The Art of Test Case Authoring - Part 2

In Part 1 we have seen how ot author test cases using Functional Specifications. Now let us see Authoring Test Cases Using Use Cases.

Authoring Test Cases Using Use Cases

A use case is a sequence of actions performed by a system, which combined together produce, a result of value to a system user. While use cases are often associated with object-oriented systems, they apply equally well to most other types of systems.

Use cases and test cases work well together in two ways: If the use cases for a system are complete, accurate, and clear, the process of deriving the test cases is straightforward. And if the use cases are not in good shape, the attempt to derive test cases will help to debug the use cases.

Advantages of Test Cases derived from Use Cases

Traditional test case design techniques include analyzing the functional specifications, the software paths, and the boundary values. These techniques are all valid, but use case testing offers a new perspective and identifies test cases which the other techniques have difficulty seeing.

Use cases describe the “process flows” through a system based on its actual likely use, so the test cases derived from use cases are most useful in uncovering defects in the process flows during real-world use of the system (that moment you realize “we can’t get there from here!”). They also help uncover integration bugs, caused by the interaction and interference of different features, which individual feature testing would not see. The use case method supplements (but does not supplant) the traditional test case design techniques.

What one should know before converting the Use cases into test cases?

 Business logic and terminologies of the vertical.
 Technical complexities and environment compatibilities of the application.
 Limitations of the application and its design.
 Software testing experience.

How to approach in deriving test cases from Use cases?

 Read and understand the objective of the use case.
 Identify the conditions involved in the use case.
 Identify the relations between the conditions within a use case.
 Identify the dependencies of a use case with another.
 Check the functional flow.
 If you suspect an issue in any manner, get it resolved from your client or designing team.
 Break down the positive and negative test scenarios from each condition.
 Collect test data for the identified scenarios.
 Prepare a high-level test case index with unique test id.
 If you have the prototype of the application, compare the test scenarios with the prototype and review the test case index.
 Convert the test scenarios into test cases.

The first step is to develop the Use Case topics from the functional requirements of the Software Requirement Specification. The Use Case topics are depicted as an oval with the Use Case name.

The Use Case diagram just provides a quick overview of the relationship of actors to Use Cases. The meat of the Use Case is the text description. This text will contain the following:

Name
Brief Description
SRS Requirements Supported
Pre & Post Conditions
Event Flow

In the first iteration of Use Case definition, the topic, a brief description and actors for each case are identified and consolidated. In the second iteration the Event Flow of each Use Case can be flushed out. The Event Flow may be the personification and role-playing of the requirements specification. The requirements in the Software Requirement Specification are each uniquely numbered so that they may be accounted for in the verification testing. These requirements should be mapped to the Use Case that satisfies them for accountability.

The Pre-Condition specifies the required state of the system prior to the start of the Use Case. This can be used for a similar purpose in the Test Case. The Post-Condition is the state of the system after the actor interaction. This may be used for test pass/fail criteria.

The event flow is a description (usually a list) of the steps of the actor’s interaction with the system and the system’s required response. Recall that system is viewed as a black box. The event flow contains exceptions, which may cause alternate paths through the event flow. The following is an example of a Use Case for telephone systems.

Test case Management and Test Case authoring tools

Once the Test cases are developed they need to be maintained in the proper way to avoid confusion as which test cases are executed and which are not and which have been passed or failed. That is the status of the test cases needs to be maintained.
So, the most important activity to protect the value of test cases is to maintain them so that they are testable. They should be maintained after each testing cycle, since testers will find defects in the cases as well as in the software.

Test cases lost or corrupted by poor versioning and storage defeat the whole purpose of making them reusable. Configuration management (CM) of cases should be handled by the organization or project, rather than the test management. If the organization does not have this level of process maturity, the test manager or test writer needs to supply it. Either the project or the test manager should protect valuable test case assets with the following configuration management standards:

 Naming and numbering conventions
 Formats, file types
 Versioning
 Test objects needed by the case, such as databases
 Read only storage
 Controlled access
 Off-site backup

Test Case Authoring Tools

Improving productivity with test management software:

Software designed to support test authoring is the single greatest productivity booster for writing test cases. It has these advantages over word processing, database, or spreadsheet software:

 Makes writing and outlining easier
 Facilitates cloning of cases and steps
 Easy to add, move, delete cases and steps
 Automatically numbers and renumbers
 Prints tests in easy-to-follow templates

Test authoring is usually included in off-the-shelf test management software, or it could be custom written. Test management software usually contains more features than just test authoring. When you factor them into the purchase, they offer a lot of power for the price. If you are shopping for test management software, it should have all the usability advantages listed just above, plus additional functions:

 Exports tests to common formats
 Multi-user
 Tracks test writing progress, testing progress
 Tracks test results, or ports to database or defect tracker
 Links to requirements and/or creates coverage matrixes
 Builds test sets from cases
 Allows flexible security

There are many test case authoring tools available in the market today. Here we will limit the discussion to Mercury’s Test Director and the in-house tool TestLinks.

Mercury Interactive’s Test Director

By far the most familiar tool for maintaining Test Cases is Mercury Interactive’s Test Director. Test Director helps organizations deploy high-quality applications more quickly and effectively. It has four modules—Requirements Manager, Test Plan, Test Lab and Defects Manager. These allow for a smooth information flow between various testing stages. The completely web-enabled Test Director supports high levels of communication and collaboration among distributed testing teams.

Features & benefits of Test Director

Supports the Entire Testing Process Test Director incorporates all aspects of the testing process— requirements management, planning, scheduling, running tests, issue management and project status analysis—into a single browser-based application.

Provides Anytime, Anywhere Access to Testing Assets

Using Test Director’s Web interface, testers, developers and business analysts can participate in and contribute to the testing process by collaborating across geographic and organizational boundaries.

Provides Traceability Throughout the Testing Process

Test Director links requirements to test cases, and test cases to issues, to ensure traceability throughout the testing cycle. When requirement changes or the defect is fixed, the tester is notified of the change.

Integrates with Third-Party Applications

Whether you're using an industry standard configuration management solution, Microsoft Office, or a homegrown defect management tool, any application can be integrated into Test Director. Through its open API, Test Director preserves your investment in existing solutions and enables you to create an end-to-end lifecycle-management solution.

Manages Manual and Automated Tests

Test Director stores and runs both manual and automated tests, and can help jumpstart your automation project by converting manual tests to automated test scripts.

Accelerates Testing Cycles

Test Director’s Test Lab Manager accelerates the test execution cycles by scheduling and running tests automatically—unattended, even overnight. The results are reported into Test Director’s central repository, creating an accurate audit trail for analysis.

Facilitates Consistent and Repetitive Testing Process

By providing a central repository for all testing assets, Test Director facilitates the adoption of a more consistent testing process, which can be repeated throughout the application lifecycle or shared across multiple applications or lines of business (LOBs).

Provides Analysis and Decision Support Tools

Test Director’s integrated graphs and reports help analyze application readiness at any point in the testing process. Using information about requirements coverage, planning progress, run schedules or defect statistics, QA managers are able to make informed decisions on whether the application is ready to go live.