Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!us.feeder.erje.net!feeder.erje.net!eu.feeder.erje.net!eternal-september.org!feeder.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail
From: Eric Sosman <esosman@comcast-dot-net.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: in1To10, a simple test plan
Date: Sun, 10 Aug 2014 12:01:00 -0400
Organization: A noiseless patient Spider
Lines: 60
Message-ID: <ls84vs$eqb$1@dont-email.me>
References: <0c8de66a-429a-4697-b575-35f37a7b6882@googlegroups.com> <0rqdnVpuJ9ayDnrOnZ2dnUVZ8sKdnZ2d@bt.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=windows-1252; format=flowed
Content-Transfer-Encoding: 7bit
Injection-Date: Sun, 10 Aug 2014 16:01:00 +0000 (UTC)
Injection-Info: mx05.eternal-september.org; posting-host="bd4e1cba8d8592bec5d5ed9e4537fbfd"; logging-data="15179"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX1/rIorKDTGTmt6vqLN6KYV0"
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.0
In-Reply-To: <0rqdnVpuJ9ayDnrOnZ2dnUVZ8sKdnZ2d@bt.com>
Cancel-Lock: sha1:7ahLLc1hqwwEzMn0gVB6jywL/sk=
Xref: csiph.com comp.lang.java.programmer:29631

On 8/10/2014 11:43 AM, lipska the kat wrote:
> [...]
> public class In1To10 {
>
>     static boolean in1To10(int n, boolean outsideMode){
>        if(n == 1 || n == 10){
>           return true;
>        }
>        else{
>           return (n > 1 && n < 10) ^ outsideMode;
>        }
>     }
>
>     public static void main(String[] args){
>        boolean outsideMode = true;
>                                                     //Expected:  Actual:
>        System.out.println(in1To10(1, outsideMode));   //true    true
>        System.out.println(in1To10(1, !outsideMode));  //true    true
>        System.out.println(in1To10(10, outsideMode));  //true    true
>        System.out.println(in1To10(10, !outsideMode)); //true    true
>        System.out.println(in1To10(0, outsideMode));   //true    true
>        System.out.println(in1To10(0, !outsideMode));  //false    false
>        System.out .println(in1To10(-1, outsideMode)); //true    true
>        System.out.println(in1To10(-1, !outsideMode)); //false    false
>        System.out.println(in1To10(2, outsideMode));   //false    false
>        System.out.println(in1To10(2, !outsideMode));  //true    true
>        System.out.println(in1To10(5, outsideMode));   //false    false
>        System.out.println(in1To10(5, !outsideMode));  //true     true
>        System.out.println(in1To10(9, outsideMode));   //false    false
>        System.out.println(in1To10(9, !outsideMode));  //true     true
>        System.out.println(in1To10(11, outsideMode));  //true     true
>        System.out.println(in1To10(11, !outsideMode)); //false    false
>        //etc
>     }
> }

     While the notion of having a test plan is an excellent one, relying
on human eyeballs to verify the expected output is tedious and may be
error-prone.  I'd suggest writing a helper method, something like

	static void test(int number, boolean mode, boolean expected) {
	    boolean actual = in1To10(number, mode);
	    if (actual != expected) {
	        throw new AssertionError(String.format(
	            "in1To10(%d, %b) gave %b, expected %b",
	            number, mode, actual, expected);
	    }
	}

... and then write the test cases as

	test(1, true, true);
	test(1, false, true);
	...
	test(11, true, true);
	test(11, false, false);
	//etc

-- 
esosman@comcast-dot-net.invalid