yuehei / task.js

A beautiful way to control your task flow, simple and powerful

task.js

A beautiful way to control your task flow, simple and powerful. take a look at Demo and Automatic test

Usage

Think of the following code

setTimeout(function () {
    // do something
    setTimeout(function () {
        // do something
        setTimeout(function () {
            // do something
            setTimeout(function () {
                // do something
                setTimeout(function () {
                  // do something
                },1000)
            },1000)
        },1000)
    },1000)
},1000);

By this tiny script task.js, you just need this

task()
.sleep(1000)
.run(function () {})
.sleep(1000)
.run(function () {})
.sleep(1000)
.run(function () {})
.sleep(1000)
.run(function () {})
.sleep(1000)
.run(function () {})
.start();

Instance method

1. run(fn)

   run function

   params:

   fn - the function to be executed, the value fn returned will be the parammeter of the next fn. so it is easy to break a complex operation to mutiple simple tasks using task.js

   returns:

   the task object itself

2. sleep(time)

   sleep some time

   params:

   time - the waiting time to perform the next operation. time can be a function or number, if time is function, it use the returned value as the waiting time,and it will try to convert return value to number, it's parameter is the return value from last "run" function. so, it is easily to dynamiclly generate the timeout value according to the result of last opteration.

   returns:

   the task object itself

3. start()

   start execute task

   params:

   this function takes no params

   returns:

   this function has no return value

4. cancel()

   stop execute task, the interrupt handler will be executed, see interrupt method

   params:

   this function takes no params

   returns:

   this function has no return value

5. progress(fn)

   set the callback function to execute after each small task is executed

   fn - the callback function. this function will be passed three parameters. step - the index of "run" function, totalStep - the total step of the task, currentRepeat - the index of repeat, totalRepeat - total repeat times.

   returns:

   the task object itself

6. done(fn)

   set callback function when task is done, if the task is protected, that means there's no assertion errors. if task isn't protected, that means the task has finished.

   params:

   fn - the callback function when task is done

   returns:

   the task object itself

7. interrupt(fn)

   set callback function when task is interrupted. when the task is protected and there is assertion fail, the task will be interrupted.

   params:

   fn - the callback function when task is done. detail - fn will be fulfilled with error details.

   returns:

   the task object itself

8. repeat(times)

   set the times to repeat to do the task

   params:

   times - the times to repeat to do the task

   returns:

   the task object itself

9. assertEquals([fn,fn,...])

   assert parammeters or it's return value is equal

   params:

   fn - the function to be executed. it's parameter is the return value from last "run" function.

   returns:

   the task object itself

10. assertNotEquals([fn,fn,...])

    assert parammeters or it's return value isn't equal

    params:

    fn - the function to be executed. it's parameter is the return value from last "run" function.

    returns:

    the task object itself

11. assertFalse(fn)

    assert parammeters or it's return value is false

    params:

    fn - the function to be executed. it's parameter is the return value from last "run" function.

    returns:

    the task object itself

12. assertTrue(fn)

    assert parammeters or it's return value is true

    params:

    fn - the function to be executed. it's parameter is the return value from last "run" function.

    returns:

    the task object itself

13. protect()

    protect the queue, once any assertion failed, the task is finished. this is the default behaviour.

    params:

    this function takes no params

    returns:

    this function returns nothing

14. unprotect()

    unprotect the queue, ignore the assertion failed event, continue to execute the rest task.

    params:

    this function takes no params

    returns:

    this function returns nothing

Static method

onAssertionFail

Hook the assertion fail event

task.onAssertionFail = function (err) {
    // err object contains error info
    // or you can just throw it
    throw err;
}

FAQ

What will happen if assertion failed?

it follows the following routine

1. if onAssertionFail is defined, just let onAssertionFail handle it
2. if window has console object, and console has assert method, let window.console handle it
3. if no handlers, just throw an AssertionFail error
4. stop the rest tasks

Show me some examples

var i=1;
var result = 0;

task().run(function () {
    result = result + i;
    i = i + 1;
}).repeat(100).done(function () {
    console.log(result); // output 5050
}).start();

var i=1;
var result = 0;

task().run(function () {
    result = result + i;
    i = i + 1;
}).sleep(500).run(function () {
    console.log(result); // output result every 500ms
}).repeat(100).done(function () {
    console.log(result); // output 5050
});
}).start();