         } catch {
             XCTFail("Invalid Radix didn't throw correctly.")
         }
+        // Test 0 output from 0 input.
+        let zero = UInt128(0)
+        XCTAssert(zero.description == "0")
+        // Test String Conversion from UInt128 Input.
+        XCTAssertTrue(
+            try! UInt128(String(bizarreUInt128)) == bizarreUInt128,
+            "UInt128 Input to String Gave Incorrect Result"
+        )
     }
     func testBinaryStringConversion() {
         // String conversion test.

        }
    }
    func testHexadecimalStringConversion() {
        // Valid string conversion test.
        XCTAssertTrue(
            try! UInt128("0x001A111F111B1E1D111C11201110111015") == sanityValue,
            "Basic Hexadecimal String to UInt128 conversion failed"
        )
        // Invalid character.
        do {
            let _ = try UInt128("00g")
            XCTFail("Hexadecimal String with Invalid Character didn't throw.")
        } catch UInt128Errors.InvalidStringCharacter {
            XCTAssert(true)
        } catch {
            XCTFail("Hexadecimal String with Invalid Character didn't throw correctly.")
        }
        // Overflow.
        do {

        }
    }
    func testDecimalStringConversion() {
        // String input conversion test.
        XCTAssertTrue(
            try! UInt128("0034648827046971881013470724628828721173") == sanityValue,
            "Basic Decimal String to UInt128 conversion failed"
        )
        // Valid string output conversion test (lowercase)
        XCTAssertTrue(
            String(sanityValue, radix: 10, uppercase: false) == "34648827046971881013470724628828721173",
            "Basic UInt128 to Decimal Lowercase String Conversion Failed"
        )
        // Valid string output conversion test (uppercase)
        XCTAssertTrue(
            String(sanityValue, radix: 10, uppercase: true) == "34648827046971881013470724628828721173",
            "Basic UInt128 to Decimal Uppercase String Conversion Failed"
        )
        // Invalid character.
        do {
            let _ = try UInt128("00a")
