Friday, 30 November 2007

Basic Test Case Concepts

A testcase is simply a test with formal steps and instructions; testcases are valuable because they are repeatable, reproducible under the same environments, and easy to improve upon with feedback. A testcase is the difference between saying that something seems to be working okay and proving that a set of specific tasks are known to be working correctly.

Some tests are more straightforward than others. For example, say you need to verify that all the links in your web site work. There are several different approaches to checking this:

you can read your HTML code to see that all the link code is correct
you can run an HTML DTD validator to see that all of your HTML syntax is correct, which would imply that your links are correct
you can use your browser (or even multiple browsers) to check every link manually
you can use a link-checking program to check every link automatically
you can use a site maintenance program that will display graphically the relationships between pages on your site, including links good and bad
you could use all of these approaches to test for any possible failures or inconsistencies in the tests themselves
Verifying that your site's links are not broken is relatively unambiguous. You simply need to decide which one of more of these tests best suits your site structure, your test resources, and your need for granularity of results. You run the test, and you get your results showing any broken links.

Notice that you now have a list of broken links, not of incorrect links. If a link is valid syntactically, but points at the incorrect page, your link test won't catch the problem. My general point here is that you must understand what you are testing. A testcase is a series of explicit actions and examinations that identifies the "what".

A testcase for checking links might specify that each link is tested for functionality, appropriateness, usability, style, consistency, etc. For example, a testcase for checking links on a typical page of a site might include these steps:
Link Test: for each link on the page, verify that

the link works (i.e., it is not broken)
the link points at the correct page
the link text effectively and unambiguously describes the target page
the link follows the approved style guide for this web site (for example, closing punctuation is or is not included in the link text, as per the style guide specification)
every instance of a link to the same target page is coded the same way.

As you can see, this is a detailed testing of many aspects of the link, with the result that on completion of the test, you can say definitively what you know works. However, this is a simple example: testcases can run to hundreds of instructions, depending on the types of functionality being tested and the need for iterations ofsteps.

Defining Test and Testcase Parameters
A testcase should set up any special environment requirements the test may have, such as clearing the browser cache, enabling JavaScript support, or turning on the warnings for the dropping of cookies.
In addition to specific configuration instructions, testcases should also record browser types and versions, operating system, machine platforms, connection speeds -- in short, the testcase should record any parameter that would affect the reproducibility of the results or could aid in troubleshooting any defects found by testing. Or to state this a little differently, specify what platforms this testcase should be run against, record what platforms it is run against, and in the case of defects report the exact environment in which the defect was found. The various required fields of a test case are as follows

Test Case ID: It is unique number given to test case in order to be identified.

Test description: The description if test case you are going to test.

Revision history: Each test case has to have its revision history in order to know when and by whom it is created or modified.

Function to be tested: The name of function to be tested.

Environment: It tells in which environment you are testing.

Test Setup: Anything you need to set up outside of your application for example printers, network and so on.

Test Execution: It is detailed description of every step of execution.

Expected Results: The description of what you expect the function to do.

Actual Results: pass / failed If pass - What actually happen when you run the test. If failed - put in description of what you've observed.

Sample Testcase
Here is a simple test case for applying bold formatting to a text.

Test case ID: B 001
Test Description: verify B - bold formatting to the text
Revision History:
3/ 23/ 00 1.0- Valerie- Created
Function to be tested: B - bold formatting to the text
Environment: Win 98
Test setup: N/A
Test Execution:

Open program
Open new document
Type any text
Select the text to make bold.
Click Bold

Expected Result: Applies bold formatting to the text
Actual Result: pass

Testcase definition
Define testcases in the Definition pane of the Component Test perspective. This is also where you define the hosts on which the testcases will run. Once you define the testcase element in the Definition pane, its contents appear in the Outline pane. You can add elements to the testcase's main block, and once your definition is complete you can prepare it to run and create a testcase instance.

Testcase stages
As you work with testcases in the Component Test perspective, they go through different stages, from definition to analysis. Each stage is generated from the previous one, but is otherwise unrelated: for example, although a testcase instance is generated from a testcase definition, changes to the definition will not affect the instance

Creating manual testcases
Create manual testcases to guide a tester through the steps necessary to test a component or application. Once you have created a manual testcase, you can prepare it to run.

Adding manual testcases
To add a manual testcase to the Component Test perspective, follow these steps:
1.In the Definition pane, right-click on Testcases and click: New > Testcase
2.In the New Testcase wizard, select the project you want to define the testcase in.
3.Name the project and click Next.
4.Select the Manual scheduler.
5.Click Finish to add the testcase to the Testcase folder under the selected project.
The contents of the testcase appear in the Outline pane. To start with, it contains a main block, which will organize all the other contents of the testcase.

Creating HTTP testcases
Create HTTP testcases to run methods and queries against an HTTP server. You can define HTTP testcases by importing an HTTP XML file that defines a set of interactions, or you can define it using the tasks below. Once you have defined the testcase, you can prepare it to run.
Creating Java testcases
Create Java testcases to test static Java methods by calling them and verifying the results. Once you have defined the testcase, you can generate an instance of it, and edit the instance's code to provide the logic for evaluating each task and verification point.

Adding Java testcases
To add a Java testcase to the Component Test perspective:
1.In the Definition pane, right-click on Testcases and click: New > Testcase
2.In the New Testcase wizard, select the project you want to define the testcase in.
3.Name the project and click Next.
4.Select the Java scheduler.
5.Click Finish to add the testcase to the Testcase folder under the selected project.
The contents of the testcase appear in the Outline pane. To start with, it contains a main block, which will organize all the other contents of the testcase.

Reusing testcases
You can reuse existing testcase definitions when you define new ones. This lets you define testcases for common sequences (such as logging into an application) that you can then reuse in more complex compound testcases.
To reuse a testcase:
1.Select the testcase you want to add the existing testcase to.
2.In the Outline pane, right-click the block you want to add the testcase to and click Add Testcase Definition Reference.
3.In the Add Testcase Definition Reference wizard, select the testcase you want to reuse.
4.Click Finish.
The reused testcase is incorporated by reference: its definition is still maintained separately, and the compound testcase definition will pick up changes to the testcases it reuses. However, when you create a testcase instance, the generated code for the referenced testcase definition will be stored as part of the referencing testcase instance. In other words, reuse happens only at the definition level: at the instance level, each reusing testcase creates its own copy of the reused testcases.

Test Cases & Explanation
We will not supply you with test input for most of your assignments. Part of your job will be to select input cases to show that your program works correctly. You should select input from the following categories:

Normal Test Cases: These are inputs that would be considered "normal" or "average" for your program. For example, if your program computes square roots, you could try several positive numbers, both less than and greater than 1, including some perfect squares such as 16 and some numbers without rational square roots.

Boundary Test Cases: These are inputs that are legal, but on or near the boundary between legal and illegal values. For example, in a square root program, you should try 0 as a boundary cases.

Exception Test Cases: These are inputs that are illegal. Your program may give an error message or it might crash. In a square root program, negative numbers would be exception test cases.

You must hand in outputs (saved in file form) of your test runs. In addition to handing in your actual test runs, give us a quick explanation of how you picked them. For example, if you write a program to compute square roots, you might say "my test input included zero, small and large positive numbers, perfect squares and numbers without a rational square root, and a negative number to demonstrate error handling". You may give this explanation in the separate README file, or included alongside the test cases.

You will be marked for how well the test cases you pick demonstrate that your program works correctly. If your program doesn't work correctly in all cases, please be honest about it. It is perfectly valid to have test cases which illustrate the circumstances in which your program does not yet work. If your program doesn't run at all, you can hand in a set of test cases with an explanation of how you picked them and what the correct output would be. Both of these will get you full marks for testing. If you pick test cases to hide the faults in your program, you will lose marks.

Black Box Test Case Design
Objective and Purpose
The purpose of the Black Box Test Case Design (BBTD) is to discover circumstances under which the assessed object will not react and behave according to the requirements or respectively the specifications.
Operational Sequence
The test cases in a black box test case design are deviated from the requirements or respectively the specifications. The object to be assessed is considered as a black box, i. e. the assessor is not interested in the internal structure and the behavior of the object to be assessed.

It can be differentiated between the following black box test case designs:
>Generation of equivalence classes
>Marginal value analysis
>Intuitive test case definition
>Function coverage

1. Generation of Equivalence Classes :
Objective and Purpose :
It is the objective of the generation of equivalence classes to achieve an optional probability to detect errors with a minimum number of test cases.
Operational Sequence :The principle of the generation of equivalence classes is to group all input data of a program into a finite number of equivalence classes so it can be assumed that with any representative of a class it is possible to detect the same errors as with any other representative of this class.
The definition of test cases via equivalence classes is realized by means of the following steps:
Analysis of the input data requirements, the output data requirements, and the conditions according to the specifications

2. Definition of the equivalence classes by setting up the ranges for input and output data

3. Definition of the test cases by means of selecting values for each classwhen defining equivalence classes, two groups of equivalence classes have to be differentiated:
valid equivalence classes
invalid equivalence classes For valid equivalence classes, the valid input data are selected; in case of invalid equivalence classes erroneous input data are selected. If the specification is available, the definition of equivalence classes is predominantly a heuristic process.

4. Marginal Value Analysis :
Objective and Purpose :
It is the objective of the marginal value analysis to define test cases that can be used to discover errors connected with the handling of range margins.
Operational Sequence :
The principle of the marginal value analysis is to consider the range margins in connection with the definition of test cases. This analysis is based on the equivalence classes defined by means of the generation of equivalence classes. Contrary to the generation of equivalence classes, not any one representative of the class is selected as test case but only the representatives at the class margins. Therefore, the marginal value analysis represents an addition to the test case design according to the generation of equivalence classes.

5. Intuitive Test Case Definition
Objective and Purpose :
It is the objective of the intuitive test case definition to improve systematically detected test cases qualitatively, and also to detect supplementary test cases.
Operational Sequence :
Basis for this methodical approach is the intuitive ability and experience of human beings to select test cases according to expected errors. A regulated procedure does not exist. Apart from the analysis of the requirements and the systematically defined test cases (if realized) it is most practical to generate a list of possible errors and error-prone situations. In this connection it is possible to make use of the experience with repeatedly occurred standard errors. Based on these identified errors and critical situations the additional test cases will then be defined.

6. Function Coverage Objective and Purpose
It is the purpose of the function coverage to identify test cases that can be used to proof that the corresponding function is available and can be executed as well. In this connection the test case concentrates on the normal behavior and the exceptional behavior of the object to be assessed.
Operational Sequence
Based on the defined requirements, the functions to be tested must be identified. Then the test cases for the identified functions can be defined.
Recommendation
With the help of a test case matrix it is possible to check if functions are covered by several test cases. In order to improve the efficiency of the tests, redundant test cases ought to be deleted.

White Box Test Case Design
Objective and Purpose
The objective of the "White Box Test Case Design" (WBTD) is to detect errors by means of execution-oriented test cases.
Operational Sequence
White Box Testing is a test strategy which investigates the internal structure of the object to be assessed in order to specify execution-oriented test cases on the basis of the program logic. In this connection the specifications have to be taken into consideration, though. In a test case design, the portion of the assessed object which is addressed by the test cases is taken into consideration. The considered aspect may be a path, a statement, a branch, and a condition. The test cases are selected in such a manner that the correspondingly addressed portion of the assessed object is increased.

The following White Box Test Case methods exist:
1. Path coverage
2. Statement coverage
3. Branch coverage
4. Condition coverage
5. Branch/condition coverage
6. Coverage of all multiple conditions

1.Path Coverage
Objective and Purpose
It is the objective of the path coverage to identify test cases executing a required minimum number of paths in the object to be assessed. The execution of all paths cannot be realized as a rule.
Operational Sequence
By taking into consideration the specification, the paths to be executed and the corresponding test cases will be defined.

2. Statement Coverage
Objective and Purpose
It is the objective of the statement coverage to identify test cases executing a required minimum number of statements in the object to be assessed.
Operational Sequence
By taking into consideration the specification, statements are identified and the corresponding test cases are defined. Depending on the required coverage degree, either all or only a certain number of statements are to be used for the test case definition.

3. Branch Coverage
Objective and Purpose
It is the objective of the branch coverage to identify test cases executing a required minimum number of branches, i. e. at least once in the object to be assessed.
Operational Sequence
By taking into consideration the specification, a sufficiently large number of test cases must be designed by means of an analysis so both the THEN and the ELSE branch are executed at least once for each decision. I. e. the exit for the fulfilled condition and the exit for the unfulfilled must be utilized and each entry must be addressed at least once. For multiple decisions there exists the additional requirement to test each possible exit at least once and to address each entry at least once.

4. Condition Coverage
Objective and Purpose
The objective of the condition coverage is to identify test cases executing a required minimum number of conditions in the object to be assessed.
Operational Sequence
By taking into consideration the specification, conditions are identified and the corresponding test cases are defined. The test cases are defined on the basis of a path sequence analysis.

5. Branch/Condition Coverage
Objective and Purpose
The objective of the branch/condition coverage is to identify test cases executing a required minimum number of branches and conditions in the object to be assessed.
Operational Sequence
By taking into consideration the specification, branches and conditions are identified and the corresponding test cases are defined.

6. Coverage of all Multiple Conditions
Objective and Purpose
The objective of the coverage of all multiple conditions is to identify test cases executing a required minimum number of all possible condition combinations for a decision in the object to be assessed.
Operational Sequence
By taking into consideration the specification, condition combinations for decisions are identified and the corresponding test cases are defined. When defining test cases it must be observed that all entries are addressed at least once.

Test Cases :::::

How to write TEST CASES?
To write test cases one should be clear on the specifications required for a particular case. Once the case is decided check out for the requirments and then write test cases. For writing test cases first you must find Boundary Value Analysis. Let us write a test case for a Consignee Details Form. (Consignee Details : Consignee is the customer whoever to purchase our product. Here he want to give the information about himself. For example name, address and etc...)

Here is the screen shot of the form


Software Requirement Specification
According to the software requirement specification (SRS) one should write test cases upto expected results.

Here is the screen shot of SRS

Boundary Value Analysis:
It concentrate on range between minimum value and maximum values. It does not concentrate on centre values.

For example how to calculate Boundary Value for Company name field

Minimum length is 4 & Maximum length is 15

For Boundary value you have to check + or – minimum length and + or – Maximum length
for Company name field minimum value =3,4,5
maximum value=14,15,16

According to the Software Requirement Specification
The boundary values given above are

Valid values=4,5,14,15
Invalid values=3,16 because this values are out of range where as given in software requirement specification.




>You have to write test cases for Boundary values also.
For single user id field you have 11 test case including boundary value.
>You have to write test cases upto expected result after getting software requirement specification itself you can start writing a test cases.
>After the creation of test cases completed.
>Arrival of build will be arises to the testing field
>Build->Its a complete project
>After that you have to execute the test cases

EXECUTION OF TEST CASES
You have to check all the possible Test input given in test cases and then check whether all the test cases are executed or not

How to execute?>For example
whether you are checking company name as a mandatory means
you need not give any input to Company name field and then enter password .then click OK button means.
That alert message “Enter Company name:” must be displayed. This was your expected result . If it is happen while you are executing the test cases with the project .
Mandatory->compulsory

Test Case 1
Test Case ID : Test Case Title
The test case ID may be any convenient identifier, as decided upon by the tester. Identifiers should follow a consistent pattern within Test cases, and a similar consistency should apply access Test Modules written for the same project.



Purpose:
The purpose of the Test case, usually to verify a specific requirement.

Owner:
The persons or department responsible for keeping the Test cases accurate.

Expected Result :
Describe the expected results and outputs from this Test Case. It is also desirable to include some method of recording whether or not the expected results actually occurred (i.e.) if the test case, or even individual steps of the test case, passed.

Test Data:
Any required data input for the Test Case.

Test Tools:
Any specific or unusual tools or utilities required for the execution of this Test Case.

Dependencies :
If correct execution of this Test Case depends on being pleceded by any other Test Cases, that fact should be mentioned here. Similarly any dependency on factory outside the immediate test environment should also be mentioned.

Initialization :
If the system software or hardware has to be initialized in a particular manner in order for this Test case to succeed, such initialization should be mentioned here.

Description:
Describe what will take place during the Test Case the description should take the form of a narrative description of the Test Case, along with a Test procedure , which in turn can be specified by test case steps, tables of values or configurations, further narrative or whatever is most appropriate to the type of testing taking place.

Test Case 2


Test Case 3

Test case 4

Test Case Description : Identify the Items or features to be tested by this test case.

Pre and post conditions: Description of changes (if any) to be standard environment. Any modification should be automatically done.

Test Case 4 - Description

Case : Test Case Name

Component : Component Name

Author : Developer Name

Date : MM – DD – YY

Version : Version Number

Input / Output Specifications:
Identify all inputs / Outputs required to execute the test case. Be sure to identify all required inputs / outputs not just data elements and values:

> Data (Values , ranges, sets )
> Conditions (States: initial, intermediate, final)
> Files (database, control files)

Test Procedure
Identify any special constrains on the test case. Focus on key elements such as special setup.

Expected Results
Fill this row with the description of the test results

Failure Recovery
Explanations regarding which actions should be performed in case of test failure.

Comments
Suggestions, description of possible improvements, etc.

Test Case 5




WEB TESTING

Writing Test Cases for Web Browsers

This is a guide to making test cases for Web browsers, for example making test cases to show HTML, CSS, SVG, DOM, or JS bugs. There are always exceptions to all the rules when making test cases. The most important thing is to show the bug without distractions. This isn't something that can be done just by following some steps, you have to be intelligent about it. Minimising existing testcases.

STEP ONE: FINDING A BUG
The first step to making a testcase is finding a bug in the first place. There are four ways of doing this:
1. Letting someone else do it for you: Most of the time, the testcases you write will be for bugs that other people have filed. In those cases, you will typically have a Web page which renders incorrectly, either a demo page or an actual Web site. However, it is also possible that the bug report will have no problem page listed, just a problem description.
2. Alternatively, you can find a bug yourself while browsing the Web. In such cases, you will have a Web site that renders incorrectly.
3. You could also find the bug because one of the existing testcases fails. In this case, you have a Web page that renders incorrectly.
4. Finally, the bug may be hypothetical: you might be writing a test suite for a feature without knowing if the feature is broken or not, with the intention of finding bugs in the implementation of that feature. In this case you do not have a Web page, just an idea of what a problem could be.

If you have a Web page showing a problem, move to the next step. Otherwise, you will have to create an initial testcase yourself. This is covered on the section on "Creating testcases from scratch" later.

STEP TWO: REMOVING DEPENDENCIES
You have a page that renders incorrectly.
Make a copy of this page and all the files it uses, and update the links so they all point to the copies you made of the files. Make sure that it still renders incorrectly in the same way -- if it doesn't, find out why not. Make your copy of the original files as close to possible as the original environment, as close as needed to reproduce the bug. For example, instead of loading the files locally, put the files on a remote server and try it from there. Make sure the MIME types are the same if they need to be, etc.
Once you have your page and its dependencies all set up and still showing the same problem, embed the dependencies one by one.
For example, change markup like this:
link rel="stylesheet" href="foo.css"
...to this:

Each time you do this, check that you haven't broken any relative URIs and that the page still shows the problem. If the page stops showing the problem, you either made a mistake when embedding the external files, or you found a bug specifically related to the way that particular file was linked. Move on to the next file.

STEP THREE: MAKING THE TEST FILE SMALLER
Once you have put as many of the external dependencies into the test file as you can, start cutting the file down.
Go to the middle of the file. Delete everything from the middle of the file to the end. (Don't pay attention to whether the file is still valid or not.) Check that the error still occurs. If it doesn't, put that part pack, and remove the top half instead, or a smaller part.
Continue in this vein until you have removed almost all the file and are left with 20 or fewer lines of markup, or at least, the smallest amount that you need to reproduce the problem.
Now, start being intelligent. Look at the file. Remove bits that clearly will have no effect on the bug. For example if the bug is that the text "investments are good" is red but should be green, replace the text with just "test" and check it is still the wrong colour.
Remove any scripts. If the scripts are needed, try doing what the scripts do then removing them -- for example, replace this:
;
..with:

test


...and check that the bug still occurs.
Merge any < style > blocks together.
Change presentational markup for CSS. For example, change this:
< font color="red" >
...to:
span { color: red; } /* in the stylesheet */

Do the same with style="" attributes (remove the attributes, but it in a < style > block instead).
Remove any classes, and use element names instead. For example: .
.a { color: red; }
.b { color: green; }

This should be green.


...becomes:
div { color: red; }
p { color: green; }

This should be green.


Do the same with IDs. Make sure there is a strict mode DOCTYPE:

Remove any< meta >elements. Remove any "lang" attributes or anything that isn't needed to show the bug.
If you have images, replace them with very simple images, e.g.:
http://hixie.ch/resources/images/sample
If there is script that is required, remove as many functions as possible, merge functions together, put them inline instead of in functions.

STEP FOUR: GIVE THE TEST AN OBVIOUS PASS CONDITION
The final step is to make sure that the test can be used quickly. It must be possible to look at a test and determine if it has passed or failed within about 2 seconds.
There are many tricks to do this, which are covered in other documents such as the CSS2.1 Test Case Authoring
Guidelines:
http://www.w3.org/Style/CSS/Test/guidelines.html
Make sure your test looks like it has failed even if no script runs or anything. Make sure the test doesn't look blank if it fails.

Creating testcases from scratch

STEP ONE: FIND SOMETHING TO TEST

Read the relevant specification.
Read it again.
Read it again, making sure you read every last bit of it, cover to cover.
Read it one more time, this time checking all the cross-references.
Read the specification in random order, making sure you understand every last bit of it.
Now, find a bit you think is likely to be implemented wrongly.
Work out a way in which a page could be created so that if the browser gets it right, the page will look like the test has passed, and if the browser gets it wrong, the page will look like it failed.
Write that page.
Now jump to step four above.

Note:
This information is collected.

7 comments:

Anonymous said...

The article is really helpful!!!

Regards,
Rakesh

Unknown said...

This blog is really helpful.
Let me know what type of testcase comes under security testcase e.g authentication testing for log in.
I need detail information about it(Web base application)

jai said...

very nice article..
very helpful for beginners..
jai

jai said...

very nice article..
it is very useful for beginners like me...
jai

Unknown said...

Hi,

I recently came across your blog and have been reading along. I thought I would leave my first comment. I don't know what to say except that I have enjoyed reading.

Nice blog. I will keep visiting this blog very often.

-
Delphi development

Anonymous said...

this really useful stuff in the testing.

http://soft-engineering.blogspot.com/

Article Submissions said...

Excellent article. This explained the process clearly. I've been reading your other articles as well and have found them very useful as I study for my iseb.