Unit Testing

Go to introduction to see information about Unit-testing

The example listed below show all the different functions to make a test pass or fail.

Error Message

At every example that will be shown below you will have a variable called: "errorMessage". This message is printed into the terminal when the test does not pass. The message is custom, so you can decide what it says. This feature might help to debug your failed code test.


The function "assert" checks if the given argument is "true". You will need this function if you I.E. want to check if one number is greater than another.

assert(true, errorMessage) // "errorMessage" is optional

Assert Equals

Checks if the two given value's are the same. You could use it to check if "x" equals "y", or check if "z" is of type: string. When these two values are the same, the test passes.

assert_equals(4, 4, errorMessage) // "errorMessage" is optional

Assert Exception

The "assert_exception" function checks if the functions that you called returns an exception. You might need this to check if your error handling works as intended.

assert_exception(error, errorMessage) // "errorMessage" is optional


Shown below is a function with one parameter, called "Double". When the function is called the parameter gets doubled and returned. Below the function is the test to test "Double"

double := fn(number) {
    return number * 2

doubleTest := fn() {
    result := double(2)
    expected := 4
    error := "Error -> expected: {expected}, got: {result}"
    assert_equals(result, excepted, error) // This will work!

Lets take a look at the test: "doubleTest". There are four lines, we go line by line. The first line calls the function that we want to test, and it stores its return value in a variable called: "result". The next line is very simple it is a variable declaration, where "excepted" gets assigned the value of "4". On the next line you see a variable called: "errorMessage", this is user-created message that gets printed in the terminal when the test does not pass. At the end, we see the actual test. It takes three arguments; the result; what is expected; and the optional error message.

In this case, the test passes because result (value is 4) is the same as expected (value is 4). The error message will not be shown.

doubleTest := fn() {
    result := double(2) // Which returns the integer of 4
    expected := 4
    errorMessage := "Error -> expected: {expected}, got: {result}"
    assert_equals(result, excepted, errorMessage) // This will work!

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