diff --git a/header_test.go b/header_test.go
index e0670e5..81bac6f 100644
--- a/header_test.go
+++ b/header_test.go
@@ -21,6 +21,16 @@ func TestRequestHeaderReadEOF(t *testing.T) {
 	if err != io.EOF {
 		t.Fatalf("unexpected error: %s. Expecting %s", err, io.EOF)
 	}
+
+	// incomplete request header mustn't return io.EOF
+	br = bufio.NewReader(bytes.NewBufferString("GET "))
+	err = r.Read(br)
+	if err == nil {
+		t.Fatalf("expecting error")
+	}
+	if err == io.EOF {
+		t.Fatalf("expecting non-EOF error")
+	}
 }
 
 func TestResponseHeaderReadEOF(t *testing.T) {
@@ -34,6 +44,16 @@ func TestResponseHeaderReadEOF(t *testing.T) {
 	if err != io.EOF {
 		t.Fatalf("unexpected error: %s. Expecting %s", err, io.EOF)
 	}
+
+	// incomplete response header mustn't return io.EOF
+	br = bufio.NewReader(bytes.NewBufferString("HTTP/1.1 "))
+	err = r.Read(br)
+	if err == nil {
+		t.Fatalf("expecting error")
+	}
+	if err == io.EOF {
+		t.Fatalf("expecting non-EOF error")
+	}
 }
 
 func TestResponseHeaderOldVersion(t *testing.T) {
diff --git a/http_test.go b/http_test.go
index 7fb4f07..423ffc9 100644
--- a/http_test.go
+++ b/http_test.go
@@ -22,6 +22,16 @@ func TestRequestReadEOF(t *testing.T) {
 	if err != io.EOF {
 		t.Fatalf("unexpected error: %s. Expecting %s", err, io.EOF)
 	}
+
+	// incomplete request mustn't return io.EOF
+	br = bufio.NewReader(bytes.NewBufferString("POST / HTTP/1.1\r\nContent-Type: aa\r\nContent-Length: 1234\r\n\r\nIncomplete body"))
+	err = r.Read(br)
+	if err == nil {
+		t.Fatalf("expecting error")
+	}
+	if err == io.EOF {
+		t.Fatalf("expecting non-EOF error")
+	}
 }
 
 func TestResponseReadEOF(t *testing.T) {
@@ -35,6 +45,16 @@ func TestResponseReadEOF(t *testing.T) {
 	if err != io.EOF {
 		t.Fatalf("unexpected error: %s. Expecting %s", err, io.EOF)
 	}
+
+	// incomplete response mustn't return io.EOF
+	br = bufio.NewReader(bytes.NewBufferString("HTTP/1.1 200 OK\r\nContent-Type: aaa\r\nContent-Length: 123\r\n\r\nIncomplete body"))
+	err = r.Read(br)
+	if err == nil {
+		t.Fatalf("expecting error")
+	}
+	if err == io.EOF {
+		t.Fatalf("expecting non-EOF error")
+	}
 }
 
 func TestResponseWriteTo(t *testing.T) {