diff --git a/context_test.go b/context_test.go
index 85e0a616..842a150b 100644
--- a/context_test.go
+++ b/context_test.go
@@ -33,9 +33,6 @@ import (
 var _ context.Context = (*Context)(nil)
 
 // Unit tests TODO
-// func (c *Context) File(filepath string) {
-// func (c *Context) Negotiate(code int, config Negotiate) {
-// BAD case: func (c *Context) Render(code int, render render.Render, obj ...interface{}) {
 // test that information is not leaked when reusing Contexts (using the Pool)
 
 func createMultipartRequest() *http.Request {
@@ -88,6 +85,31 @@ func TestContextFormFile(t *testing.T) {
 	assert.NoError(t, c.SaveUploadedFile(f, "test"))
 }
 
+func TestContextFormFileFailed(t *testing.T) {
+	buf := new(bytes.Buffer)
+	c, _ := CreateTestContext(httptest.NewRecorder())
+	c.Request, _ = http.NewRequest("POST", "/", buf)
+	_, err := c.FormFile("file")
+	if assert.Error(t, err) {
+		assert.Equal(t, http.ErrNotMultipart, err)
+	}
+
+	mw := multipart.NewWriter(buf)
+	w, err := mw.CreateFormFile("file", "test")
+	if assert.NoError(t, err) {
+		_, err = w.Write([]byte("test"))
+		assert.NoError(t, err)
+	}
+	mw.Close()
+
+	c.Request, _ = http.NewRequest("POST", "/", buf)
+	c.Request.Header.Set("Content-Type", mw.FormDataContentType())
+	_, err = c.FormFile("file2")
+	if assert.Error(t, err) {
+		assert.Equal(t, http.ErrMissingFile, err)
+	}
+}
+
 func TestContextMultipartForm(t *testing.T) {
 	buf := new(bytes.Buffer)
 	mw := multipart.NewWriter(buf)
@@ -142,6 +164,7 @@ func TestSaveUploadedCreateFailed(t *testing.T) {
 	}
 
 	assert.Error(t, c.SaveUploadedFile(f, "/"))
+	assert.Error(t, c.SaveUploadedFile(f, "/file/"))
 }
 
 func TestContextReset(t *testing.T) {
@@ -609,6 +632,13 @@ func TestContextPostFormMultipart(t *testing.T) {
 
 	dicts = c.PostFormMap("nokey")
 	assert.Equal(t, 0, len(dicts))
+
+	c.Request = createMultipartRequest()
+	c.formCache = nil
+	c.Request.Header = http.Header{"Content-Type": {`multipart/form-data; boundary="foo123"`}}
+	values, ok = c.GetPostFormArray("array")
+	assert.Nil(t, values)
+	assert.False(t, ok)
 }
 
 func TestContextSetCookie(t *testing.T) {
@@ -1113,7 +1143,6 @@ func TestContextHeaders(t *testing.T) {
 	assert.False(t, exist)
 }
 
-// TODO
 func TestContextRenderRedirectWithRelativePath(t *testing.T) {
 	w := httptest.NewRecorder()
 	c, _ := CreateTestContext(w)
diff --git a/debug_test.go b/debug_test.go
index abe8b41c..9ab2ed3c 100644
--- a/debug_test.go
+++ b/debug_test.go
@@ -19,10 +19,6 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-// TODO
-// func debugRoute(httpMethod, absolutePath string, handlers HandlersChain) {
-// func debugPrint(format string, values ...interface{}) {
-
 func TestIsDebugging(t *testing.T) {
 	SetMode(DebugMode)
 	assert.True(t, IsDebugging())
diff --git a/render/render_test.go b/render/render_test.go
index 3509db3c..edb2466b 100644
--- a/render/render_test.go
+++ b/render/render_test.go
@@ -19,9 +19,6 @@ import (
 	"google.golang.org/protobuf/proto"
 )
 
-// TODO unit tests
-// test errors
-
 func TestRenderJSON(t *testing.T) {
 	w := httptest.NewRecorder()
 	data := map[string]any{
@@ -105,6 +102,18 @@ func TestRenderSecureJSONFail(t *testing.T) {
 	// json: unsupported type: chan int
 	err := (SecureJSON{"while(1);", data}).Render(w)
 	assert.Error(t, err)
+
+	// test ResponseWriter.Write failed
+	ts := httptest.NewServer(http.HandlerFunc(
+		func(w http.ResponseWriter, r *http.Request) {
+			// Restrict the length of returned packages
+			w.Header().Set("Content-Length", "0")
+			datas := []map[string]any{{"foo": "bar"}, {"bar": "foo"}}
+			err2 := (SecureJSON{"while(1);", datas}).Render(w)
+			assert.Error(t, err2)
+		}))
+	defer ts.Close()
+	_, _ = http.Get(ts.URL)
 }
 
 func TestRenderJsonpJSON(t *testing.T) {
@@ -157,6 +166,19 @@ func TestRenderJsonpJSONFail(t *testing.T) {
 	// json: unsupported type: chan int
 	err := (JsonpJSON{"x", data}).Render(w)
 	assert.Error(t, err)
+
+	// test ResponseWriter.Write failed
+	for _, l := range []string{"0", "1", "2", "4"} {
+		ts := httptest.NewServer(http.HandlerFunc(
+			func(w http.ResponseWriter, r *http.Request) {
+				// Restrict the length of returned packages
+				w.Header().Set("Content-Length", l)
+				err2 := (JsonpJSON{"x", ""}).Render(w)
+				assert.Error(t, err2)
+			}))
+		defer ts.Close()
+		_, _ = http.Get(ts.URL)
+	}
 }
 
 func TestRenderAsciiJSON(t *testing.T) {
@@ -510,3 +532,27 @@ func TestRenderReaderNoContentLength(t *testing.T) {
 	assert.Equal(t, headers["Content-Disposition"], w.Header().Get("Content-Disposition"))
 	assert.Equal(t, headers["x-request-id"], w.Header().Get("x-request-id"))
 }
+
+func TestReaderTOML(t *testing.T) {
+	w := httptest.NewRecorder()
+	data := `
+	title = "TOML Example"
+	[server]
+	IP = "127.0.0.1"
+	Port = ":8080"
+	`
+	(TOML{data}).WriteContentType(w)
+	err := (TOML{data}).Render(w)
+
+	assert.NoError(t, err)
+	assert.Equal(t, "application/toml; charset=utf-8", w.Header().Get("Content-Type"))
+	assert.Equal(t, "\"\\n\\ttitle = \\\"TOML Example\\\"\\n\\t[server]\\n\\tIP = \\\"127.0.0.1\\\"\\n\\tPort = \\\":8080\\\"\\n\\t\"", w.Body.String())
+}
+
+func TestRenderTOMLFail(t *testing.T) {
+	w := httptest.NewRecorder()
+	data := make(chan int)
+
+	// TOML: unsupported type: chan int
+	assert.Error(t, (TOML{data}).Render(w))
+}
diff --git a/response_writer_test.go b/response_writer_test.go
index 57d163c9..209f5500 100644
--- a/response_writer_test.go
+++ b/response_writer_test.go
@@ -12,11 +12,6 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-// TODO
-// func (w *responseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
-// func (w *responseWriter) CloseNotify() <-chan bool {
-// func (w *responseWriter) Flush() {
-
 var (
 	_ ResponseWriter      = &responseWriter{}
 	_ http.ResponseWriter = &responseWriter{}