Introduction to software testing potx

Introduction to software testing 2 Contents  Definitions, Principles, Axioms  Stages of testing  Perspectives on Software Testing  A little math (Part 1) 3 Definitions, Principles, Axioms 4 Definitions  Testing  Verification  Validation  Error/Defect  Black box testing  White box testing 5 Definitions of Testing (1)  The process of executing a program (or part of a program) with the intention of finding errors (Myers, Humphrey)  The purpose of testing is to find errors. Testing is the process of trying to discover every conceivable fault or weakness in a work product (Myers, Kit)  The process of searching for errors (Kaner) 6 Definitions of Testing (2)  Testing – the process of finding errors and of validating the program/system (Jorgensen)  The purpose of software testing is to find errors and to get them fixed (Bitzenhofer)  The purpose of software testing is to reduce risk (E&M) 7 Verification and Validation: Myers  Verification: An attempt to find errors by executing a program in a test or simulated environment  Validation: An attempt to find errors by executing a program in a real environment 8 Verification and Validation: IEEE  Verification: The process of evaluating a system or component to determine whether the products…satisfy the conditions imposed…  Validation: The process of evaluating a system or component…to determine whether it satisfies specified requirements. 9 Verification and Validation: Kaner  Verification: Checking a program against the most closely related design documents or specifications (“Design Verification Testing”)  Validation: Checking the program against the published user or system requirements (“System Validation Testing”) 10 Software Fault Terminology  Error – a mistake in design, coding, requirements, even testing  Fault (defect) – the representation of the error  Failure – what happens when the fault “executes” [...]... the test effort 2.Prevent defect migration by using early lifecycle testing techniques 3.The time for software testing tools is now Adapted from Software Testing in the Real World, Edward Kit; AddisonWesley, 1995 13 Six Essentials of Software Testing (2) 4.A real person must take responsibility for improving the testing process 5 .Testing is a professional discipline requiring trained, skilled people... destruction Adapted from Software Testing in the Real World, Edward Kit; AddisonWesley, 1995 14 Some Principles and Axioms of Testing (1)    “Program testing can be used to show the presence of bugs, but never their absence.” (Dijkstra, 1969) One of the most difficult problems in testing is knowing when to stop It is impossible to test your own program 15 Some Principles and Axioms of Testing (2)   ... parameter 11 Black and White Box  Black box testing     Designed without knowledge of the program‟s internal structure and design Based on functional requirements Also called Functional Testing White box testing    Examines the internal design of the program Requires detailed knowledge of its structure Also called Structural Testing 12 Six Essentials of Software Testing (1) 1.The quality of the test... Main, Regression, Acceptance Customer Acceptance Test 19 Unit Test     Performed by the developers White-box testing Should be done with each release to testing Results should be communicated to the Test Group 20 Typical Entry Criteria (Unit Test)     Module compiles successfully (no errors, approved warnings) Unit Test Plan complete Unit Test Cases complete Tools are available 21 Typical Unit... defects to the code and to the tests 28 Interface Testing     How does a user interact with the program? What input variables are required? What outputs are produced? Extremely important for e-business applications 29 Integration Testing      Integration between software components Integration with the front-end GUIs Integration between a server and its clients Integration between software. .. been stored under Configuration Management 23 Software Test Stages   Unit Test Design Verification Test   System Validation Test   Interface, Integration, Exit/Formal Test Phase Main, Regression, Acceptance Customer Acceptance Test 24 Design Verification Test (DVT)     Performed by the test organization Black box testing Verification of engineering requirements Verification of the software. .. defects in a piece of software increases, the probability of the existence of more undetected defects also increases Testing is an extremely creative and intellectually challenging task” (Myers again) Exhaustive testing is impossible 16 Stages of testing 17 The Test Process      Requirements phase Planning phase Design and development phase Execution phase Reporting phase 18 Software Test Execution.. .Software Fault Terminology: Examples  Error  A wrong loop index  Programmer -to- device pointer error  Fault – the representation of the error  A loop executes one too many times  A programmed parameter gets written to the wrong address  Failure – what happens when the fault “executes”  A table overflows;... successfully High severity defects have been fixed and verified 32 Software Test Stages   Unit Test Design Verification Test   System Validation Test   Interface, Integration, Exit/Formal Main, Regression, Acceptance Customer Acceptance Test 33 System Validation Test (SVT)    Performed by the test organization Validation of customer requirements Three components    Main Test Regression Test... install works 35 SVT Main Test      Verify the functional requirements of the product from the Customer‟s point of view Includes usability, reliability, performance, and installation Also has its own Entry and Exit criteria Use Cases form a big part of this testing Marketing issues are addressed here too 36 . Introduction to software testing 2 Contents  Definitions, Principles, Axioms  Stages of testing  Perspectives on Software Testing  A little math (Part 1) 3 Definitions,. techniques. 3.The time for software testing tools is now. Adapted from Software Testing in the Real World, Edward Kit; Addison- Wesley, 1995 14 Six Essentials of Software Testing (2) 4.A real person. (Kaner) 6 Definitions of Testing (2)  Testing – the process of finding errors and of validating the program/system (Jorgensen)  The purpose of software testing is to find errors and to get them fixed