martinsson’s gists

martinsson / BetRepositoryContract.ts

Created June 7, 2024 07:58


	// inject a function that provides the interface under contract testing
	function betRepositoryContract(getRepository: () => BetRepository) {

	test('register a bets', async () => {
	expect(true).toEqual(false);
	})

	test('bets outside range are not retrieved', async () => {
	expect(true).toEqual(false);

martinsson / create_connection.go

Last active October 4, 2020 22:36

Error handling in go 3/3: the if statements have gone away. Finally!

	tenantID, err1 := store.GetParameter("TENANT_ID")
	clientID, err2 := store.GetParameter("CLIENT_ID")
	clientSecret, err3 := store.GetParameter("CLIENT_SECRET")

	globalErr := multierr.Combine(err1, err2, err3)
	return connection{
	tenantID,
	clientID,
	clientSecret,
	}, globalErr

martinsson / create_connection.go

Last active October 4, 2020 22:36

Error handling in GO 2/3 : A better version of the error handling. No more if statement per variable

	tenantID, err1 := store.GetParameter("TENANT_ID")
	clientID, err2 := store.GetParameter("CLIENT_ID")
	clientSecret, err3 := store.GetParameter("CLIENT_SECRET")

	globalErr := multierr.Combine(err1, err2, err3)
	if globalErr != nil {
	fmt.Print(globalErr)
	return nil, globalErr
	}

martinsson / create_connection.go

Last active October 4, 2020 22:35

Error handling trick in GoLang 1/3 : CombineErrors

	func createConnection(store Store) (Connection, error) {

	tenantID, err := store.GetParameter("TENANT_ID")
	if err != nil {
	fmt.Print("Unable to get TENANT_ID from parameter store")
	return nil, err
	}
	clientID, err := store.GetParameter("CLIENT_ID")
	if err != nil {
	fmt.Print("Unable to get CLIENT_ID from parameter store")

martinsson / TestableDependency.java

Last active January 3, 2019 15:15

Using a instance method as a proxy to the real method we can fake it to avoid calling the real method

	// this method is fakable
	public String getTranslation(String key, Locale locale) {
	return getTranslationOld(key, locale);
	}

	/**
	* @deprecated use instance method instead
	*/
	public static String getTranslationOld(String key, Locale locale) {
	Object keys = getTranslationMap().get(locale.toString());

martinsson / LazyInitialiserDependency.java

Last active January 3, 2019 15:11

The static initialiser has been replace by a lazy initialiser, allowing for loading the class without provoking a query to the database.


	public class LazyInitialiserDependency {

	private static Map<String, Object> translationMap;

	// no more static initaliser, the class is mockable, though we'll have to go further by
	// adding a version of getTranslation as an instance method if we want to mock it

	// this static method is called by the class you'd like to test
	public static String getTranslation(String key, Locale locale) {

martinsson / UntestableDependency.java

Last active January 3, 2019 15:12

Full code of an offending class using a database query in it's static initialiser


	public class UnTestableDependency {

	private static Map<String, Object> translationMap;

	static {
	translationMap = HibernateUtil.executeQuery("Select ...");
	}

	// this static method is called by the class you'd like to test

martinsson / UntestableDependency.java

Created January 3, 2019 14:56

Untestable static initialiser

	private static Map<String, Object> translationMap;

	static {
	translationMap = HibernateUtil.executeQuery("Select ...");
	}

martinsson / fizzbuzz.idr

Created July 3, 2018 22:18

FizzBuzz as an alias for a tuple

	\|\|\| the type Fizzbuzz is just an alias for the tuple of FizzT and BuzzT
	Fizzbuzz: Nat -> Type
	Fizzbuzz n = (FizzT n, BuzzT n)

martinsson / fizzbuzz.idr

Last active July 3, 2018 21:11

the whole first solution


	\|\|\| proof that k is divisible by 3, can only be called when the compiler can verify it
	IsFizz : (k : Nat) -> Type
	IsFizz k = (modNatNZ k 3 SIsNotZ = 0) -- modNatNZ is modulos for natural numbers except for 0.
	-- SIsNotZ is also a proof about k in this case. Compiler will fail if k is not greater than 0

	IsBuzz : Nat -> Type
	IsBuzz k = (modNatNZ k 5 SIsNotZ = 0)

	\|\|\| There are four constructors : Fizz, Buzz, FizzBuzz, and Normal.

Johan Martinsson martinsson