👷 add ctx.Render test cases

.github/TEST_DATA/template-invalid.html

@@ -0,0 +1 @@
+<h1>{{.Title}</h1>

ctx.go

@@ -15,7 +15,6 @@ import (
 	"log"
 	"mime/multipart"
 	"net/http"
-	"os"
 	"path/filepath"
 	"strconv"
 	"strings"
@@ -791,15 +790,7 @@ func (ctx *Ctx) Render(name string, bind interface{}, layouts ...string) (err er
 	} else {
 		// Render raw template using 'name' as filepath if no engine is set
 		var tmpl *template.Template
-		// Read file
-		f, err := os.Open(filepath.Clean(name))
-		if err != nil {
-			return err
-		}
-		if _, err = buf.ReadFrom(f); err != nil {
-			return err
-		}
-		if err = f.Close(); err != nil {
+		if _, err = readContent(buf, name); err != nil {
 			return err
 		}
 		// Parse template

ctx_test.go

@@ -10,6 +10,7 @@ package fiber
 import (
 	"bufio"
 	"bytes"
+	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -1500,7 +1501,10 @@ func Test_Ctx_Render(t *testing.T) {
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "<h1>Hello, World!</h1>", string(ctx.Fasthttp.Response.Body()))
 
-	err = ctx.Render("./.github/TEST_DATA/invalid.html", nil)
+	err = ctx.Render("./.github/TEST_DATA/template-non-exists.html", nil)
+	utils.AssertEqual(t, false, err == nil)
+
+	err = ctx.Render("./.github/TEST_DATA/template-invalid.html", nil)
 	utils.AssertEqual(t, false, err == nil)
 }
 
@@ -1533,6 +1537,7 @@ func Test_Ctx_Render_Engine(t *testing.T) {
 	utils.AssertEqual(t, "<h1>Hello, World!</h1>", string(ctx.Fasthttp.Response.Body()))
 }
 
+// go test -v -run=^$ -bench=Benchmark_Ctx_Render_Engine -benchmem -count=4
 func Benchmark_Ctx_Render_Engine(b *testing.B) {
 	engine := &testTemplateEngine{}
 	err := engine.Load()
@@ -1552,19 +1557,43 @@ func Benchmark_Ctx_Render_Engine(b *testing.B) {
 	utils.AssertEqual(b, "<h1>Hello, World!</h1>", string(ctx.Fasthttp.Response.Body()))
 }
 
+type errorTemplateEngine struct{}
+
+func (t errorTemplateEngine) Render(w io.Writer, name string, bind interface{}, layout ...string) error {
+	return errors.New("errorTemplateEngine")
+}
+
+func (t errorTemplateEngine) Load() error { return nil }
+
+// go test -run Test_Ctx_Render_Engine_Error
+func Test_Ctx_Render_Engine_Error(t *testing.T) {
+	app := New()
+	app.Settings.Views = errorTemplateEngine{}
+	ctx := app.AcquireCtx(&fasthttp.RequestCtx{})
+	defer app.ReleaseCtx(ctx)
+	err := ctx.Render("index.tmpl", nil)
+	utils.AssertEqual(t, false, err == nil)
+}
+
 // go test -run Test_Ctx_Render_Go_Template
 func Test_Ctx_Render_Go_Template(t *testing.T) {
 	t.Parallel()
+
 	file, err := ioutil.TempFile(os.TempDir(), "fiber")
 	utils.AssertEqual(t, nil, err)
 	defer os.Remove(file.Name())
+
 	_, err = file.Write([]byte("template"))
 	utils.AssertEqual(t, nil, err)
+
 	err = file.Close()
 	utils.AssertEqual(t, nil, err)
+
 	app := New()
+
 	ctx := app.AcquireCtx(&fasthttp.RequestCtx{})
 	defer app.ReleaseCtx(ctx)
+
 	err = ctx.Render(file.Name(), nil)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "template", string(ctx.Fasthttp.Response.Body()))

utils.go

@@ -8,7 +8,10 @@ import (
 	"bytes"
 	"fmt"
 	"hash/crc32"
+	"io"
 	"net"
+	"os"
+	"path/filepath"
 	"strings"
 	"time"
 
@@ -17,6 +20,17 @@ import (
 	fasthttp "github.com/valyala/fasthttp"
 )
 
+// readContent opens a named file and read content from it
+func readContent(rf io.ReaderFrom, name string) (int64, error) {
+	// Read file
+	f, err := os.Open(filepath.Clean(name))
+	if err != nil {
+		return 0, err
+	}
+	defer f.Close()
+	return rf.ReadFrom(f)
+}
+
 // quoteString escape special characters in a given string
 func quoteString(raw string) string {
 	bb := bytebufferpool.Get()