SOFTWARE TESTINGStatic Technique

Static Technique - Review

A way of testing software work products Program code, requirement spec., design spec. Test plan, test design, test cases, test script, user

guides Early defect detection and correction of software

development Development productivity improvements, reduce

development time, reduce testing cost and time Fewer defects and improved communication

Reviews, static analysis and dynamic testing have the same objective – identifying defects Reviews : find the cause of failures (defect) rather the defect

themselve Static analysis : complexity of code, error in statement, missing

parameter, Dead code etc.

Static Technique - Reviews

Static Technique

Manual Review Static Analysis

Formal Review

Informal Review

Inspection

Technical Review

Walkthrough

Informal Review

Why Review

More efficient detecting defects in review that in dynamic test Component test period; 2-4 findings per hour Code review; 6-10 findings per hour

Cost of fixing defects after component test level 10-14 m/h for finding and fixing defects

during integration or system test level 1 m/h for finding and fixing defect during

Inspection Time and cost efficiency when quick

defect correction

Reasons of review

Effective defects detecting Gaining understanding of

documentation Determining and deciding through

the discussion When auditing is planned Satisfying requirement or compliance Needed to be high quality in

developing process

Review – roles and responsibility

Manager Decide on the execution of reviews, allocates time in project

schedules and determine if the review objectives had been met Moderator

Leads the review of the document, planning the review and running the meeting and follow-up after meeting

Author The writer or person with chief responsibility of the

document(s) to be reviewed Reviewers

Checkers or inspectors Reviewers should be chosen to represent different perspectives

and roles in the review process

Scribe (recorder) Documents all the issues, problems and open points

Review Process

Step Role Goal

Planning Manager Assign role, define entry/exit criteria, identify documentation to be reviewd

Kick-off ModeratorReviewerAuthor

Distribute documentationExplain the goal of documentation and processCheck entry criteria for the review

Preparation

Reviewer Prepare about review meeting, try to find possible defects and comments

Review ModeratorReviewerAuthor/Scribe

Recording defects during the review meetingDo not try to solve the problem

Rework Author Fix the defect found (typically by author)

Follow Up Moderator Check all the defect found fixed, collect metrics and confirmCheck the exit criteria for the review.

Informal vs. formal review Informal Formal

Formal process

No Documented, defined defect detection process that includes peers and technical experts

Main purporse Inexpensive way to get some benefit

Discuss, make decision, evaluate alternatives, find defects, solve technical problems and check conformance to specifications and standards

Participants (optional) pair programming or a technical lead reviewing designs and code

Performed as a peer review without management participationModerator

Documentation

Optional Documented

Effect Vary in usefulness depending on reviewer

Consistent and quantity effect (when it succeed)

Preparation - Pre-meeting preparation

others - Ideally led by trained moderator(optional) the use of checklist, review report, list of findings and management participation

Types of review – Informal review

No formal process There may be pair programming or

technical lead reviewing designs and codes

Optionally may be documented May vary in usefulness depending on

the reviewer Main purpose – inexpensive way to

get some benefit

Types of review – Walkthrough

Meeting led by author Scenarios, dry runs, peer group Open-ended sessions Optionally a pre-meeting preparation of

reviewers, review report, list of findings and scribe

May vary in practice from quite formal to very formal

Main purporse : learning, gaining understanding, defect finding

Types of review – technical review

documented, defined defect-detection process that includes peers and technical experts;

may be performed as a peer review without management participation;

ideally led by trained moderator (not the author); pre-meeting preparation; optionally the use of checklists, review report, list of findings

and management participation; may vary in practice from quite informal to very formal; main purposes: discuss, make decisions, evaluate

alternatives, find defects, solve technical problems and check conformance to specifications and

standards

Types of review - Inspection led by trained moderator (not the author); usually peer examination; defined roles; includes metrics; formal process based on rules and checklists with entry

and exit criteria; pre-meeting preparation; inspection report, list of findings; formal follow-up process; optionally, process improvement and reader; main purpose: find defects.

Success factors for reviews

Each review has a clear predefined objective.

The right people for the review objectives are involved.

Defects found are welcomed, and expressed objectively.

People issues and psychological aspects are dealt with (e.g. making it a positive experience for the author).

Review techniques are applied that are suitable to the type and level of software work products and reviewers.

Checklists or roles are used if appropriate to increase effectiveness of defect identification.

Training is given in review techniques, especially the more formal techniques, such as inspection.

Management supports a good review process (e.g. by incorporating adequate time for review activities in project schedules).

There is an emphasis on learning and process improvement.