diff --git a/app_test.go b/app_test.go
index b20e0c455c..fcb623bdfb 100644
--- a/app_test.go
+++ b/app_test.go
@@ -499,17 +499,20 @@ func Test_App_Order(t *testing.T) {
 	app := New()
 
 	app.Get("/test", func(c *Ctx) error {
-		c.Write([]byte("1"))
+		_, err := c.Write([]byte("1"))
+		utils.AssertEqual(t, nil, err)
 		return c.Next()
 	})
 
 	app.All("/test", func(c *Ctx) error {
-		c.Write([]byte("2"))
+		_, err := c.Write([]byte("2"))
+		utils.AssertEqual(t, nil, err)
 		return c.Next()
 	})
 
 	app.Use(func(c *Ctx) error {
-		c.Write([]byte("3"))
+		_, err := c.Write([]byte("3"))
+		utils.AssertEqual(t, nil, err)
 		return nil
 	})
 
diff --git a/internal/go-ole/connect.go b/internal/go-ole/connect.go
index b2ac2ec67a..b910f0e329 100644
--- a/internal/go-ole/connect.go
+++ b/internal/go-ole/connect.go
@@ -44,8 +44,8 @@ func (c *Connection) Release() {
 
 // Load COM object from list of programIDs or strings.
 func (c *Connection) Load(names ...string) (errors []error) {
-	var tempErrors []error = make([]error, len(names))
-	var numErrors int = 0
+	var tempErrors = make([]error, len(names))
+	var numErrors = 0
 	for _, name := range names {
 		err := c.Create(name)
 		if err != nil {
diff --git a/internal/schema/decoder.go b/internal/schema/decoder.go
index 9d44822202..b63c45e1dc 100644
--- a/internal/schema/decoder.go
+++ b/internal/schema/decoder.go
@@ -74,19 +74,19 @@ func (d *Decoder) Decode(dst interface{}, src map[string][]string) error {
 	}
 	v = v.Elem()
 	t := v.Type()
-	errors := MultiError{}
+	multiError := MultiError{}
 	for path, values := range src {
 		if parts, err := d.cache.parsePath(path, t); err == nil {
 			if err = d.decode(v, path, parts, values); err != nil {
-				errors[path] = err
+				multiError[path] = err
 			}
 		} else if !d.ignoreUnknownKeys {
-			errors[path] = UnknownKeyError{Key: path}
+			multiError[path] = UnknownKeyError{Key: path}
 		}
 	}
-	errors.merge(d.checkRequired(t, src))
-	if len(errors) > 0 {
-		return errors
+	multiError.merge(d.checkRequired(t, src))
+	if len(multiError) > 0 {
+		return multiError
 	}
 	return nil
 }
diff --git a/middleware/cache/cache_test.go b/middleware/cache/cache_test.go
index 4c7e155a36..f991d24b0a 100644
--- a/middleware/cache/cache_test.go
+++ b/middleware/cache/cache_test.go
@@ -5,6 +5,7 @@ package cache
 import (
 	"bytes"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"math"
 	"net/http"
@@ -126,7 +127,10 @@ func Test_Cache_WithSeveralRequests(t *testing.T) {
 				rsp, err := app.Test(httptest.NewRequest(http.MethodGet, fmt.Sprintf("/%d", id), nil))
 				utils.AssertEqual(t, nil, err)
 
-				defer rsp.Body.Close()
+				defer func(Body io.ReadCloser) {
+					err := Body.Close()
+					utils.AssertEqual(t, nil, err)
+				}(rsp.Body)
 
 				idFromServ, err := ioutil.ReadAll(rsp.Body)
 				utils.AssertEqual(t, nil, err)
diff --git a/middleware/session/session_test.go b/middleware/session/session_test.go
index 4afef2458d..19bf121fa0 100644
--- a/middleware/session/session_test.go
+++ b/middleware/session/session_test.go
@@ -127,9 +127,9 @@ func Test_Session_Types(t *testing.T) {
 		Name: "John",
 	}
 	// set value
-	var vbool bool = true
-	var vstring string = "str"
-	var vint int = 13
+	var vbool = true
+	var vstring = "str"
+	var vint = 13
 	var vint8 int8 = 13
 	var vint16 int16 = 13
 	var vint32 int32 = 13