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Are functional testing and integration testing the same?
You begin your testing through unit testing, then after completing unit testing you go for integration testing where you test the system as a whole. Is functional testing the same as integration testing? You still taking the system as a whole and testing it for functionality conformance.
Integration testing is when you test more than one component and how they function together. For instance, how another system interacts with your system, or the database interacts with your data abstraction layer. Usually, this requires a fully installed system, although in its purest forms it does not.
Functional testing is when you test the system against the functional requirements of the product. Product/Project management usually writes these up and QA formalizes the process of what a user should see and experience, and what the end result of those processes should be. Depending on the product, this can be automated or not.
Functional Testing:
Yes, we are testing the product or software as a whole functionally whether it is functionally working properly or not (testing buttons, links etc.)
For example: Login page.
you provide the username and password, you test whether it is taking you to home page or not.
Integration Testing:
Yes, you test the integrated software only but you test where the data flow is happening and is there any changes happening in the database.
For example: Sending e-mail
You send one mail to someone, there is a data flow and also change in database (the sent table increases value by 1)
Remember - clicking links and images is not integration testing. Hope you understood why, because there is no change in database by just clicking on a link.
Hope this helped you.
Functional Testing: It is a process of testing where each and every component of the module is tested. Eg: If a web page contains text field, radio botton, Buttons and Drop down etc components needed to be checked.
Integration Testing: Process where the dataflow between 2 modules are checked.
This is an important distinction, but unfortunately you will never find agreement. The problem is that most developers define these from their own point of view. It's very similar to the debate over Pluto. (If it were closer to the Sun, would it be a planet?)
Unit testing is easy to define. It tests the CUT (Code Under Test) and nothing else. (Well, as little else as possible.) That means mocks, fakes, and fixtures.
At the other end of the spectrum there is what many people call system integration testing. That's testing as much as possible, but still looking for bugs in your own CUT.
But what about the vast expanse between?
For example, what if you test just a little bit more than the CUT? What if you include a Fibonacci function, instead of using a fixture which you had injected? I would call that functional testing, but the world disagrees with me.
What if you include time() or rand()? Or what if you call http://google.com? I would call that system testing, but again, I am alone.
Why does this matter? Because system-tests are unreliable. They are necessary, but they will sometimes fail for reasons beyond your control. On the other hand, functional tests should always pass, not fail randomly; if they are fast, they might as well be used from the start in order to use Test-Driven Development without writing too many tests for your internal implementation. In other words, I think that unit-tests can be more trouble than they are worth, and I have good company.
I put tests on 3 axes, with all their zeroes at unit-testing:
Functional-testing: using real code deeper and deeper down your call-stack.
Integration-testing: higher and higher up your call-stack; in other words, testing your CUT by running the code which would use it.
System-testing: more and more unrepeatable operations (O/S scheduler, clock, network, etc.)
A test can easily be all 3, to varying degrees.
I would say that both are tightly linked to each other and very tough to distinguish between them.
In my view, Integration testing is a subset of functional testing.
Functionality testing is based on the initial requirements you receive. You will test the application behaviour is as expected with the requirements.
When it comes to integration testing, it is the interaction between modules. If A module sends an input, B module able to process it or not.
Integration testing - Integration testing is nothing but the testing of different modules. You have to test relationship between modules. For ex you open facebook then you see login page after entering login id and password you can see home page of facebook hence login page is one module and home page is another module. you have to check only relationship between them means when you logged in then only home page must be open not message box or anything else. There are 2 main types of integration testing TOP-DOWN approach and BOTTOM UP approach.
Functional Testing - In functional testing you have to only think about input and output. In this case you have to think like a actual user. Testing of What input you gave and what output you got is Functional testing. you have to only observe output. In functional testing you don't need to test coding of application or software.
In a Functional testing tester focuses only Functionality and sub functionality of application. Functionality of app should be working properly or not.
In integration testing tester have to check dependency between modules or sub-modules.Example for modules records should be fetching and displayed correctly in another module.
Integration Test:-
When Unit testing is done and issues are resolved to the related components then all the required components need to integrate under the one system so that it can perform an operation.
After combining the components of the system,To test that whether the system is working properly or not,this kind of testing is called as Integration Testing.
Functional Testing:-
The Testing is mainly divided into two categories as
1.Functional Testing
2.Non-Functional Testing
**Functional Testing:-
To test that whether the software is working according to the requirements of the user or not.
**Non-Functional Testing:-
To test that whether the software satisfies the quality criteria like Stress Test,Security test etc.
Usually,Customer will provide the requirements for Functional Test only and for Non Functional test,Requirements should not be mentioned but the application necessarily perform those activity.
Integration testing It can be seen as how the different modules of the system work together.
We mostly refers to the integrated functionality of the different modules, rather different components of the system.
For any system or software product to work efficiently, every component has to be in sync with each other.
Most of the time tool we used for integration testing will be chosen that we used for unit testing.
It is used in complex situations, when unit testing proves to be insufficient to test the system.
Functional Testing
It can be defined as testing the individual functionality of modules.
It refers to testing the software product at an individual level, to check its functionality.
Test cases are developed to check the software for expected and unexpected results.
This type of testing is carried out more from a user perspective. That is to say, it considers the expectation of the user for a type of input.
It is also referred as black-box testing as well as close-box testing
Checking the functionality of the application is generally known as functional testing, where as the integration testing is to check the flow of data from one module to other.
Lets take example of money transfer app.Suppose we have page in which we enter all the credentials and if we press transfer button and after that if we getting any success, Then this is functional testing. But in same example if we verify the amount transfer then it is integration testing.
Authors diverge a lot on this. I don't believe there is "the" correct interpretation for this. It really depends.
For example: most Rails developers consider unit tests as model tests, functional tests as controller tests and integration tests as those using something like Capybara to explore the application from a final user's perspective - that is, navigating through the page's generated HTML, using the DOM to check for expectations.
There is also acceptance tests, which in turn are a "live" documentation of the system (usually they use Gherkin to make it possible to write those in natural language), describing all of the application's features through multiple scenarios, which are in turn automated by a developer. Those, IMHO, could be also considered as both, functional tests and integration tests.
Once you understand the key concept behind each of those, you get to be more flexible regarding the right or wrong. So, again IMHO, a functional test could also be considered an integration test. For the integration test, depending on the kind of integration it's exercising, it may not be considerate a functional test - but you generally have some requirements in mind when you are writing an integration test, so most of the time it can be also considerate as a functional test.
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In the context of Agile software development, what's the difference between User Acceptance Test (UAT), Test Case Scenario and Functional Test?
The members of the team I am part of, they consider the three things as different, but I see them as exactly the same thing.
In fact, all of them are designed having the end user in mind
There's a lot of different sorts of testing. Many of them overlap. Many use the same tools. Many are specializations of other more general terms. Often they blur together. People argue about the terminology all the time.
You're correct that they all have the end user in mind, but they are different.
User Acceptance Test
This is a specific form of an acceptance test where a subject-matter expert, ideally the client or their representative, tests the software. This is in addition to functional and acceptance testing done by QA. It's designed to simulate, as closely as possible, an actual end-user using the software; the tester is asked to perform a bunch of common tasks with the new system, but not given specific instructions nor coaching on how to do it.
For example, if you were creating a site for an airline, they might be asked to register, login, book a flight, make a payment, check in, check their flight status, and so on.
Functional Test
This is blackbox testing done by the QA role. It verifies the thing does what it's supposed to do; you give it inputs, you check the outputs. Typically this is testing against the specification and/or requirements document.
"Functional" here doesn't refer to code functions, but that the system functions as expected. Testing specific functions is unit testing.
They can be purely functional, "when I do X I get Y". They can be about resource use, "when I do X it uses no more than Y memory/time". Or about error checking, "when I give it garbage I get a well formed error". Anything that validates it meets the requirements.
Test Case Scenario
Sounds like Scenario Testing: this uses stories, similar to user stories, that help a tester work through a complicated testing scenario. Scenario testing tests complicated combinations of things which might arise during actual use and often cut across multiple systems.
An example of a test scenario might be: "in the middle of processing the system runs out of disk space; verify an admin is notified, that processing resumes once space is cleared, and that no data is lost".
A User Acceptance Test might use Scenario Testing.
These are my rules of thumb:
Unit testing: does this one function work?
Integration testing: do the functions work together?
Functional testing: does it function as required?
Acceptance testing: is it acceptable to the client?
Regression testing: does it still work like it used to?
User Acceptance Testing is having business users trying out your app.
There is also an Acceptance Testing done by QA when they check the new functionality - you can call it a Story Acceptance Testing to distinguish between these. These are not necessarily Functional Tests (could be Security, Performance testing, etc.).
Test Case is a number of steps to check a small piece of functionality. It has Prerequisites, Steps, Expected Result, Actual Result. This is one of the ways of carrying out Functional Testing. Others could be: exploratory testing, checklists.
Test Scenario - steps that cover a bigger picture. Often they cover cases of how real users would use the app. But these are carried out by QA team.
Functional Test - a test that checks the functionality as opposed to e.g. Performance. This can be a unit test as well, but since this terminology is mostly used by QA - when people talk about them they usually mean Functional System Test.
Note, that different authorities may use different definitions of the same terms. Check out Holes in testing terminology: Test Types and Test Levels. Since it's impossible to find the one true terminology it's more important that you use terms consistently within your team even if they are used differently in other companies and teams.
User acceptance testing is a process that obtains confirmation that a system meets agreed customer/product manager requirements.
Functional Testing is actual functionality test of the software there can be many different types of testing but in simple word testing the functionality what is should be expected.
The test scenario is the high level of testing cases when the first classification of module testing then module dividing into a scenario and at last small and specifical test steps with expected result says test cases, so the test scenario is group test cases with limited to specific functionality and module.
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I heard that system testing has two types
1)functional Testing
2)Non functional testing
But later in another website i have seen below statements
In the types of functional testing following testing types should be cover:
Unit Testing
Smoke testing
Sanity testing
Integration Testing
Interface Testing
System Testing
Regression Testing
UAT
I am confused, Please clarify me that whether the system testing includes functional or functional testing includes system testing and the sequence of these testings(functional is performed first or system)
Thanks
Functional testing aims to figure out whether given functionality works as specified. System testing aims to figure out whether the whole system fulfills the requirements given to it.
So in functional testing you test that given part of the whole system functions in a specified way. And in system testing you test the system as a whole fulfills the requirements given to it.
For example testing that 1+1=2 tests the plus function and sum function. And thus is a functional test. Testing whether user can calculate correct amount of tip using the calculator or not, is a system test, since it tests a requirement (calculate tip), but not a specific function of the application.
And non-functional testing includes stuff like usability and performance.
Functional testing are based on an analysis of requirements specification of a component or system.
Non-functional testing includes, but is not limited to, performance testing, load testing, stress testing, usability testing, maintainability,reliability, portability. It is the testing o how the system works.
You can call System Testing as a level of Test, instead Functional Testing is a Test Type. And System testing should investigate functional a non-functional areas of the system.
You could find more information on this subject if you read for example "ISQTB - Foundation Level Syllabus".
Non-functional testing would include, for example, performance testing - something unrelated to the actual business requirement.
Functional testing tests the business requirements.
Sometimes there is an overlap between the two.
System Testing includes both Function testing as well as non Function Testing
Functional and non functional testing is done for a particular portion or is done step by step which becomes System testing.
Functional Testing : are based on an Requirement Specification. while you check application as per flow and if u find any bug for that flow then it will functional testing.
System Testing : are test whole application.
Unit Testing : One individual parts of an application, called units, are individually and independently scrutinized for proper operation.
Regression testing : while Dev team change any module and then module not effect another module that is Regression testing.
System testing is a combination of both functional and non-functional testing.
Functional testing, in simple terms, tests the functionality of whether an application is working to requirements or not. (smoke, sanity, retesting, regression, priority based testing, riskbased testing etc.)
Non-functional tests evaluate the non functional parts such as performance, load, stress, volume, usability(userfriendliness), look and feel etc.
Functinal testing comes under System testing (which checks the overall end to end flow of an application).
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We are building a large CRM system based on the SalesForce.com cloud. I am trying to put together a test plan for the system but I am unsure how to create system-wide tests. I want to use some behaviour-driven testing techniques for this, but I am not sure how I should apply them to the platform.
For the custom parts we will build in the system I plan to approach this with either Cucumber of SpecFlow driving Selenium actions on the UI. But for the SalesForce UI Customisations, I am not sure how deep to go in testing. Customisations such as Workflows and Validation Rules can encapsulate a lot of complex logic that I feel should be tested.
Writing Selenium tests for this out-of-box functionality in SalesForce seems overly burdensome for the value. Can you share your experiences on System testing with the SalesForce.com platform and how should we approach this?
That is the problem with detailed test plan up front. You trying to guess what kind of errors, how many, and in what areas you will get. This may be tricky.
Maybe you should have overall Master Test Plan specifying only test strategy, main tool set, risks, relative amount of how much testing you want to put in given areas (based on risk).
Then when you starting to work on given functionality or iteration (I hope you are doing this in iterations not waterfall), you prepare detailed test plan for this set of work. You adjust your tools/estimates/test coverage based on experiences from previous parts.
This way you can say at the beginning what is your general approach and priorities, but you let yourself adapt later as project progresses.
Question about how much testing you need to put into testing COTS is the same as with any software: you need to evaluate the risk.
If your software need to be
Validated because of external
regulations (FDA,DoD..)
you will need to go deep with your
tests, almost test entire app. One
problem here may be ensuring
external regulator, that tools you
used for validation are validated
(and that is a troublesome).
If your application is
mission-critical for your company,
than you still need to do a lot of
testing based on extensive risk
analysis.
If your application is not concerned
with all above, you can go with
lighter testing. Probably you can
skip functionality that was tested
by platform manufacturer, and focus
on your customisations. On the other
hand I would still write tests (at
least happy paths) for
workflows you will be using in your
business processes.
When we started learning Selenium testing in 2008 we created Recruiting application from SalesForce handbook and created a suite of tests and described our path step by step in our blog. It may help you get started if you decide to write Selenium code to test your app.
I believe the problem with SalesForce is you have Unit and UI testing, but no Service-level testing. The SpecFlow I've seen which drives Selenium UI is brittle and doesn't encapsulate what I'm after in engineering a service-level test solution:
( When I navigate to "/Selenium-Testing-Cookbook-Gundecha-Unmesh/dp/1849515743"
And I click the 'buy now' button
And then I click the 'proceed to checkout' button)
That is not the spirit or intent of Specflow.
Given I have not selected a product
When I select Proceed to Checkout
Then ensure I am presented with a message
In order to test that with selenium, you essentially have to translate that to clicks and typing, whereas in the .NET realm, you can instantiate objects, etc., in the middle-tier, and perform hundreds of instances and derivations against the same BACKGROUND (mock setup).
I'm told that you can expose SF through an API at some security risk. I'd love to find more about THAT.
There are a lot of testing methods out there i.e. blackbox, graybox, unit, functional, regression etc.
Obviously, a project cannot take on all testing methods. So I asked this question to gain an idea of what test methods to use and why should I use them. You can answer in the following format:
Test Method - what you use it on
e.g.
Unit Testing - I use it for ...(blah, blah)
Regression Testing - I use it for ...(blah, blah)
I was asked to engage into TDD and of course I had to research testing methods. But there is a whole plethora of them and I don't know what to use (because they all sound useful).
1. Unit Testing is used by developers to ensure unit code he wrote is correct. This is usually white box testing as well as some level of black box testing.
2. Regression Testing is a functional testing used by testers to ensure that new changes in system has not broken any of existing functionality
3. Functional testing is testing conducted on a complete, integrated system to evaluate the system's compliance with its specified requirements. Functionality testing falls within the scope of black box testing, and as such, should require no knowledge of the inner design of the code or logic
.
This Test-driven development and Feature Driven Development wiki articles will be of great help for you.
For TDD you need to follow following process:
Document feature (or use case) that
you need to implement or enhance
in your application that
currently does not exists.
Write set of functional test
cases that can ensure above
feature (from step 1) works. You may need to
write multiple test cases for
above feature to test all different
possible work flows.
Write code to implement above feature (from step 1).
Test this code using test cases you
had written earlier (in step 2). The actual
testing can be manual but I would recommend to create automated tests
if possible.
If all test cases pass, you are good to
go. If not, you need to update code (go back to step 3)
so as to make the test case pass.
TDD is to ensure that functional test cases which were written before you coded should work and does not matter how code was implemented.
There is no "right" or "wrong" in testing. Testing is an art and what you should choose and how well it works out for you depends a lot from project to project and your experience.
But as a professional Test Expert my suggestion is that you have a healthy mix of automated and manual testing.
(Examples below are in PHP but you can easily find the correct examples for what ever langauge/framework you are using)
AUTOMATED TESTING
Unit Testing
Use PHPUnit to test your classes, functions and interaction between them.
http://phpunit.sourceforge.net/
Automated Functional Testing
If it's possible you should automate a lot of the functional testing. Some frame works have functional testing built into them. Otherwise you have to use a tool for it. If you are developing web sites/applications you might want to look at Selenium.
http://www.webinade.com/web-development/functional-testing-in-php-using-selenium-ide
Continuous Integration
Use CI to make sure all your automated tests run every time someone in your team makes a commit to the project.
http://martinfowler.com/articles/continuousIntegration.html
MANUAL TESTING
As much as I love automated testing it is, IMHO, not a substitute for manual testing. The main reason being that an automated can only do what it is told and only verify what it has been informed to view as pass/fail. A human can use it's intelligence to find faults and raise questions that appear while testing something else.
Exploratory Testing
ET is a very low cost and effective way to find defects in a project. It take advantage of the intelligence of a human being and a teaches the testers/developers more about the project than any other testing technique i know of. Doing an ET session aimed at every feature deployed in the test environment is not only an effective way to find problems fast, but also a good way to learn and fun!
http://www.satisfice.com/articles/et-article.pdf
This answer is (almost) identical to one that I gave to another question. Check out that question since it had some other good answers that might help you.
How can we decide which testing method can be used?
I usually do the following things:
Page consistency in case of multi-page web sties.
Testing the database connections.
Testing the functionalities that can be affected by the change I just made.
I test functions with sample input to make sure they work fine (especially those that are algorithm-like).
In some cases I implement features very simply hard-coding most of the settings then implement the settings later, testing after implementing every setting.
Most of these apply to applications, too.
Well before going to the answer i would like to clear testing concept about multiple methods.
There are six main testing types which cover all most all testing methods.
Black Box Testing
White Box Testing
Grey Box Testing
Functional Testing
Integration Testing
Usability Testing
Almost all Testing methods lies under these types, you can also use some testing method in multiple types like you can use Smoke testing in black box or white box approach on the basis of resources available to test.
So for testing a web site completely you need to use at least following testing methods on the basis of resources available to test. These are at least methods which should be used to test a web site, but there may be some more imp methods on the basic of nature of website.
Requirement Testing
Smock Testing
System Testing
Integration Testing
Regression Testing
Security Testing
Performance & Load Testing
Deployment Testing
You should at least use all of above (8) testing methods to test a web site no matter what testing type you are focusing. You can automate you test in some areas and you can do this manually it all depends upon the resources availability.
There is specifically no hard and fast rule to follow any testing type or any method. As you know "Testing Is An ART" so art don't have rules or boundaries. Its totally up to you What you use to test and how.......
Hope you got the answer of question.
Selenium is very good for testing websites.
The answer depends on the Web framework used (if any). Django for example has built-in testing functions.
For PHP (or functional web testing), SimpleTest is pretty good and well... simple. It support Unit Testing (PHP only) and Web Testing. Tests can run in the IDE (Eclipse), or in the browser (meaning on your server).
The other answers posted so far focus on unit/functional/performance/etc. testing, and they are all reasonable.
However, one the key questions you should ask is, "how effective is my testing?".
This is often answered with test coverage tools, that determine which parts of your application actually get exercised by some set of tests. The ideal test coverage tool lets you test your application by any method you can imagine (including all the standard answers above) and will then report what part and what percentage of your code was exercised. Most importantly, it will tell you what code you did not exercise. You can then inspect that code and decide if more testing is warranted, or if you don't care. If the untested code has to do with "disk full error handling" and you belive that 1TB disks are common, you might decide to ignore that. If the untested code is the input validation logic leading to SQL queries, you might decide that you must test that logic to ensure that no SQL injection attacks can occur.
What test coverage tools let you do it to make a rational decision that you have tested adequately, using data about what parts of your code has been exercised. So regardless of how you test, best practices indicates you should also do test coverage analysis.
Test coverage tools can be obtained from a variety of sources. SD provides a family of test coverage tools that handle C, C++, Java, C#, PHP and COBOL, all of which are used to support web site testing in various ways.
Recently I've came up with the question is it worth at all to spent development time to generate automatic unit test for web based projects? I mean it seems useless at some point because at some point those projects are oriented on interactions with users/clients, so you cannot anticipate the whole possible set of user action so you be able to check the correctness of content showed. Even regression test can hardly be done. So I'm very eager to know to know the opinion of other experienced developers.
Selenium have a good web testing framework
http://seleniumhq.org/
Telerik are also in the process of developing one for web app testing.
http://www.telerik.com/products/web-ui-test-studio.aspx
You cannot anticipate the whole
possible set of user action so you be
able to check the correctness of
content showed.
You can't anticipate all the possible data your code is going to be handed, or all the possible race conditions if it's threaded, and yet you still bother unit testing. Why? Because you can narrow it down a hell of a lot. You can anticipate the sorts of pathological things that will happen. You just have to think about it a bit and get some experience.
User interaction is no different. There are certain things users are going to try and do, pathological or not, and you can anticipate them. Users are just inputting particularly imaginative data. You'll find programmers tend to miss the same sorts of conditions over and over again. I keep a checklist. For example: pump Unicode into everything; put the start date after the end date; enter gibberish data; put tags in everything; leave off the trailing newline; try to enter the same data twice; submit a form, go back and submit it again; take a text file, call it foo.jpg and try to upload it as a picture. You can even write a program to flip switches and push buttons at random, a bad monkey, that'll find all sorts of fun bugs.
Its often as simple as sitting someone down who's unfamiliar with the software and watching them use it. Fight the urge to correct them, just watch them flounder. Its very educational. Steve Krug refers to this as "Advanced Common Sense" and has an excellent book called "Don't Make Me Think" which covers cheap, simple user interaction testing. I highly recommend it. It's a very short and eye opening read.
Finally, the client themselves, if their expectations are properly prepared, can be a fantastic test suite. Be sure they understand its a work in progress, that it will have bugs, that they're helping to make their product better, and that it absolutely should not be used for production data, and let them tinker with the pre-release versions of your product. They'll do all sorts of things you never thought of! They'll be the best and most realistic testing you ever had, FOR FREE! Give them a very simple way to report bugs, preferably just a one button box right on the application which automatically submits their environment and history; the feedback box on Hiveminder is an excellent example. Respond to their bugs quickly and politely (even if its just "thanks for the info") and you'll find they'll be delighted you're so responsive to their needs!
Yes, it is. I just ran into an issue this week with a web site I am working on. I just recently switched-out the data access layer and set up unit tests for my controllers and repositories, but not the UI interactions.
I got bit by a pretty obvious bug that would have been easily caught if I had integration tests. Only through integration tests and UI functionality tests do you find issues with the way different tiers of the application interact with one another.
It really depends on the structure and architecture of your web application. If it contains an application logic layer, then that layer should be easy to unit test with automating tools such as Visual Studio. Also, using a framework that has been designed to enable unit testing, such as ASP.NET MVC, helps alot.
If you're writing a lot of Javascript, there have been a lot of JS testing frameworks that have come around the block recently for unit testing your Javascript.
Other than that, testing the web tier using something like Canoo, HtmlUnit, Selenium, etc. is more a functional or integration test than a unit test. These can be hard to maintain if you have the UI change a lot, but they can really come in handy. Recording Selenium tests is easy and something you could probably get other people (testers) to help you create and maintain. Just know that there is a cost associated with maintaining tests, and it needs to be balanced out.
There are other types of testing that are great for the web tier - fuzz testing especially, but a lot of the good options are commercial tools. One that is open source and plugs into Rails is called Tarantula. Having something like that at the web tier is a nice to have run in a continuous integration process and doesn't require much in the form of maintenance.
Unit tests make sense in TDD process. They do not have much value if you don't do test-first development. However the acceptance test are a big thing for quality of the software. I'd say that acceptance test is a holy grail of the development. Acceptance tests show whether the application satisfies the requirements. How do I know when to stop developing the feature --- only when all my acceptance test pass. Automation of acceptance testing a big thing because I do not have to do it all manualy each time I make changes to the application. After months of development there can be hundreds of test and it becomes unfeasible (sometime impossible) to run all the test manually. Then how do I know if my application still works?
Automation of acceptance tests can be implemented with use of xUnit test frameworks, which makes a confusion here. If I create an acceptance test using phpUnit or httpUnit is it a unit test? My answer is no. It does not matter what tool I use to create and run test. Acceptance test is the one that show whether the features is working IAW requirements. Unit test show whether a class (or function) satisfies the developer's implementation idea. Unit test has no value for the client (user). Acceptance test has a lot of value to the client (and thus to developer, remember Customer Affinity)
So I strongly recommend creating automated acceptance tests for the web application.
The good frameworks for the acceptance test are:
Sahi (sahi.co.in)
Silenium
Simpletest (I't a unit-test framework for php, but includes the browser object that can be used for acceptance testing).
However
You have mentioned that web-site is all about user interaction and thus test automation will not solve the whole problem of usability. For example: testing framework shows that all tests pass, however the user cannot see the form or link or other page element due to accidental style="display:none" in the div. The automated tests pass because the div is present in the document and test framework can "see" it. But the user cannot. And the manual test would fail.
Thus, all web-applications needs manual testing. The automated test can reduce the test workload drastically (80%), but manual test are as well significant for the quality of the resulting software.
As for the Unit testing and TDD -- it make the code quality. It is beneficial to the developers and for the future of the project (i.e. for projects longer that a couple of month). However TDD requires skill. If you have the skill -- use it. If you don't consider gaining the skill, but mind the time it will take to gain. It usually takes about 3 - 6 month to start creating a good Unit tests and code. If you project will last more that a year, I recommend studding TDD and investing time in proper development environment.
I've created a web test solution (docker + cucumber); it's very basic and simple, so easy to understand and modify / improve. It lies in the web directory;
my solution: https://github.com/gyulaweber/hosting_tests