Software Inspection vs Software Testing: How do they differ?

Software inspection and software testing refer to two different stages in a broader software quality assurance strategy. Through this post, let’s explore the difference between these two terms.

Software Inspection vs Software Testing – Overview

What is Software Inspection?

Software inspection refers to a peer review of software to identify bugs or defects at the early stages of SDLC. It is a formal review that ensures the documentation produced during a given stage is consistent with previous stages and conforms to preestablished rules and standards.

Software inspection involves people examining the software product to discover defects and inconsistencies. Since it doesn’t require system execution, inspection is usually done before implementation.

What is Software Testing?

Software testing refers to verifying and evaluating that software does what it is expected to do. It is done to discover bugs, errors or defects before the software is used.

When you test a software product or application, you execute a program using artificial data and verify the results of the test run for errors, variations, or information about the program’s non-functional attributes.

Software Testing enables teams to identify and resolve potential problems before they affect actual users. The QA professionals must test the software with a proper Software Testing strategy to ensure the software’s performance, efficiency, and reliability.

Software Testing is part of a more general verification and validation process. It reveals the presence of errors, not their absence.

Software Inspection vs Software Testing – Detailed Comparison

What is the purpose of software inspection?

Software inspection aims to identify software defects and deviations, ensuring the product meets customer requirements, wants, and needs. In a broader context, the objective of the inspection is to inhibit defective software from flowing down the subsequent operations, thereby preventing loss to the company.

Software inspection is designed to unravel defects or bugs, unlike testing, which is done to make corrections. It is divided into two types:

• Document inspection: Here, the documents produced for a given phase are inspected, further focusing on their quality, correctness, and relevance.
• Code inspection: The code, program source files, and test scenarios are inspected and reviewed.

Who are the key parties involved in Software Inspection?

• Moderator: A facilitator who organizes and reports on inspection.
• Author: A person who produces the report.
• Reader: A person who guides the examination of software; more of a paraphraser.
• Recorder: An inspector who logs all the defects on the defect list.
• Inspector: The inspection team member responsible for identifying the defects.

What is the software inspection process?

Software inspection involves six steps – Planning, Overview, Preparation, Meeting, Rework, and Follow-up.

Planning

The planning phase starts with the selection of a group review team. A moderator plans the activities performed during the inspection and verifies that the software entry criteria are met.

Overview

The overview phase intends to disseminate information regarding the background of the product under review. Here, a presentation is given to the inspector with some background information needed to review the software product properly.

Preparation

In the individual preparation phase, the inspector collects all the materials needed for inspection. Each reviewer studies the project individually and notes the issues they encounter.

Meeting

The moderator conducts the meeting to collect and review defects. Here, the reader reads through the product line by line while the inspector points out the flaws. All issues are raised, and suggestions may be recorded.

Rework

Based on meeting notes, the author changes the work product.

Follow-up

In the last phase, the moderator verifies if necessary changes are made to the software product, compiling a defect summary report.

What is the purpose of software testing?

The purpose of software testing is to identify errors, disparities, or missing requirements contrary to actual requirements.

Software testing identifies bugs and defects in the development process so they’re repaired before the launch. This is done to ensure that only quality products reach consumers, ensuring customer satisfaction.

What is the software testing process?

Software testing is a process rather than a single activity. Let’s look at the components that make up the whole.

Requirements Analysis

The first step requires the QA team to comprehend the software requirements. They meet different organizations, stakeholders, teams, etc. Once the requirements are understood, the next step is identifying the components or parts of software that ought to be tested.

Test Planning

This stage involves the team planning the strategy and approach. Typically, the test manager carries out this activity to look after certain factors such as how much effort testing requires how much testing costs, and which types of testing to do.

Test Case Designing

The team develops the test case based on specific criteria and scope. Once the test planning is done, the development of test cases begins. Here, the testing team designs the test cases for execution, which are then delivered to the QA team for an examination.

Test Environment Setup

This means setting up all software and hardware resources for the testing team to execute all the test cases. Simply put, this stage decides the conditions on which the software is tested.

Test Execution

The testing team now executes tests based on test planning and marks the test report. If the test case is successfully completed, it is marked as passed. If the test case is failed, it is marked as failed, and the corresponding defect or error is reported to the development team. If the test case is blocked due to a mistake, it is marked as blocked.

Test Closure

This phase ensures the completion of test execution. Several activities are undertaken, such as test completion reporting, collection of test completion matrices, and test results. Once this cycle is completed, the test cycle closure report is prepared.

SDLC without Inspection

Imagine a software development life cycle without inspection. What possibly could go wrong? Aren’t we testing our software to detect defects?

Usually, we assume that defects or bugs are related to code only, which can be identified by testing! Does that mean there are no other defects? Well, that’s not true.

Defects can occur before coding even starts. Such defects can originate in all stages due to inaccurate specifications, insufficient requirements, or incorrect feature implementation.

As shown above, defects in the previous stages of SDLC get identified in the maintenance stage, which adds stress to the maintenance stage.

This increases costs and time to repair or resolve defects, leading to late delivery, low production, and longer release cycles.

SDLC with Inspection

Imagine where defects found in each stage get removed or fixed before moving on to the next phase. Great, isn’t it? That’s what inspection helps you with.

When inspections are incorporated and applied, they save us from chaos zone and minimize the cost of solving defects. This leads to increased production and shorter release cycles, ensuring software quality.

Key Differences between Software Inspection and Software Testing

Software inspection involves examining a product to ensure it complies with the end user’s requirements and specifications. In contrast, software testing tests the product to ensure it does what it is supposed to do and is ready to be used by consumers.

To understand the underlying difference between the two, we have listed the types of errors identified by both processes:

Types of Bugs/Errors	Software Inspection	Software Testing
Checks the complexity of Code	Yes	No
Reviews Code Structure	Yes	No
Identifies interface defects at module level	Yes	No
Checks if new features are to be added	Yes	No
Identifies and resolves boundary level defects	Yes	Yes
Resolve performance errors	Yes	Yes
Checks if any features are implemented incorrectly	Yes	Yes

Conclusion

In software engineering, quality is the primary focus of any project. As evident, software testing and inspection are two different steps that are carried out when ensuring the overall quality of a product.

However, these processes are not mutually exclusive. Instead, they complement each other, so you shouldn’t ignore one in favor of the other.

Frequently Asked Questions

What are the similarities between software testing and inspection?

Both testing and inspection are integral in ensuring that not only is your software of the highest quality, but it also meets customer requirements. Simply put, both processes help detect and prevent quality issues and defects before the product is released to the consumer market.

Why is software inspection more important than testing?

Software inspection is more involved than testing as it covers a broader context regarding ensuring software quality.

Software testing is the process of evaluating the product and whether it works appropriately per specifications/requirements. Software inspection is testing plus code review to ensure that it is correct, optimized, and maintainable. Simply put, the goal of the inspection is to remove errors and reduce the cost of rework.