fix(test/stdio): address io:read/write on closed pipe error (#360)

Author: cryo-zd

server/stdio.go

@@ -244,6 +244,11 @@ func (s *StdioServer) processMessage(
 	line string,
 	writer io.Writer,
 ) error {
+	// If line is empty, likely due to ctx cancellation
+	if len(line) == 0 {
+		return nil
+	}
+
 	// Parse the message as raw JSON
 	var rawMessage json.RawMessage
 	if err := json.Unmarshal([]byte(line), &rawMessage); err != nil {

server/stdio_test.go

@@ -50,6 +50,7 @@ func TestStdioServer(t *testing.T) {
 			if err != nil && err != io.EOF && err != context.Canceled {
 				serverErrCh <- err
 			}
+			stdoutWriter.Close()
 			close(serverErrCh)
 		}()
 
@@ -106,7 +107,6 @@ func TestStdioServer(t *testing.T) {
 		// Clean up
 		cancel()
 		stdinWriter.Close()
-		stdoutWriter.Close()
 
 		// Check for server errors
 		if err := <-serverErrCh; err != nil {
@@ -162,6 +162,7 @@ func TestStdioServer(t *testing.T) {
 			if err != nil && err != io.EOF && err != context.Canceled {
 				serverErrCh <- err
 			}
+			stdoutWriter.Close()
 			close(serverErrCh)
 		}()
 
@@ -260,7 +261,6 @@ func TestStdioServer(t *testing.T) {
 		// Clean up
 		cancel()
 		stdinWriter.Close()
-		stdoutWriter.Close()
 
 		// Check for server errors
 		if err := <-serverErrCh; err != nil {