From 8a7dfa0972c83fd811a4296e7373574bea4a28d0 Mon Sep 17 00:00:00 2001 From: Nguyễn Gia Phong Date: Sun, 19 Jul 2020 20:34:40 +0700 Subject: [usth/ICT2.7] Remove Udacity transcribes --- ...8 - Black Box Testing Example - lang_en_vs4.srt | 135 --------------------- 1 file changed, 135 deletions(-) delete mode 100644 usth/ICT2.7/P4L1 General Concepts Subtitles/18 - Black Box Testing Example - lang_en_vs4.srt (limited to 'usth/ICT2.7/P4L1 General Concepts Subtitles/18 - Black Box Testing Example - lang_en_vs4.srt') diff --git a/usth/ICT2.7/P4L1 General Concepts Subtitles/18 - Black Box Testing Example - lang_en_vs4.srt b/usth/ICT2.7/P4L1 General Concepts Subtitles/18 - Black Box Testing Example - lang_en_vs4.srt deleted file mode 100644 index dab72eb..0000000 --- a/usth/ICT2.7/P4L1 General Concepts Subtitles/18 - Black Box Testing Example - lang_en_vs4.srt +++ /dev/null @@ -1,135 +0,0 @@ -1 -00:00:00,500 --> 00:00:03,185 -To give you a slightly better understanding of the differences - -2 -00:00:03,185 --> 00:00:06,300 -between black-box testing and white-box testing, I am going to provide you - -3 -00:00:06,300 --> 00:00:10,040 -a couple of simple examples that illustrate the, the strengths and - -4 -00:00:10,040 --> 00:00:12,920 -limitations of these two techniques. So, in this case, let's start - -5 -00:00:12,920 --> 00:00:15,750 -with black-box testing, so we're only working with this specification. - -6 -00:00:15,750 --> 00:00:18,540 -So, let's say that our specification says that this is a - -7 -00:00:18,540 --> 00:00:23,550 -program that inputs an integer value and prints it. And implementation, - -8 -00:00:23,550 --> 00:00:25,900 -we don't know because we're working at the black box level. - -9 -00:00:25,900 --> 00:00:28,710 -If we wanted to test this function according to its - -10 -00:00:28,710 --> 00:00:32,060 -specification, what we will probably do is to select a positive - -11 -00:00:32,060 --> 00:00:35,370 -integer, a negative integer, and the zero as test inputs - -12 -00:00:35,370 --> 00:00:37,840 -and see how the program behaves for these inputs. So let - -13 -00:00:37,840 --> 00:00:41,500 -me now show you a possible implementation for this specification. - -14 -00:00:41,500 --> 00:00:44,590 -What I'm showing here is this function that we called print - -15 -00:00:44,590 --> 00:00:48,010 -NumBytes, which takes the parameter and prints it. And one thing - -16 -00:00:48,010 --> 00:00:50,905 -that we notice right away is that, although in the specification, - -17 -00:00:50,905 --> 00:00:53,960 -numbers that are less than 1024 and numbers that - -18 -00:00:53,960 --> 00:00:57,320 -are greater or equal to 1024 are exactly equivalent from - -19 -00:00:57,320 --> 00:01:01,020 -the specification standpoint. They're however treated differently in the - -20 -00:01:01,020 --> 00:01:04,140 -code, so the developer decided that the program was just - -21 -00:01:04,140 --> 00:01:06,200 -going to print the value of the parameter if it's - -22 -00:01:06,200 --> 00:01:09,300 -less than 1024. But it was actually divided by 1024 - -23 -00:01:09,300 --> 00:01:13,560 -and printing it with a kilobyte mark after it - -24 -00:01:13,560 --> 00:01:16,170 -if you are greater than 1024. And notice that here, - -25 -00:01:16,170 --> 00:01:19,370 -there is a problem. The developer, just a number 124, instead - -26 -00:01:19,370 --> 00:01:22,840 -of 1024. So there's probably a typo in this point in the - -27 -00:01:22,840 --> 00:01:26,260 -code. So this is a case in which by simply doing black-box - -28 -00:01:26,260 --> 00:01:28,750 -testing, so by simply looking at the specific issue, we might miss - -29 -00:01:28,750 --> 00:01:31,510 -this problem. Because we have no reason to consider numbers that are - -30 -00:01:31,510 --> 00:01:34,780 -less than 1024 or greater than 1024. However if we were to - -31 -00:01:34,780 --> 00:01:38,010 -look at the code, so operating at white-box manner, we will right - -32 -00:01:38,010 --> 00:01:41,340 -away see that we need to have a test case that checks - -33 -00:01:41,340 --> 00:01:44,880 -the program when the parameter is greater than 1024. And we will find - -34 -00:01:44,880 --> 00:01:47,300 -the problem right away. So now let me show you a dual example. -- cgit 1.4.1