Deriving testcases
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This document discusses different techniques for deriving test cases, including: 1. An example of deriving test cases for an adder application by considering equivalence class partitioning and different input combinations. 2. Deriving test cases for a word to PDF publishing application by considering different document types, publishing options, locations, and compatibility scenarios. 3. The technique of combinatorial testing to derive a representative set of test cases by combining variations in multiple test parameters rather than testing all possible combinations.
Deriving testcases
- 1. Deriving Test Cases ‘ Software Quality – a myth or reality’ © Knowledge Tester
- 2. Deriving test cases • Software Testing looks interesting; let’s learn it : One skill that every Tester needs is ‘derive test cases for a specific feature’ • What is a Test case? • Exercise 1: Adder application • Equivalence class partition • Exercise 2: Doc to Pdf publishing • Combinatorial Testing • Bonus Exercise: Looking at the code © Knowledge Tester
- 3. What is a Test case? • A test case in software engineering is a set of conditions or variables under which a tester will determine whether an application or software system is working correctly or not. http://en.wikipedia.org/wiki/Test_case • Test case does have a corresponding with Use case. • Normally a test case has: –ID –Description –Input –Expected output. • A Test case either ‘passes’ or ‘fails’. • A Feature Test Plan is usually a set of Test cases. © Knowledge Tester
- 4. Exercise 1: Adder application Application: Adder application which takes two 2-digit no.s and displays the sum. ?2 ?3 5 ?_ Reference: 'Testing Computer Software' book by Cem Kaner, Jack Falk and Hung Q. Nguyen. © Knowledge Tester
- 5. Adder test cases 1 Test Case Inputs Result Notes 2+3 5 The basic test should pass first 99 + 99 198 Addition of 2 largest numbers -99 + -99 -198 Addition of 2 largest negative numbers 99 + 14 113 First number is largest -38 + 55 17 Mixing +ve and –ve numbers 56 + 99 155 Second number is largest 9+9 18 9 is the largest single digit number 0+0 0 0 is a special case 0 + 23 23 First number as 0 78 + 0 78 Second number as 0 © Knowledge Tester
- 6. Adder test cases 2 Test Case Inputs Notes 100 + 100 Beyond maximum number <Enter> + <Enter> What if we provide nothing? 12345678 + 0 Trying a very large number 1.2 + 5 Trying a decimal number A+b Trying not a number <Ctrl + A> + <F10> Trying special keys … © Knowledge Tester
- 7. Equivalence Class Partition The concept comes from Mathematics where we break Set into sub-sets based upon some criteria. Now assuming that one element from subset of a Set is equivalent to other member of same subset, we have one Test case represent one subset. © Knowledge Tester
- 8. Revisiting test cases • If we try 11+12, do we need to try 55+67? • Is 0 +9 and 9+0 belong to same subset or different subsets? • Are we missing some equivalence class? • When we move this concept to other data types, it becomes interesting. Say we want to try special characters in a string: is ‘test$’ same as ‘$test’ or ‘te$st’? © Knowledge Tester
- 9. Exercise 2: Word to PDF publishing © Knowledge Tester
- 10. PDF Publishing test cases 1 Test case Notes PDF can be generated with default Basic test options All pages can be published Page range options Current page can be published Page range options Pages range can be published Page range options Document with Markups can be published Different Mark ups / bookmarks Document Properties are available after Properties like Author name, Organization publishing name etc. PDF options are applicable What is ISO 19005-1? PDF is opened after publishing What if Adobe Reader is not installed? PDF can be published at any path Different type of directory selections © Knowledge Tester
- 11. PDF Publishing test cases 2 Test case Notes PDF optimization works Check for different file sizes Any File names can be provided Publishing to locations over network LAN, WAN Publishing older word documents Compatibility testing Office 2007/2003 Publishing huge word documents Performance testing Word drawings are published correctly Word specific data Embedded pictures are published Word specific data correctly Links in the word file are published Word specific data correctly … © Knowledge Tester
- 12. Combinatorial testing • What if we combine multiple options? • We try a set of pages publication with valid, invalid, long names? • Let’s take 3 variations: –Page range has 4 options. –Non-printing information has 4 options. –PDF options has 3. • Total possible set of tests are 4 x 4 x 3 = 48. • Should we run all 48 or some representative of these? • Further study: http://www.developsense.com/pairw iseTesting.html © Knowledge Tester