use the os.ErrDeadlineExceeded for stream deadline errors on Go 1.15

stream_deadline_error_test.go

@@ -0,0 +1,21 @@
+// +build go1.15
+
+package quic
+
+import (
+	"errors"
+	"os"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Deadline Error", func() {
+	It("is a net.Error that wraps os.ErrDeadlineError", func() {
+		err := deadlineError{}
+		Expect(err.Temporary()).To(BeTrue())
+		Expect(err.Timeout()).To(BeTrue())
+		Expect(errors.Is(err, os.ErrDeadlineExceeded)).To(BeTrue())
+		Expect(errors.Unwrap(err)).To(Equal(os.ErrDeadlineExceeded))
+	})
+})