(true);
 });
 
+test("The name of test case can't be empty", () => {
+ assertThrows(
+ () => {
+ test("", () => {});
+ },
+ Error,
+ "The name of test case can't be empty"
+ );
+ assertThrows(
+ () => {
+ test({
+ name: "",
+ fn: () => {}
+ });
+ },
+ Error,
+ "The name of test case can't be empty"
+ );
+});
+
+test("test function can't be anonymous", () => {
+ assertThrows(
+ () => {
+ test(function() {});
+ },
+ Error,
+ "Test function can't be anonymous"
+ );
+});
+
 runIfMain(import.meta);