go-by-test/wallet/wallet_test.go
2024-09-11 11:49:10 +02:00

75 lines
1.4 KiB
Go

package wallet
import (
"fmt"
"testing"
)
func ExampleWallet() {
wallet := Wallet{10}
wallet.Deposit(10)
fmt.Printf("The balance is %s\n", wallet.Balance())
err := wallet.Withdraw(10)
if err != nil {
fmt.Println(err)
}
fmt.Printf("The balance is %s\n", wallet.Balance())
// Output: The balance is 20 BTC
// The balance is 10 BTC
}
func TestWallet(t *testing.T) {
t.Run("deposit", func(t *testing.T) {
wallet := Wallet{}
wallet.Deposit(10)
assertBalance(t, wallet, Bitcoin(10))
})
t.Run("withdraw", func(t *testing.T) {
wallet := Wallet{balance: Bitcoin(20)}
err := wallet.Withdraw(10)
assertNoError(t, err)
assertBalance(t, wallet, Bitcoin(10))
})
t.Run("withdraw insufficient funds", func(t *testing.T) {
startingBalance := Bitcoin(20)
wallet := Wallet{balance: startingBalance}
err := wallet.Withdraw(100)
assertError(t, err, ErrInsufficientFunds)
assertBalance(t, wallet, startingBalance)
})
}
func assertBalance(t testing.TB, wallet Wallet, want Bitcoin) {
t.Helper()
got := wallet.Balance()
if got != want {
t.Errorf("got %q, want %q", got, want)
}
}
func assertError(t testing.TB, got error, want error) {
t.Helper()
if got == nil {
t.Fatal("didn't get an error but wanted one")
}
if got != want {
t.Errorf("got %q, want %q", got, want)
}
}
func assertNoError(t testing.TB, got error) {
t.Helper()
if got != nil {
t.Fatal("get an error but didn't want one")
}
}