Add MapStore which implements the Storer interface

Adds the Puppy, Storer and MapStore type definitions. MapStore implements
the Storer interface and supplies a NewMapStore factory function.

- Uuid increment is handled internally by MapStore Create
- Read will return an empty Puppy struct if provided uuid doesn't exist
- Update returns a bool whether a matching identifier was modified
- Destroy returns a bool whether a matching identifier was modified

Lab 06 (#537)

06_puppy/patrickmarabeas/mapStore.go

@@ -0,0 +1,51 @@
+package main
+
+// NewMapStore returns a pointer to a new instance of the MapStore struct which implements the Storer interface.
+func NewMapStore() Storer {
+	return &MapStore{
+		uuid:  0,
+		store: map[int]Puppy{},
+	}
+}
+
+// Create increments the uuid and adds the provided Puppy struct to the store with this identifier.
+func (store *MapStore) Create(puppy Puppy) int {
+	puppy.ID = store.uuid
+	store.store[puppy.ID] = puppy
+	store.uuid++
+
+	return puppy.ID
+}
+
+// Read returns the puppy matching the provided uuid.
+// An empty Puppy struct is returned if the identifier does not exist.
+func (store *MapStore) Read(id int) Puppy {
+	if _, ok := store.store[id]; ok {
+		return store.store[id]
+	}
+
+	return Puppy{}
+}
+
+// Update modifies the puppy matching the provided uuid in the store with the provided Puppy struct.
+// It returns a bool whether a matching identifier was modified or not.
+func (store *MapStore) Update(id int, puppy Puppy) bool {
+	if _, ok := store.store[id]; !ok {
+		return false
+	}
+
+	puppy.ID = id
+	store.store[id] = puppy
+	return true
+}
+
+// Destroy removes the puppy matching the provided uuid from the store.
+// It returns a bool whether a matching identifier was deleted or not.
+func (store *MapStore) Destroy(id int) bool {
+	if _, ok := store.store[id]; !ok {
+		return false
+	}
+
+	delete(store.store, id)
+	return true
+}

06_puppy/patrickmarabeas/store_test.go

@@ -0,0 +1,86 @@
+package main
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/suite"
+)
+
+type StoreSuite struct {
+	suite.Suite
+	store Storer
+}
+
+func (suite *StoreSuite) TestCreate() {
+	a := assert.New(suite.T())
+	id := suite.store.Create(Puppy{Breed: "Wolf", Color: "Grey", Value: "450"})
+
+	a.Equal(id, 0)
+}
+
+func (suite *StoreSuite) TestCreateSecond() {
+	a := assert.New(suite.T())
+	id := suite.store.Create(Puppy{Breed: "Boxer", Color: "Brown", Value: "300"})
+
+	a.Equal(id, 1)
+}
+
+func (suite *StoreSuite) TestRead() {
+	a := assert.New(suite.T())
+	data := suite.store.Read(0)
+
+	a.Equal(data, Puppy{ID: 0, Breed: "Wolf", Color: "Grey", Value: "450"})
+}
+
+func (suite *StoreSuite) TestReadNonExistent() {
+	a := assert.New(suite.T())
+	success := suite.store.Read(100)
+
+	a.Equal(success, Puppy{})
+}
+
+func (suite *StoreSuite) TestUpdate() {
+	a := assert.New(suite.T())
+	success := suite.store.Update(0, Puppy{Breed: "Doberman", Color: "Black", Value: "500"})
+	data := suite.store.Read(0)
+
+	a.Equal(success, true)
+	a.Equal(data, Puppy{ID: 0, Breed: "Doberman", Color: "Black", Value: "500"})
+}
+
+func (suite *StoreSuite) TestUpdateNonExistent() {
+	a := assert.New(suite.T())
+	success := suite.store.Update(100, Puppy{Breed: "Doberman", Color: "Black", Value: "500"})
+
+	a.Equal(success, false)
+}
+
+func (suite *StoreSuite) TestDestroy() {
+	a := assert.New(suite.T())
+	success := suite.store.Destroy(1)
+	data := suite.store.Read(1)
+
+	a.Equal(success, true)
+	a.Equal(data, Puppy{})
+}
+
+func (suite *StoreSuite) TestDestroyNonExistent() {
+	a := assert.New(suite.T())
+	success := suite.store.Destroy(100)
+
+	a.Equal(success, false)
+}
+
+func (suite *StoreSuite) TestIdIncrementOnDelete() {
+	a := assert.New(suite.T())
+	id := suite.store.Create(Puppy{Breed: "Greyhound", Color: "Light Brown", Value: "700"})
+	suite.store.Destroy(id)
+	newId := suite.store.Create(Puppy{Breed: "Greyhound", Color: "Light Brown", Value: "700"})
+
+	a.Equal(newId, 3)
+}
+
+func TestStore(t *testing.T) {
+	suite.Run(t, &StoreSuite{store: NewMapStore()})
+}

06_puppy/patrickmarabeas/types.go

@@ -0,0 +1,20 @@
+package main
+
+type Puppy struct {
+	ID    int
+	Breed string
+	Color string
+	Value string
+}
+
+type Storer interface {
+	Create(puppy Puppy) int
+	Read(ID int) Puppy
+	Update(ID int, puppy Puppy) bool
+	Destroy(ID int) bool
+}
+
+type MapStore struct {
+	uuid  int
+	store map[int]Puppy
+}