Add Test_SaveFile (#318)

* ctx_test: impl Test_SaveFile

* fixup! ctx_test: impl Test_SaveFile

Author: TianhongWu

ctx_test.go

@@ -13,6 +13,7 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"net/url"
+	"os"
 	"strconv"
 	"strings"
 	"testing"
@@ -647,7 +648,56 @@ func Test_Route(t *testing.T) {
 	}
 }
 func Test_SaveFile(t *testing.T) {
-	// TODO
+	app := New()
+	app.Post("/test", func(c *Ctx) {
+		fh, err := c.FormFile("file")
+		if err != nil {
+			t.Fatalf(`%s: %s`, t.Name(), err)
+		}
+		tempFile, err := ioutil.TempFile(os.TempDir(), "test-")
+		if err != nil {
+			t.Fatalf(`%s: %s`, t.Name(), err)
+		}
+		defer os.Remove(tempFile.Name())
+		err = c.SaveFile(fh, tempFile.Name())
+		if err != nil {
+			t.Fatalf(`%s: %s`, t.Name(), err)
+		}
+		bs, err := ioutil.ReadFile(tempFile.Name())
+		if err != nil {
+			t.Fatalf(`%s: %s`, t.Name(), err)
+		}
+		expect := "hello world"
+		if string(bs) != expect {
+			t.Fatalf(`Expecting %s, got %s`, expect, string(bs))
+		}
+	})
+
+	body := &bytes.Buffer{}
+	writer := multipart.NewWriter(body)
+
+	ioWriter, err := writer.CreateFormFile("file", "test")
+	if err != nil {
+		t.Fatalf(`%s: %s`, t.Name(), err)
+	}
+
+	_, err = ioWriter.Write([]byte("hello world"))
+	if err != nil {
+		t.Fatalf(`%s: %s`, t.Name(), err)
+	}
+	writer.Close()
+
+	req, _ := http.NewRequest("POST", "/test", body)
+	req.Header.Set("Content-Type", writer.FormDataContentType())
+	req.Header.Set("Content-Length", strconv.Itoa(len(body.Bytes())))
+
+	resp, err := app.Test(req)
+	if err != nil {
+		t.Fatalf(`%s: %s`, t.Name(), err)
+	}
+	if resp.StatusCode != 200 {
+		t.Fatalf(`%s: StatusCode %v`, t.Name(), resp.StatusCode)
+	}
 }
 func Test_Secure(t *testing.T) {
 	app := New()