move all error things to new qerr package, replacing errorcodes

qerr/error_codes.go

@@ -0,0 +1,12 @@
+package qerr
+
+// The error codes defined by QUIC
+// Remeber to run `go generate ./...` whenever the error codes change.
+//go:generate stringer -type=ErrorCode
+const (
+	InternalError      ErrorCode = 1
+	InvalidFrameData   ErrorCode = 4
+	DecryptionFailure  ErrorCode = 12
+	PeerGoingAway      ErrorCode = 16
+	NetworkIdleTimeout ErrorCode = 25
+)

qerr/errorcode_string.go

@@ -0,0 +1,38 @@
+// Code generated by "stringer -type=ErrorCode"; DO NOT EDIT
+
+package qerr
+
+import "fmt"
+
+const (
+	_ErrorCode_name_0 = "InternalError"
+	_ErrorCode_name_1 = "InvalidFrameData"
+	_ErrorCode_name_2 = "DecryptionFailure"
+	_ErrorCode_name_3 = "PeerGoingAway"
+	_ErrorCode_name_4 = "NetworkIdleTimeout"
+)
+
+var (
+	_ErrorCode_index_0 = [...]uint8{0, 13}
+	_ErrorCode_index_1 = [...]uint8{0, 16}
+	_ErrorCode_index_2 = [...]uint8{0, 17}
+	_ErrorCode_index_3 = [...]uint8{0, 13}
+	_ErrorCode_index_4 = [...]uint8{0, 18}
+)
+
+func (i ErrorCode) String() string {
+	switch {
+	case i == 1:
+		return _ErrorCode_name_0
+	case i == 4:
+		return _ErrorCode_name_1
+	case i == 12:
+		return _ErrorCode_name_2
+	case i == 16:
+		return _ErrorCode_name_3
+	case i == 25:
+		return _ErrorCode_name_4
+	default:
+		return fmt.Sprintf("ErrorCode(%d)", i)
+	}
+}

qerr/errorcodes_test.go

@@ -0,0 +1,34 @@
+package qerr_test
+
+import (
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"os"
+	"strconv"
+
+	"github.com/lucas-clemente/quic-go/qerr"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("error codes", func() {
+	// If this test breaks, you should run `go generate ./...`
+	It("has a string representation for every error code", func() {
+		// We parse the error code file, extract all constants, and verify that
+		// each of them has a string version. Go FTW!
+		filename := os.Getenv("GOPATH") + "/src/github.com/lucas-clemente/quic-go/qerr/error_codes.go"
+		fileAst, err := parser.ParseFile(token.NewFileSet(), filename, nil, 0)
+		Expect(err).NotTo(HaveOccurred())
+		constSpecs := fileAst.Decls[0].(*ast.GenDecl).Specs
+		Expect(len(constSpecs)).To(BeNumerically(">", 4)) // at time of writing
+		for _, c := range constSpecs {
+			name := c.(*ast.ValueSpec).Names[0].Name
+			valString := c.(*ast.ValueSpec).Values[0].(*ast.BasicLit).Value
+			val, err := strconv.Atoi(valString)
+			Expect(err).NotTo(HaveOccurred())
+			Expect(qerr.ErrorCode(val).String()).To(Equal(name))
+		}
+	})
+})

qerr/errors_suite_test.go

@@ -0,0 +1,13 @@
+package qerr_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+func TestErrorcodes(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Errors Suite")
+}

qerr/quic_error.go

@@ -0,0 +1,30 @@
+package qerr
+
+import (
+	"fmt"
+)
+
+// ErrorCode can be used as a normal error without reason.
+type ErrorCode uint32
+
+func (e ErrorCode) Error() string {
+	return e.String()
+}
+
+// A QuicError consists of an error code plus a error reason
+type QuicError struct {
+	ErrorCode    ErrorCode
+	ErrorMessage string
+}
+
+// Error creates a new QuicError instance
+func Error(errorCode ErrorCode, errorMessage string) *QuicError {
+	return &QuicError{
+		ErrorCode:    errorCode,
+		ErrorMessage: errorMessage,
+	}
+}
+
+func (e *QuicError) Error() string {
+	return fmt.Sprintf("%s: %s", e.ErrorCode.String(), e.ErrorMessage)
+}

qerr/quic_error_test.go

@@ -0,0 +1,15 @@
+package qerr_test
+
+import (
+	"github.com/lucas-clemente/quic-go/qerr"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Quic error", func() {
+	It("has a string representation", func() {
+		err := qerr.Error(qerr.InternalError, "foobar")
+		Expect(err.Error()).To(Equal("InternalError: foobar"))
+	})
+})