From 1af6e9044268a3d741d17bb9ec1984ae819b0b40 Mon Sep 17 00:00:00 2001
From: Frederic BIDON <fredbi@yahoo.com>
Date: Thu, 7 Dec 2023 17:00:55 +0100
Subject: [PATCH] added check to prevent HasContent() to panic after the reader
 is closed

* fixes #268

Signed-off-by: Frederic BIDON <fredbi@yahoo.com>
---
 request.go      |  7 +++++++
 request_test.go | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+)

diff --git a/request.go b/request.go
index 8c322af..3b9e983 100644
--- a/request.go
+++ b/request.go
@@ -16,6 +16,7 @@ package runtime
 
 import (
 	"bufio"
+	"errors"
 	"io"
 	"net/http"
 	"strings"
@@ -96,10 +97,16 @@ func (p *peekingReader) Read(d []byte) (int, error) {
 	if p == nil {
 		return 0, io.EOF
 	}
+	if p.underlying == nil {
+		return 0, io.ErrUnexpectedEOF
+	}
 	return p.underlying.Read(d)
 }
 
 func (p *peekingReader) Close() error {
+	if p.underlying == nil {
+		return errors.New("reader already closed")
+	}
 	p.underlying = nil
 	if p.orig != nil {
 		return p.orig.Close()
diff --git a/request_test.go b/request_test.go
index ac5bb55..4617591 100644
--- a/request_test.go
+++ b/request_test.go
@@ -137,6 +137,39 @@ func TestPeekingReader(t *testing.T) {
 	require.Equal(t, 1, cbr.peeks)
 	require.Equal(t, 2, cbr.reads)
 	require.Equal(t, 0, cbr.br.Buffered())
+
+	t.Run("closing a closed peekingReader", func(t *testing.T) {
+		const content = "content"
+		r := newPeekingReader(io.NopCloser(strings.NewReader(content)))
+		require.NoError(t, r.Close())
+
+		require.NotPanics(t, func() {
+			err := r.Close()
+			require.Error(t, err)
+		})
+	})
+
+	t.Run("reading from a closed peekingReader", func(t *testing.T) {
+		const content = "content"
+		r := newPeekingReader(io.NopCloser(strings.NewReader(content)))
+		require.NoError(t, r.Close())
+
+		require.NotPanics(t, func() {
+			_, err := io.ReadAll(r)
+			require.Error(t, err)
+			require.ErrorIs(t, err, io.ErrUnexpectedEOF)
+		})
+	})
+
+	t.Run("reading from a nil peekingReader", func(t *testing.T) {
+		var r *peekingReader
+		require.NotPanics(t, func() {
+			buf := make([]byte, 10)
+			_, err := r.Read(buf)
+			require.Error(t, err)
+			require.ErrorIs(t, err, io.EOF)
+		})
+	})
 }
 
 func TestJSONRequest(t *testing.T) {