From d73528bd8b3bf57b3113df319d91040499ab8064 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vin=C3=ADcius=20Garcia?= <vingarcia00@gmail.com>
Date: Wed, 3 Aug 2022 21:21:31 -0300
Subject: [PATCH] Add tests for the .Close() method

---
 internal_mocks.go |  9 +++++++++
 ksql_test.go      | 51 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 60 insertions(+)

diff --git a/internal_mocks.go b/internal_mocks.go
index e022a92..2fae9b9 100644
--- a/internal_mocks.go
+++ b/internal_mocks.go
@@ -40,3 +40,12 @@ func (m mockTx) Rollback(ctx context.Context) error {
 func (m mockTx) Commit(ctx context.Context) error {
 	return m.CommitFn(ctx)
 }
+
+// mockCloser mocks the io.Closer interface
+type mockCloser struct {
+	CloseFn func() error
+}
+
+func (m mockCloser) Close() error {
+	return m.CloseFn()
+}
diff --git a/ksql_test.go b/ksql_test.go
index 1f3b579..a7c09d9 100644
--- a/ksql_test.go
+++ b/ksql_test.go
@@ -1,6 +1,8 @@
 package ksql
 
 import (
+	"fmt"
+	"io"
 	"testing"
 
 	tt "github.com/vingarcia/ksql/internal/testtools"
@@ -38,3 +40,52 @@ func TestNewAdapterWith(t *testing.T) {
 		tt.AssertNotEqual(t, err, nil)
 	})
 }
+
+func TestClose(t *testing.T) {
+	t.Run("should close the adapter if it implements the io.Closer interface", func(t *testing.T) {
+		c := DB{
+			db: struct {
+				DBAdapter
+				io.Closer
+			}{
+				DBAdapter: mockDBAdapter{},
+				Closer: mockCloser{
+					CloseFn: func() error {
+						return nil
+					},
+				},
+			},
+		}
+
+		err := c.Close()
+		tt.AssertNoErr(t, err)
+	})
+
+	t.Run("should exit normally if the adapter does not implement the io.Closer interface", func(t *testing.T) {
+		c := DB{
+			db: mockDBAdapter{},
+		}
+
+		err := c.Close()
+		tt.AssertNoErr(t, err)
+	})
+
+	t.Run("should report an error if the adapter.Close() returns one", func(t *testing.T) {
+		c := DB{
+			db: struct {
+				DBAdapter
+				io.Closer
+			}{
+				DBAdapter: mockDBAdapter{},
+				Closer: mockCloser{
+					CloseFn: func() error {
+						return fmt.Errorf("fakeCloseErrMsg")
+					},
+				},
+			},
+		}
+
+		err := c.Close()
+		tt.AssertErrContains(t, err, "fakeCloseErrMsg")
+	})
+}