Testing is the process of executing a program to find errors. To make our software perform well it should be error-free. If testing is done successfully it will remove all the errors from the software. In this article, we will discuss first the principles of testing and then we will discuss, the different types of testing.
Principles of Testing
- All the tests should meet the customer’s requirements.
- To make our software testing should be performed by a third party.
- Exhaustive testing is not possible. As we need the optimal amount of testing based on the risk assessment of the application.
- All the tests to be conducted should be planned before implementing it
- It follows the Pareto rule(80/20 rule) which states that 80% of errors come from 20% of program components.
- Start testing with small parts and extend it to large parts.
- Types of Testing
There are basically 10 types of Testing.
- Unit Testing
- Integration Testing
- System Testing
- Functional Testing
- Acceptance Testing
- Smoke Testing
- Regression Testing
- Performance Testing
- Security Testing
- User Acceptance Testing
Types of Software Testing
Unit Testing
Unit testing is a method of testing individual units or components of a software application. It is typically done by developers and is used to ensure that the individual units of the software are working as intended. Unit tests are usually automated and are designed to test specific parts of the code, such as a particular function or method. Unit testing is done at the lowest level of the software development process, where individual units of code are tested in isolation.
Advantages of Unit Testing: Some of the advantages of Unit Testing are listed below.
- It helps to identify bugs early in the development process before they become more difficult and expensive to fix.
- It helps to ensure that changes to the code do not introduce new bugs.
- It makes the code more modular and easier to understand and maintain.
- It helps to improve the overall quality and reliability of the software.
Note: Some popular frameworks and tools that are used for unit testing include JUnit, NUnit, and xUnit.
It’s important to keep in mind that Unit Testing is only one aspect of software testing and it should be used in combination with other types of testing such as integration testing, functional testing, and acceptance testing to ensure that the software meets the needs of its users.
It focuses on the smallest unit of software design. In this, we test an individual unit or group of interrelated units. It is often done by the programmer by using sample input and observing its corresponding outputs.
Example:
a) In a program we are checking if the loop, method, or function is working fine.
b) Misunderstood or incorrect, arithmetic precedence.
c) Incorrect initialization.
Integration Testing
Integration testing is a method of testing how different units or components of a software application interact with each other. It is used to identify and resolve any issues that may arise when different units of the software are combined. Integration testing is typically done after unit testing and before functional testing and is used to verify that the different units of the software work together as intended.
Different Ways of Performing Integration Testing: There are different ways of Integration Testing that are discussed below.
- Top-down integration testing: It starts with the highest-level modules and differentiates them from lower-level modules.
- Bottom-up integration testing: It starts with the lowest-level modules and integrates them with higher-level modules.
- Big-Bang integration testing: It combines all the modules and integrates them all at once.
- Incremental integration testing: It integrates the modules in small groups, testing each group as it is added.
Advantages of Integrating Testing
- It helps to identify and resolve issues that may arise when different units of the software are combined.
- It helps to ensure that the different units of the software work together as intended.
- It helps to improve the overall reliability and stability of the software.
- It’s important to keep in mind that Integration testing is essential for complex systems where different components are integrated together.
- As with unit testing, integration testing is only one aspect of software testing and it should be used in combination with other types of testing such as unit testing, functional testing, and acceptance testing to ensure that the software meets the needs of its users.
The objective is to take unit-tested components and build a program structure that has been dictated by design. Integration testing is testing in which a group of components is combined to produce output.
Integration testing is of four types: (i) Top-down (ii) Bottom-up (iii) Sandwich (iv) Big-Bang
Example:
(a) Black Box testing:- It is used for validation. In this, we ignore internal working mechanisms and focus on what is the output?.
(b) White box testing:- It is used for verification. In this, we focus on internal mechanisms i.e. how the output is achieved?.
Regression Testing
Regression testing is a method of testing that is used to ensure that changes made to the software do not introduce new bugs or cause existing functionality to break. It is typically done after changes have been made to the code, such as bug fixes or new features, and is used to verify that the software still works as intended.
Regression testing can be performed in different ways, such as:
- Retesting: This involves testing the entire application or specific functionality that was affected by the changes.
- Re–execution: This involves running a previously executed test suite to ensure that the changes did not break any existing functionality.
- Comparison: This involves comparing the current version of the software with a previous version to ensure that the changes did not break any existing functionality.
Advantages of Regression Testing
- It helps to ensure that changes made to the software do not introduce new bugs or cause existing functionality to break.
- It helps to ensure that the software continues to work as intended after changes have been made.
- It helps to improve the overall reliability and stability of the software.
- It’s important to keep in mind that regression testing is an ongoing process that should be done throughout the software development
- lifecycle to ensure that the software continues to work as intended. It should be automated as much as possible to save time and resources. Additionally, it’s important to have a well-defined regression test suite that covers
Every time a new module is added leads to changes in the program. This type of testing makes sure that the whole component works properly even after adding components to the complete program.
Example
In school records, suppose we have module staff, students, and finance combining these modules
and checking if the integration of these modules works fine in regression testing.
Smoke Testing
Smoke Testing is done to make sure that the software under testing is ready or stable for further testing
It is called a smoke test as the testing of an initial pass is done to check if it did not catch fire or smoke in the initial switch-on.
Example:
If the project has 2 modules so before going to the module make sure that module 1 works properly.
Alpha Testing
Alpha testing is a type of validation testing. It is a type of acceptance testing that is done before the product is released to customers. It is typically done by QA people.
Example:
When software testing is performed internally within the organisation.
Beta Testing
The beta test is conducted at one or more customer sites by the end-user of the software. This version is released for a limited number of users for testing in a real-time environment.
Example:
When software testing is performed for the limited number of people.
System Testing
System Testing is carried out on the whole system in the context of either system requirement specifications or functional requirement specifications or in the context of both. The software is tested such that it works fine for the different operating systems. It is covered under the black box testing technique. In this, we just focus on the required input and output without focusing on internal work. In this, we have security testing, recovery testing, stress testing, and performance testing.
Example:
This includes functional as well as nonfunctional testing.
Stress Testing
In Stress Testing, we give unfavorable conditions to the system and check how they perform in those conditions.
Example:
i. Test cases that require maximum memory or other resources are executed.
ii. Test cases that may cause thrashing in a virtual operating system.
ii. Test cases that may cause excessive disk requirement Performance Testing.
It is designed to test the run-time performance of software within the context of an integrated system. It is used to test the speed and effectiveness of the program. It is also called load testing. In it, we check, what is the performance of the system in the given load.
Example:
Checking several processor cycles.
Object-Oriented Testing
Object-Oriented Testing testing is a combination of various testing techniques that help to verify and validate object-oriented software. This testing is done in the following manner:
- Testing of Requirements,
- Design and Analysis of Testing,
- Testing of Code,
- Integration testing,
- System testing,
- User Testing.
Acceptance Testing
Acceptance testing is done by the customers to check whether the delivered products perform the desired tasks or not, as stated in the requirements. We use Object-Oriented Testing for discussing test plans and for executing the projects.
Advantages of Software Testing
- Improved software quality and reliability.
- Early identification and fixing of defects.
- Improved customer satisfaction.
- Increased stakeholder confidence.
- Reduced maintenance costs.
Disadvantages of Software Testing
- Time-Consuming and adds to the project cost.
- This can slow down the development process.
- Not all defects can be found.
- Can be difficult to fully test complex systems.
- Potential for human error during the testing process.
Questions For Practice
1. With respect to Software Testing, consider a flow graph G with one connected component. Let E be the number of edges, N be the number of nodes, and P be the number of predicate nodes of G. Consider the following four expressions: [GATE IT -2006]
I. E-N+P
II. E-N+2
III. P+2
IV. P+1
The cyclomatic complexity of G is given by
(A) I or III
(B) II or III
(C) II or IV
(D) I or IV
Solution: Correct Answer is (C).
Frequently Asked Questions
1. What is a Test Case?
Answer:
Test Cases can be simply determined as conditions that a tester will check whether the code runs perfectly or not.
2. What is the use of automation testing?
Answer:
Automation Testing is used to reduce the testing efforts, also testing faster delivering capability.
