Initial commit

pool_test.go

@@ -0,0 +1,104 @@
+package pool_test
+
+import (
+	"context"
+	"errors"
+	"testing"
+	"time"
+
+	"github.com/jackc/pool"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestPoolGet_CreatesResourceWhenNoneAvailable(t *testing.T) {
+	createCalls := 0
+	createFunc := func() (interface{}, error) {
+		createCalls += 1
+		return createCalls, nil
+	}
+	pool := pool.New(createFunc)
+
+	res, err := pool.Get(context.Background())
+	require.NoError(t, err)
+	assert.Equal(t, 1, res)
+
+	pool.Return(res)
+}
+
+func TestPoolGet_ReturnsErrorFromFailedResourceCreate(t *testing.T) {
+	errCreateFailed := errors.New("create failed")
+	createFunc := func() (interface{}, error) {
+		return nil, errCreateFailed
+	}
+	pool := pool.New(createFunc)
+
+	res, err := pool.Get(context.Background())
+	assert.Equal(t, errCreateFailed, err)
+	assert.Nil(t, res)
+}
+
+func TestPoolGet_ReusesResources(t *testing.T) {
+	createCalls := 0
+	createFunc := func() (interface{}, error) {
+		createCalls += 1
+		return createCalls, nil
+	}
+	pool := pool.New(createFunc)
+
+	res, err := pool.Get(context.Background())
+	require.NoError(t, err)
+	assert.Equal(t, 1, res)
+
+	pool.Return(res)
+
+	res, err = pool.Get(context.Background())
+	require.NoError(t, err)
+	assert.Equal(t, 1, res)
+
+	pool.Return(res)
+
+	assert.Equal(t, 1, createCalls)
+}
+
+func TestPoolGet_ContextAlreadyCanceled(t *testing.T) {
+	createFunc := func() (interface{}, error) {
+		panic("should never be called")
+	}
+	pool := pool.New(createFunc)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	res, err := pool.Get(ctx)
+	assert.Equal(t, context.Canceled, err)
+	assert.Nil(t, res)
+}
+
+func TestPoolGet_ContextCanceledDuringCreate(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+
+	createCalls := 0
+
+	createFunc := func() (interface{}, error) {
+		cancel()
+		time.Sleep(1 * time.Second)
+		createCalls += 1
+		return createCalls, nil
+	}
+	pool := pool.New(createFunc)
+
+	res, err := pool.Get(ctx)
+	assert.Equal(t, context.Canceled, err)
+	assert.Nil(t, res)
+}
+
+func TestPoolReturnPanicsIfResourceNotPartOfPool(t *testing.T) {
+	createCalls := 0
+	createFunc := func() (interface{}, error) {
+		createCalls += 1
+		return createCalls, nil
+	}
+	pool := pool.New(createFunc)
+
+	assert.Panics(t, func() { pool.Return(42) })
+}