fix(test): toThrow() === toThrow('') (#16308)

src/bun.js/test/expect.zig

@@ -2172,6 +2172,10 @@ pub const Expect = struct {
                         break :brk innerConstructorValue;
                     }
                 }
+            } else if (value.isString()) {
+                // `.toThrow("") behaves the same as `.toThrow()`
+                const s = value.toString(globalThis);
+                if (s.length() == 0) break :brk .zero;
             }
             break :brk value;
         };

test/cli/test/expectations.test.ts

@@ -0,0 +1,11 @@
+describe(".toThrow()", () => {
+  it(".toThrow() behaves the same as .toThrow('')", () => {
+    expect(() => {
+      throw new Error("test");
+    }).toThrow();
+
+    expect(() => {
+      throw new Error("test");
+    }).toThrow("");
+  });
+});