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Friday, September 4, 2009

Software QA and Testing Frequently-Asked-Questions

What makes a good Software Test engineer?
A good test engineer has a 'test to break' attitude, an ability to take the point of view of the customer, a strong desire for quality, and an attention to detail. Tact and diplomacy are useful in maintaining a cooperative relationship with developers, and an ability to communicate with both technical (developers) and non-technical (customers, management) people is useful. Previous software development experience can be helpful as it provides a deeper understanding of the software development process, gives the tester an appreciation for the developers' point of view, and reduce the learning curve in automated test tool programming. Judgement skills are needed to assess high-risk or critical areas of an application on which to focus testing efforts when time is limited.

What makes a good Software QA engineer?
The same qualities a good tester has are useful for a QA engineer. Additionally, they must be able to understand the entire software development process and how it can fit into the business approach and goals of the organization. Communication skills and the ability to understand various sides of issues are important. In organizations in the early stages of implementing QA processes, patience and diplomacy are especially needed. An ability to find problems as well as to see 'what's missing' is important for inspections and reviews.

What makes a good QA or Test manager?
A good QA, test, or QA/Test(combined) manager should:

  • be familiar with the software development process
  • be able to maintain enthusiasm of their team and promote a positive atmosphere, despite what is a somewhat 'negative' process (e.g., looking for or preventing problems)
  • be able to promote teamwork to increase productivity
  • be able to promote cooperation between software, test, and QA engineers
  • have the diplomatic skills needed to promote improvements in QA processes
  • have the ability to withstand pressures and say 'no' to other managers when quality is insufficient or QA processes are not being adhered to
  • have people judgement skills for hiring and keeping skilled personnel
  • be able to communicate with technical and non-technical people, engineers, managers, and customers.
  • be able to run meetings and keep them focused

What's the role of documentation in QA?
Generally, the larger the team/organization, the more useful it will be to stress documentation, in order to manage and communicate more efficiently. (Note that documentation may be electronic, not necessarily in printable form, and may be embedded in code comments, may be embodied in well-written test cases, user stories, etc.) QA practices may be documented to enhance their repeatability. Specifications, designs, business rules, configurations, code changes, test plans, test cases, bug reports, user manuals, etc. may be documented in some form. There would ideally be a system for easily finding and obtaining information and determining what documentation will have a particular piece of information. Change management for documentation can be used where appropriate. For agile software projects, it should be kept in mind that one of the agile values is "Working software over comprehensive documentation", which does not mean 'no' documentation. Agile projects tend to stress the short term view of project needs; documentation often becomes more important in a project's long-term context.

What's the big deal about 'requirements'?
One of the most reliable methods of ensuring problems, or failure, in a large, complex software project is to have poorly documented requirements specifications. (Note that requirements documentation can be electronic, not necessarily in the form of printable documents, and may be embedded in code comments, may be embodied in well-written test cases, etc.) Requirements are the details describing an application's externally-perceived functionality and properties. Requirements should be clear, complete, reasonably detailed, cohesive, attainable, and testable. A non-testable requirement would be, for example, 'user-friendly' (too subjective). A more testable requirement would be something like 'the user must enter their previously-assigned password to access the application'. Determining and organizing requirements details in a useful and efficient way can be a difficult effort; different methods are available depending on the particular project. Many books are available that describe various approaches to this task. (See the section's 'Software Requirements Engineering' category for books on Software Requirements.)

Care should be taken to involve ALL of a project's significant 'customers' in the requirements process. 'Customers' could be in-house personnel or outside personnel, and could include end-users, customer acceptance testers, customer contract officers, customer management, future software maintenance engineers, salespeople, etc. Anyone who could later derail the project if their expectations aren't met should be included if possible.

Organizations vary considerably in their handling of requirements specifications. Often the requirements are spelled out in a document with statements such as 'The product shall.....'. 'Design' specifications should not be confused with 'requirements'; design specifications are ideally traceable back to the requirements.

In some organizations requirements may end up in high level project plans, functional specification documents, in design documents, or in other documents at various levels of detail. No matter what they are called, some type of documentation with detailed requirements will be needed by testers in order to properly plan and execute tests. Without such documentation, there will be no clear-cut way to determine if a software application is performing correctly.

'Agile' approaches use methods requiring close interaction and cooperation between programmers and customers/end-users to iteratively develop requirements, user stories, etc. In the XP 'test first' approach developers create automated unit testing code before the application code, and these automated unit tests essentially embody the requirements.

What steps are needed to develop and run software tests?
The following are some of the steps to consider:

  • Obtain requirements, functional design, and internal design specifications, user stories, and other available/necessary information
  • Obtain budget and schedule requirements
  • Determine project-related personnel and their responsibilities, reporting requirements, required standards and processes (such as release processes, change processes, etc.)
  • Determine project context, relative to the existing quality culture of the product/organization/business, and how it might impact testing scope, aproaches, and methods.
  • Identify application's higher-risk and mor important aspects, set priorities, and determine scope and limitations of tests.
  • Determine test approaches and methods - unit, integration, functional, system, security, load, usability tests, etc.
  • Determine test environment requirements (hardware, software, configuration, versions, communications, etc.)
  • Determine testware requirements (automation tools, coverage analyzers, test tracking, problem/bug tracking, etc.)
  • Determine test input data requirements
  • Identify tasks, those responsible for tasks, and labor requirements
  • Set schedule estimates, timelines, milestones
  • Determine, where apprapriate, input equivalence classes, boundary value analyses, error classes
  • Prepare test plan document(s) and have needed reviews/approvals
  • Write test cases
  • Have needed reviews/inspections/approvals of test cases
  • Prepare test environment and testware, obtain needed user manuals/reference documents/configuration guides/installation guides, set up test tracking processes, set up logging and archiving processes, set up or obtain test input data
  • Obtain and install software releases
  • Perform tests
  • Evaluate and report results
  • Track problems/bugs and fixes
  • Retest as needed
  • Maintain and update test plans, test cases, test environment, and testware through life cycle

What's a 'test plan'?
A software project test plan is a document that describes the objectives, scope, approach, and focus of a software testing effort. The process of preparing a test plan is a useful way to think through the efforts needed to validate the acceptability of a software product. The completed document will help people outside the test group understand the 'why' and 'how' of product validation. It should be thorough enough to be useful but not so thorough that no one outside the test group will read it. The following are some of the items that might be included in a test plan, depending on the particular project:

  • Title
  • Identification of software including version/release numbers
  • Revision history of document including authors, dates, approvals
  • Table of Contents
  • Purpose of document, intended audience
  • Objective of testing effort
  • Software product overview
  • Relevant related document list, such as requirements, design documents, other test plans, etc.
  • Relevant standards or legal requirements
  • Traceability requirements
  • Relevant naming conventions and identifier conventions
  • Overall software project organization and personnel/contact-info/responsibilties
  • Test organization and personnel/contact-info/responsibilities
  • Assumptions and dependencies
  • Project risk analysis
  • Testing priorities and focus
  • Scope and limitations of testing
  • Test outline - a decomposition of the test approach by test type, feature, functionality, process, system, module, etc. as applicable
  • Outline of data input equivalence classes, boundary value analysis, error classes
  • Test environment - hardware, operating systems, other required software, data configurations, interfaces to other systems
  • Test environment validity analysis - differences between the test and production systems and their impact on test validity.
  • Test environment setup and configuration issues
  • Software migration processes
  • Software CM processes
  • Test data setup requirements
  • Database setup requirements
  • Outline of system-logging/error-logging/other capabilities, and tools such as screen capture software, that will be used to help describe and report bugs
  • Discussion of any specialized software or hardware tools that will be used by testers to help track the cause or source of bugs
  • Test automation - justification and overview
  • Test tools to be used, including versions, patches, etc.
  • Test script/test code maintenance processes and version control
  • Problem tracking and resolution - tools and processes
  • Project test metrics to be used
  • Reporting requirements and testing deliverables
  • Software entrance and exit criteria
  • Initial sanity testing period and criteria
  • Test suspension and restart criteria
  • Personnel allocation
  • Personnel pre-training needs
  • Test site/location
  • Outside test organizations to be utilized and their purpose, responsibilties, deliverables, contact persons, and coordination issues
  • Relevant proprietary, classified, security, and licensing issues.
  • Open issues
  • Appendix - glossary, acronyms, etc.

What's a 'test case'?
A test case describes an input, action, or event and an expected response, to determine if a feature of a software application is working correctly. A test case may contain particulars such as test case identifier, test case name, objective, test conditions/setup, input data requirements, steps, and expected results. The level of detail may vary significantly depending on the organization and project context.

Note that the process of developing test cases can help find problems in the requirements or design of an application, since it requires completely thinking through the operation of the application. For this reason, it's useful to prepare test cases early in the development cycle if possible.

What should be done after a bug is found?
The bug needs to be communicated and assigned to developers that can fix it. After the problem is resolved, fixes should be re-tested, and determinations made regarding requirements for regression testing to check that fixes didn't create problems elsewhere. If a problem-tracking system is in place, it should encapsulate these processes. A variety of commercial problem-tracking/management software tools are available (see the section for web resources with listings of such tools). The following are items to consider in the tracking process:

  • Complete information such that developers can understand the bug, get an idea of it's severity, and reproduce it if necessary.
  • Bug identifier (number, ID, etc.)
  • Current bug status (e.g., 'Released for Retest', 'New', etc.)
  • The application name or identifier and version
  • The function, module, feature, object, screen, etc. where the bug occurred
  • Environment specifics, system, platform, relevant hardware specifics
  • Test case name/number/identifier
  • One-line bug description
  • Full bug description
  • Description of steps needed to reproduce the bug if not covered by a test case or if the developer doesn't have easy access to the test case/test script/test tool
  • Names and/or descriptions of file/data/messages/etc. used in test
  • File excerpts/error messages/log file excerpts/screen shots/test tool logs that would be helpful in finding the cause of the problem
  • Severity estimate (a 5-level range such as 1-5 or 'critical'-to-'low' is common)
  • Was the bug reproducible?
  • Tester name
  • Test date
  • Bug reporting date
  • Name of developer/group/organization the problem is assigned to
  • Description of problem cause
  • Description of fix
  • Code section/file/module/class/method that was fixed
  • Date of fix
  • Application version that contains the fix
  • Tester responsible for retest
  • Retest date
  • Retest results
  • Regression testing requirements
  • Tester responsible for regression tests
  • Regression testing results
A reporting or tracking process should enable notification of appropriate personnel at various stages. For instance, testers need to know when retesting is needed, developers need to know when bugs are found and how to get the needed information, and reporting/summary capabilities are needed for managers.

What is 'configuration management'?
Configuration management covers the processes used to control, coordinate, and track: code, requirements, documentation, problems, change requests, designs, tools/compilers/libraries/patches, changes made to them, and who makes the changes. (See the section for web resources with listings of configuration management tools. Also see the section's 'Configuration Management' category for useful books with more information.)

What if the software is so buggy it can't really be tested at all?
The best bet in this situation is for the testers to go through the process of reporting whatever bugs or blocking-type problems initially show up, with the focus being on critical bugs. Since this type of problem can severely affect schedules, and indicates deeper problems in the software development process (such as insufficient unit testing or insufficient integration testing, poor design, improper build or release procedures, etc.) managers should be notified, and provided with some documentation as evidence of the problem.

How can it be known when to stop testing?
This can be difficult to determine. Most modern software applications are so complex, and run in such an interdependent environment, that complete testing can never be done. Common factors in deciding when to stop are:

  • Deadlines (release deadlines, testing deadlines, etc.)
  • Test cases completed with certain percentage passed
  • Test budget depleted
  • Coverage of code/functionality/requirements reaches a specified point
  • Bug rate falls below a certain level
  • Beta or alpha testing period ends

What if there isn't enough time for thorough testing?
Use risk analysis, along with discussion with project stakeholders, to determine where testing should be focused.
Since it's rarely possible to test every possible aspect of an application, every possible combination of events, every dependency, or everything that could go wrong, risk analysis is appropriate to most software development projects. This requires judgement skills, common sense, and experience. (If warranted, formal methods are also available.) Considerations can include:

  • Which functionality is most important to the project's intended purpose?
  • Which functionality is most visible to the user?
  • Which functionality has the largest safety impact?
  • Which functionality has the largest financial impact on users?
  • Which aspects of the application are most important to the customer?
  • Which aspects of the application can be tested early in the development cycle?
  • Which parts of the code are most complex, and thus most subject to errors?
  • Which parts of the application were developed in rush or panic mode?
  • Which aspects of similar/related previous projects caused problems?
  • Which aspects of similar/related previous projects had large maintenance expenses?
  • Which parts of the requirements and design are unclear or poorly thought out?
  • What do the developers think are the highest-risk aspects of the application?
  • What kinds of problems would cause the worst publicity?
  • What kinds of problems would cause the most customer service complaints?
  • What kinds of tests could easily cover multiple functionalities?
  • Which tests will have the best high-risk-coverage to time-required ratio?

What if the project isn't big enough to justify extensive testing?
Consider the impact of project errors, not the size of the project. However, if extensive testing is still not justified, risk analysis is again needed and the same considerations as described previously in apply. The tester might then do ad hoc testing, or write up a limited test plan based on the risk analysis.

How does a client/server environment affect testing?
Client/server applications can be quite complex due to the multiple dependencies among clients, data communications, hardware, and servers, especially in multi-tier systems. Thus testing requirements can be extensive. When time is limited (as it usually is) the focus should be on integration and system testing. Additionally, load/stress/performance testing may be useful in determining client/server application limitations and capabilities. There are commercial tools to assist with such testing. (See the section for web resources with listings that include these kinds of test tools.)

How can World Wide Web sites be tested?
Web sites are essentially client/server applications - with web servers and 'browser' clients. Consideration should be given to the interactions between html pages, web services, encrypted communications, Internet connections, firewalls, applications that run in web pages (such as javascript, flash, other plug-in applications), the wide variety of applications that could run on the server side, etc. Additionally, there are a wide variety of servers and browsers, various versions of each, small but sometimes significant differences between them, variations in connection speeds, rapidly changing technologies, and multiple standards and protocols. The end result is that testing for web sites can become a major ongoing effort. Other considerations might include:

  • What are the expected loads on the server (e.g., number of hits per unit time?), and what kind of performance is required under such loads (such as web server response time, database query response times). What kinds of tools will be needed for performance testing (such as web load testing tools, other tools already in house that can be adapted, load generation appliances, etc.)?
  • Who is the target audience? What kind and version of browsers will they be using, and how extensively should testing be for these variations? What kind of connection speeds will they by using? Are they intra- organization (thus with likely high connection speeds and similar browsers) or Internet-wide (thus with a wide variety of connection speeds and browser types)?
  • What kind of performance is expected on the client side (e.g., how fast should pages appear, how fast should flash, applets, etc. load and run)?
  • Will down time for server and content maintenance/upgrades be allowed? how much?
  • What kinds of security (firewalls, encryption, passwords, functionality, etc.) will be required and what is it expected to do? How can it be tested?
  • What internationilization/localization/language requirements are there, and how are they to be verified?
  • How reliable are the site's Internet connections required to be? And how does that affect backup system or redundant connection requirements and testing?
  • What processes will be required to manage updates to the web site's content, and what are the requirements for maintaining, tracking, and controlling page content, graphics, links, etc.?
  • Which HTML and related specification will be adhered to? How strictly? What variations will be allowed for targeted browsers?
  • Will there be any standards or requirements for page appearance and/or graphics throughout a site or parts of a site?
  • Will there be any development practices/standards utilized for web page components and identifiers, which can significantly impact test automation.
  • How will internal and external links be validated and updated? how often?
  • Can testing be done on the production system, or will a separate test system be required? How are browser caching, variations in browser option settings, connection variabilities, and real-world internet 'traffic congestion' problems to be accounted for in testing?
  • How extensive or customized are the server logging and reporting requirements; are they considered an integral part of the system and do they require testing?
  • How are flash, applets, javascripts, ActiveX components, etc. to be maintained, tracked, controlled, and tested?
Some sources of site security information include the Usenet newsgroup 'comp.security.announce' and links concerning web site security in the

Hundreds of web site test tools are available and more than 420 of them are listed in the .

How is testing affected by object-oriented designs?
Well-engineered object-oriented design can make it easier to trace from code to internal design to functional design to requirements. While there will be little affect on black box testing (where an understanding of the internal design of the application is unnecessary), white-box testing can be oriented to the application's objects. If the application was well-designed this can simplify test design.

What is Extreme Programming and what's it got to do with testing?
Extreme Programming (XP) is a software development approach for small teams on risk-prone projects with unstable requirements. It was created by Kent Beck who described the approach in his book 'Extreme Programming Explained' (See the ). Testing ('extreme testing') is a core aspect of Extreme Programming. Programmers are expected to write unit and functional test code first - before writing the application code. Test code is under source control along with the rest of the code. Customers are expected to be an integral part of the project team and to help develope scenarios for acceptance/black box testing. Acceptance tests are preferably automated, and are modified and rerun for each of the frequent development iterations. QA and test personnel are also required to be an integral part of the project team. Detailed requirements documentation is not used, and frequent re-scheduling, re-estimating, and re-prioritizing is expected. For more info on XP and other 'agile' software development approaches (Scrum, Crystal, etc.) see the resource listings in the section.