Life-Cycle Methods

Last updated 11 days ago

Before and After Specs

If you are familiar with xUnit style frameworks, the majority of them provide a way to execute functions before and after every single test case or spec in BDD. This is a great way to keep your tests DRY (Do not repeat yourself)! TestBox provides the beforeEach() and afterEach() methods that each take in a closure as their argument that receive the name of the spec that's about to be executed or just executed. As their names indicate, they execute before a spec and after a spec in a related describe block.

describe("A spec (with setup and tear-down)", function() {
beforeEach(function( currentSpec ) {
coldbox = 22;
application.wirebox = new coldbox.system.ioc.Injector();
});
afterEach(function( currentSpec ) {
coldbox = 0;
structDelete( application, "wirebox" );
});
it("is just a function, so it can contain any code", function() {
expect( coldbox ).toBe( 22 );
});
it("can have more than one expectation and talk to scopes", function() {
expect( coldbox ).toBe( 22 );
expect( application.wirebox.getInstance( 'MyService' ) ).toBeComponent();
});
});

Around Specs

The aroundEach() life-cycle method will completely wrap your spec in another closure. This is an elegant way for you to provide a complete around AOP advice to a specification. You can use it to surround the execution in transaction blocks, ORM rollbacks, logging, and so much more. This life-cycle method will decorate ALL specs within a single suite and any children suites. The method signature is below:

aroundEach( function( spec, suite ){
// execute the spec
arguments.spec.body();
} );

The method receives a structure of data representing the spec. This contains the following elements:

  • body : The actual closure for the spec that you will use to execute within it.

  • labels : The labels used in the spec

  • name : The name of the spec

  • order : The order of execution of the spec

  • skip : The skip flag or closure that determines if the spec runs

The method also receives a structure of metadata about the suite this spec is contained in. It has information about life-cycle closures, async information, names, parents, etc. Here is a very practical example of creating and around each closure to provide rollbacks for specs:

aroundEach( function( spec, suite ){
transaction action="begin"{
try{/
// execute the spec
arguments.spec.body();
} catch( Any e ){
rethrow;
} finally{
transaction action="rollback";
}
}
} );

This simple around each life-cycle closure will rollback ALL my spec's executions even if they throw exceptions.

Annotations

TestBox since v2.3.0 also allows you to declare life-cycle methods via annotations. Please see our Annotations section for more information.

Lifecycle Nesting Order

When you use beforeEach(), afterEach(), and aroundEach() at the same time, there is a specific order they fire in. For a given describe block, they will fire in this order. Remember, aroundEach() is split into two parts-- the half of the method before you call spec.body() and the second half of the method.

  1. beforeEach

  2. aroundEach (first half)

  3. it() (the spec.body() call)

  4. aroundEach (second half)

  5. afterEach()

Here's an example:

describe( 'my describe', function(){
beforeEach( function( currentSpec ){
// I run first
} );
aroundEach( function( spec, suite ){
// I run second
arguments.spec.body();
// I run fourth
});
afterEach( function( currentSpec ){
// I run fifth
} );
it( 'my it', function(){
// I run third
} );
} );

If there are more than one it() blocks, the process repeats for each one. Steps 1, 2, 4, 5 will wrap every single it().

When you nest more than one describe block inside the other, the before/around/after order is the same but drills down to the innermost describe and then bubbles back up. That means the outermost beforeEach() starts and we end on the outermost afterEach().

Here's what an example flow would look like that had before/after/around specified in two levels of describes with a single it() in the inner most describe.

  1. Outermost beforeEach() call

  2. Innermost beforeEach() call

  3. Outermost aroundEach() call (first half)

  4. Innermost aroundEach() call (first half)

  5. The it() block

  6. Innermost aroundEach() calls (second half)

  7. Outermost aroundEach() call (second half)

  8. Innermost afterEach() call

  9. Outermost afterEach() call

This works regardless of the number of levels and can obviously have many permutations, but the basic order is still the same. Before/around/after and starting at the outside working in, and back out again. This process happens for every single spec or it() block. This is as opposed to the beforeAll() and afterAll() method which only run once for the entire CFC regardless of how many specs there are.