Testing Go code

Here’s a cute way to test Go code. From How To Implement Domain-Driven Design (DDD) in Golang.
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package memory
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import (
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  "testing"
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  "ddd/aggregate"
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  "ddd/domain/customer"
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  "github.com/google/uuid"
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)
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func TestMemory_GetCustomer(t *testing.T) {
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  type testCase struct {
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    expectedErr error
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    name        string
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    id          uuid.UUID
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  }
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  // Create a fake customer to add to repository
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  cust, err := aggregate.NewCustomer("Percy")
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  if err != nil {
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    t.Fatal(err)
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  }
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  id := cust.GetID()
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  // Create the repo to use, and add some test Data to it for testing
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  // Skip Factory for this
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  repo := MemoryRepository{
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    customers: map[uuid.UUID]aggregate.Customer{
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      id: cust,
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    },
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  }
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  testCases := []testCase{
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    {
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      name:        "No Customer By ID",
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      id:          uuid.MustParse("f47ac10b-58cc-0372-8567-0e02b2c3d479"),
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      expectedErr: customer.ErrCustomerNotFound,
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    }, {
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      name:        "Customer By ID",
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      id:          id,
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      expectedErr: nil,
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    },
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  }
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  for _, tc := range testCases {
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    t.Run(tc.name, func(t *testing.T) {
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      _, err := repo.Get(tc.id)
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      if err != tc.expectedErr {
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        t.Errorf("Expected error %v, got %v", tc.expectedErr, err)
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      }
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    })
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  }
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}
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func TestMemory_AddCustomer(t *testing.T) {
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  type testCase struct {
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    name        string
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    cust        string
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    expectedErr error
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  }
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  testCases := []testCase{
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    {
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      name:        "Add Customer",
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      cust:        "Percy",
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      expectedErr: nil,
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    },
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  }
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  for _, tc := range testCases {
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    t.Run(tc.name, func(t *testing.T) {
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      repo := MemoryRepository{
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        customers: map[uuid.UUID]aggregate.Customer{},
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      }
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      cust, err := aggregate.NewCustomer(tc.cust)
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      if err != nil {
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        t.Fatal(err)
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      }
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      err = repo.Add(cust)
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      if err != tc.expectedErr {
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        t.Errorf("Expected error %v, got %v", tc.expectedErr, err)
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      }
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      found, err := repo.Get(cust.GetID())
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      if err != nil {
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        t.Fatal(err)
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      }
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      if found.GetID() != cust.GetID() {
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        t.Errorf("Expected %v, got %v", cust.GetID(), found.GetID())
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      }
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    })
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  }
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}