     func test_UUID_JSON() {
         for uuid in uuidValues {
             // We have to wrap the UUID since we cannot have a top-level string.
-            XCTAssertTrue(expectRoundTripEqualityThroughJSON(for: UUIDCodingWrapper(uuid)))
+            do {
+                try expectRoundTripEqualityThroughJSON(for: UUIDCodingWrapper(uuid))
+            } catch let error {
+                XCTFail("\(error) for \(uuid)")
+            }
         }
     }
 

    
    func test_CharacterSet_JSON() {
        for characterSet in characterSetValues {
            XCTAssertTrue(expectRoundTripEqualityThroughJSON(for: characterSet))
        }
    }



    func test_Decimal_JSON() {
        for decimal in decimalValues {
            do {
                try expectRoundTripEqualityThroughJSON(for: decimal)
            } catch let error {
                XCTFail("\(error) for \(decimal)")
            }
        }
    }
    
