feat: ability to edit status messages

header.go

@@ -33,6 +33,7 @@ type ResponseHeader struct {
 	noDefaultDate        bool
 
 	statusCode            int
+	statusLine            []byte
 	contentLength         int
 	contentLengthBytes    []byte
 	secureErrorLogMessage bool
@@ -136,6 +137,11 @@ func (h *ResponseHeader) SetStatusCode(statusCode int) {
 	h.statusCode = statusCode
 }
 
+// SetStatusLine sets response status line bytes.
+func (h *ResponseHeader) SetStatusLine(statusLine []byte) {
+	h.statusLine = statusLine
+}
+
 // SetLastModified sets 'Last-Modified' header to the given value.
 func (h *ResponseHeader) SetLastModified(t time.Time) {
 	h.bufKV.value = AppendHTTPDate(h.bufKV.value[:0], t)
@@ -1639,7 +1645,12 @@ func (h *ResponseHeader) AppendBytes(dst []byte) []byte {
 	if statusCode < 0 {
 		statusCode = StatusOK
 	}
-	dst = append(dst, statusLine(statusCode)...)
+
+	if h.statusLine != nil {
+		dst = append(dst, h.statusLine...)
+	} else {
+		dst = append(dst, statusLine(statusCode)...)
+	}
 
 	server := h.Server()
 	if len(server) != 0 {

http_test.go

@@ -837,6 +837,24 @@ func TestResponseSkipBody(t *testing.T) {
 		t.Fatalf("unexpected content-type in response %q", s)
 	}
 
+	// set StatusNoContent with statusLine
+	r.Header.SetStatusCode(StatusNoContent)
+	r.Header.SetStatusLine([]byte("HTTP/1.1 204 NC\r\n"))
+	r.SetBodyString("foobar")
+	s = r.String()
+	if strings.Contains(s, "\r\n\r\nfoobar") {
+		t.Fatalf("unexpected non-zero body in response %q", s)
+	}
+	if strings.Contains(s, "Content-Length: ") {
+		t.Fatalf("unexpected content-length in response %q", s)
+	}
+	if strings.Contains(s, "Content-Type: ") {
+		t.Fatalf("unexpected content-type in response %q", s)
+	}
+	if !strings.HasPrefix(s, "HTTP/1.1 204 NC\r\n") {
+		t.Fatalf("expecting non-default status line in response %q", s)
+	}
+
 	// explicitly skip body
 	r.Header.SetStatusCode(StatusOK)
 	r.SkipBody = true