tester

The tester package contains functionality for registering and running tests with assertions.

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Package Functions

initialize()

Initializes the global testing environment if it hasn't been initialized yet.

Parameters None

Returns None

Example

import "tester"

tester::initialize()

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assert(condition, msg = "Assertion failed.")

Checks if a condition is true. If the condition is false, an error is thrown with the specified message.

Parameters

Type	Name	Description
boolean	condition	The condition to evaluate.
string	msg	The message to display if the assertion fails (optional, defaults to "Assertion failed.").

Returns None

Example

import "tester"

tester::assert(1 + 1 == 2, "basic math should work")
tester::assert("hello".size() == 5, "string size should be 5")

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assert_eq(actual, expected, msg = "")

Checks if actual equals expected. If they are not equal, an error is thrown with an informative message.

Parameters

Type	Name	Description
any	actual	The actual value.
any	expected	The expected value.
string	msg	An optional message to include in the failure output.

Returns None

Example

import "tester"

var result = [1, 2, 3].size()
tester::assert_eq(result, 3, "list should have 3 elements")

var greeting = "hello " + "world"
tester::assert_eq(greeting, "hello world", "string concatenation")

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test(f, name) (decorator)

Registers a function as a named unit test and returns it unchanged. Designed to be used as a @tester::test("name") decorator above a fn definition — the cleanest way to register tests.

Parameters

Type	Name	Description
lambda	f	The test function (injected automatically by the decorator).
string	name	The display name shown in test runner output.

Returns

Type	Description
lambda	The original function, unchanged, so it remains directly callable.

Example

import "tester"

@tester::test("math works")
fn test_math()
  tester::assert_eq(2 + 2, 4, "addition")
  tester::assert_eq(10 - 3, 7, "subtraction")
end

@tester::test("strings work")
fn test_strings()
  tester::assert_eq("hi".size(), 2, "string size")
  tester::assert("hello".contains("ell"), "substring check")
end

results = tester::run_tests()

The decorated function is still directly callable as test_math(), test_strings(), etc.

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register_test(name, t)

Registers a test function to the global test list. Prefer the @tester::test decorator for new code.

Parameters

Type	Name	Description
string	name	The name of the test.
lambda	t	The test function.

Returns None

Example

import "tester"

tester::initialize()

tester::register_test("math works", with () do
  tester::assert_eq(2 + 2, 4, "addition")
  tester::assert_eq(10 - 3, 7, "subtraction")
end)

tester::register_test("strings work", with () do
  tester::assert_eq("hi".size(), 2, "string size")
  tester::assert("hello".contains("ell"), "substring check")
end)

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run_test(name, test, results = [])

Runs a specific test, measures its duration, and adds the result to the results list.

Parameters

Type	Name	Description
string	name	The name of the test.
lambda	test	The test function to execute.
list	results	The list where test results are stored (optional, defaults to an empty list).

Returns None

Example

import "tester"

var results = []

tester::run_test("addition", with () do
  tester::assert_eq(1 + 1, 2, "1 + 1 should equal 2")
end, results)

tester::run_test("string length", with () do
  tester::assert_eq("kiwi".size(), 4, "kiwi has 4 characters")
end, results)

for r in results
  println r["name"] + ": " + (r["result"] ? "passed" : "failed")
end

---

run_tests()

Executes all registered tests and returns a list of test results, including the name, whether the test passed, and its duration.

Parameters None

Returns

Type	Description
list	A list of test result objects, each containing the name, result (boolean), and duration (milliseconds).

Example

import "tester"

tester::initialize()

tester::register_test("list operations", with () do
  var nums = [1, 2, 3, 4, 5]
  tester::assert_eq(nums.size(), 5, "list size")
  tester::assert_eq(nums.sum(), 15, "list sum")
  tester::assert_eq(nums.first(), 1, "first element")
  tester::assert_eq(nums.last(), 5, "last element")
end)

tester::register_test("string operations", with () do
  var s = "Hello, Kiwi!"
  tester::assert(s.contains("Kiwi"), "should contain 'Kiwi'")
  tester::assert_eq(s.upcase(), "HELLO, KIWI!", "upcase")
  tester::assert_eq(s.replace("Kiwi", "World"), "Hello, World!", "replace")
end)

tester::register_test("arithmetic", with () do
  tester::assert_eq(2 ** 8, 256, "exponentiation")
  tester::assert_eq(17 % 5, 2, "modulo")
  tester::assert(3.14 > 3, "float comparison")
end)

var results = tester::run_tests()

for r in results
  var status = r["result"] ? "passed" : "failed"
  println r["name"] + " [" + status + "] (" + r["duration"].to_string() + "ms)"
end