tools/fidl/gidl/dart/conformance.go - fuchsia - Git at Google

 // Copyright 2018 The Fuchsia Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 package dart

 import (
 	"bytes"
 	"fmt"
 	"strings"
 	"text/template"

 	gidlconfig "go.fuchsia.dev/fuchsia/tools/fidl/gidl/config"
 	gidlir "go.fuchsia.dev/fuchsia/tools/fidl/gidl/ir"
 	gidlmixer "go.fuchsia.dev/fuchsia/tools/fidl/gidl/mixer"
 	fidl "go.fuchsia.dev/fuchsia/tools/fidl/lib/fidlgen"
 )

 var tmpl = template.Must(template.New("tmpls").Parse(`
 // @dart = 2.8

 // Ignore unused imports so that GIDL tests can be commented out without error.
 // ignore_for_file: unused_import

 import 'dart:typed_data';

 import 'package:test/test.dart';
 import 'package:fidl/fidl.dart' as fidl;
 import 'package:topaz.lib.gidl/gidl.dart';
 import 'package:topaz.lib.gidl/handles.dart';
 import 'package:zircon/zircon.dart';

 import 'package:fidl_conformance/fidl_async.dart';

 void main() {
 	group('conformance', () {
 		group('encode success cases', () {
 			{{ range .EncodeSuccessCases }}
 			{{- if .HandleDefs }}
 			EncodeSuccessCase.runWithHandles(
 				{{ .EncoderName }},
 				{{ .Name }},
 				(List<Handle> handleDefs) => {{ .Value }},
 				{{ .ValueType }},
 				{{ .Bytes }},
 				{{ .HandleDefs }},
 				{{ .Handles }});
 			{{- else }}
 			EncodeSuccessCase.run(
 				{{ .EncoderName }},
 				{{ .Name }},
 				{{ .Value }},
 				{{ .ValueType }},
 				{{ .Bytes }});
             {{- end }}
 			{{ end }}
 				});

 		group('decode success cases', () {
 			{{ range .DecodeSuccessCases }}
 			{{- if .HandleDefs }}
 			DecodeSuccessCase.runWithHandles(
 				{{ .DecoderName }},
 				{{ .Name }},
 				(List<Handle> handleDefs) => {{ .Value }},
 				{{ .ValueType }},
 				{{ .Bytes }},
 				{{ .HandleDefs }},
 				{{ .Handles }},
 				{{ .UnusedHandles }});
 			{{- else }}
 			DecodeSuccessCase.run(
 				{{ .DecoderName }},
 				{{ .Name }},
 				{{ .Value }},
 				{{ .ValueType }},
 				{{ .Bytes }});
             {{- end }}
 			{{ end }}
 				});

 		group('encode failure cases', () {
 			{{ range .EncodeFailureCases }}
 			{{- if .HandleDefs }}
 			EncodeFailureCase.runWithHandles(
 				{{ .EncoderName }},
 				{{ .Name }},
 				(List<Handle> handleDefs) => {{ .Value }},
 				{{ .ValueType }},
 				{{ .ErrorCode }},
 				{{ .HandleDefs }});
 			{{- else }}
 			EncodeFailureCase.run(
 				{{ .EncoderName }},
 				{{ .Name }},
 				() => {{ .Value }},
 				{{ .ValueType }},
 				{{ .ErrorCode }});
 			{{- end }}
 			{{ end }}
 				});

 		group('decode failure cases', () {
 			{{ range .DecodeFailureCases }}
 			DecodeFailureCase.run(
 				{{ .DecoderName }},
 				{{ .Name }},
 				{{ .ValueType }},
 				{{ .Bytes }},
 			{{- if .HandleDefs }}
 				{{ .ErrorCode }},
 				{{ .HandleDefs }},
 				{{ .Handles }});
 			{{- else }}
 				{{ .ErrorCode }});
 			{{- end }}
 			{{ end }}
 				});
 	});
 }
 `))

 type tmplInput struct {
 	EncodeSuccessCases []encodeSuccessCase
 	DecodeSuccessCases []decodeSuccessCase
 	EncodeFailureCases []encodeFailureCase
 	DecodeFailureCases []decodeFailureCase
 }

 type encodeSuccessCase struct {
 	EncoderName, Name, Value, ValueType, Bytes, HandleDefs, Handles string
 }

 type decodeSuccessCase struct {
 	DecoderName, Name, Value, ValueType, Bytes, HandleDefs, Handles, UnusedHandles string
 }

 type encodeFailureCase struct {
 	EncoderName, Name, Value, ValueType, ErrorCode, HandleDefs string
 }

 type decodeFailureCase struct {
 	DecoderName, Name, ValueType, Bytes, ErrorCode, HandleDefs, Handles string
 }

 // Generate generates dart tests.
 func GenerateConformanceTests(gidl gidlir.All, fidl fidl.Root, config gidlconfig.GeneratorConfig) ([]byte, error) {
 	schema := gidlmixer.BuildSchema(fidl)
 	encodeSuccessCases, err := encodeSuccessCases(gidl.EncodeSuccess, schema)
 	if err != nil {
 		return nil, err
 	}
 	decodeSuccessCases, err := decodeSuccessCases(gidl.DecodeSuccess, schema)
 	if err != nil {
 		return nil, err
 	}
 	encodeFailureCases, err := encodeFailureCases(gidl.EncodeFailure, schema)
 	if err != nil {
 		return nil, err
 	}
 	decodeFailureCases, err := decodeFailureCases(gidl.DecodeFailure, schema)
 	if err != nil {
 		return nil, err
 	}
 	var buf bytes.Buffer
 	err = tmpl.Execute(&buf, tmplInput{
 		EncodeSuccessCases: encodeSuccessCases,
 		DecodeSuccessCases: decodeSuccessCases,
 		EncodeFailureCases: encodeFailureCases,
 		DecodeFailureCases: decodeFailureCases,
 	})
 	return buf.Bytes(), err
 }

 func encodeSuccessCases(gidlEncodeSuccesses []gidlir.EncodeSuccess, schema gidlmixer.Schema) ([]encodeSuccessCase, error) {
 	var encodeSuccessCases []encodeSuccessCase
 	for _, encodeSuccess := range gidlEncodeSuccesses {
 		decl, err := schema.ExtractDeclaration(encodeSuccess.Value, encodeSuccess.HandleDefs)
 		if err != nil {
 			return nil, fmt.Errorf("encode success %s: %s", encodeSuccess.Name, err)
 		}
 		valueStr := visit(encodeSuccess.Value, decl)
 		valueType := typeName(decl)
 		for _, encoding := range encodeSuccess.Encodings {
 			if !wireFormatSupported(encoding.WireFormat) {
 				continue
 			}
 			encodeSuccessCases = append(encodeSuccessCases, encodeSuccessCase{
 				EncoderName: encoderName(encoding.WireFormat),
 				Name:        testCaseName(encodeSuccess.Name, encoding.WireFormat),
 				Value:       valueStr,
 				ValueType:   valueType,
 				Bytes:       buildBytes(encoding.Bytes),
 				HandleDefs:  buildHandleDefs(encodeSuccess.HandleDefs),
 				Handles:     toDartIntList(encoding.Handles),
 			})
 		}
 	}
 	return encodeSuccessCases, nil
 }

 func decodeSuccessCases(gidlDecodeSuccesses []gidlir.DecodeSuccess, schema gidlmixer.Schema) ([]decodeSuccessCase, error) {
 	var decodeSuccessCases []decodeSuccessCase
 	for _, decodeSuccess := range gidlDecodeSuccesses {
 		decl, err := schema.ExtractDeclaration(decodeSuccess.Value, decodeSuccess.HandleDefs)
 		if err != nil {
 			return nil, fmt.Errorf("decode success %s: %s", decodeSuccess.Name, err)
 		}
 		valueStr := visit(decodeSuccess.Value, decl)
 		valueType := typeName(decl)
 		for _, encoding := range decodeSuccess.Encodings {
 			if !wireFormatSupported(encoding.WireFormat) {
 				continue
 			}
 			decodeSuccessCases = append(decodeSuccessCases, decodeSuccessCase{
 				DecoderName:   decoderName(encoding.WireFormat),
 				Name:          testCaseName(decodeSuccess.Name, encoding.WireFormat),
 				Value:         valueStr,
 				ValueType:     valueType,
 				Bytes:         buildBytes(encoding.Bytes),
 				HandleDefs:    buildHandleDefs(decodeSuccess.HandleDefs),
 				Handles:       toDartIntList(encoding.Handles),
 				UnusedHandles: toDartIntList(gidlir.GetUnusedHandles(decodeSuccess.Value, encoding.Handles)),
 			})
 		}
 	}
 	return decodeSuccessCases, nil
 }

 func encodeFailureCases(gidlEncodeFailures []gidlir.EncodeFailure, schema gidlmixer.Schema) ([]encodeFailureCase, error) {
 	var encodeFailureCases []encodeFailureCase
 	for _, encodeFailure := range gidlEncodeFailures {
 		decl, err := schema.ExtractDeclarationUnsafe(encodeFailure.Value)
 		if err != nil {
 			return nil, fmt.Errorf("encode failure %s: %s", encodeFailure.Name, err)
 		}
 		if gidlir.ContainsUnknownField(encodeFailure.Value) {
 			continue
 		}
 		errorCode, err := dartErrorCode(encodeFailure.Err)
 		if err != nil {
 			return nil, fmt.Errorf("encode failure %s: %s", encodeFailure.Name, err)
 		}
 		valueStr := visit(encodeFailure.Value, decl)
 		valueType := typeName(decl)
 		for _, wireFormat := range encodeFailure.WireFormats {
 			if !wireFormatSupported(wireFormat) {
 				continue
 			}
 			encodeFailureCases = append(encodeFailureCases, encodeFailureCase{
 				EncoderName: encoderName(wireFormat),
 				Name:        testCaseName(encodeFailure.Name, wireFormat),
 				Value:       valueStr,
 				ValueType:   valueType,
 				ErrorCode:   errorCode,
 				HandleDefs:  buildHandleDefs(encodeFailure.HandleDefs),
 			})
 		}
 	}
 	return encodeFailureCases, nil
 }

 func decodeFailureCases(gidlDecodeFailures []gidlir.DecodeFailure, schema gidlmixer.Schema) ([]decodeFailureCase, error) {
 	var decodeFailureCases []decodeFailureCase
 	for _, decodeFailure := range gidlDecodeFailures {
 		_, err := schema.ExtractDeclarationByName(decodeFailure.Type)
 		if err != nil {
 			return nil, fmt.Errorf("decode failure %s: %s", decodeFailure.Name, err)
 		}
 		errorCode, err := dartErrorCode(decodeFailure.Err)
 		if err != nil {
 			return nil, fmt.Errorf("decode failure %s: %s", decodeFailure.Name, err)
 		}
 		valueType := dartTypeName(decodeFailure.Type)
 		for _, encoding := range decodeFailure.Encodings {
 			if !wireFormatSupported(encoding.WireFormat) {
 				continue
 			}
 			decodeFailureCases = append(decodeFailureCases, decodeFailureCase{
 				DecoderName: decoderName(encoding.WireFormat),
 				Name:        testCaseName(decodeFailure.Name, encoding.WireFormat),
 				ValueType:   valueType,
 				Bytes:       buildBytes(encoding.Bytes),
 				ErrorCode:   errorCode,
 				HandleDefs:  buildHandleDefs(decodeFailure.HandleDefs),
 				Handles:     toDartIntList(encoding.Handles),
 			})
 		}
 	}
 	return decodeFailureCases, nil
 }

 func wireFormatSupported(wireFormat gidlir.WireFormat) bool {
 	return wireFormat == gidlir.V1WireFormat
 }

 func testCaseName(baseName string, wireFormat gidlir.WireFormat) string {
 	return fidl.SingleQuote(fmt.Sprintf("%s_%s", baseName, wireFormat))
 }

 func encoderName(wireFormat gidlir.WireFormat) string {
 	return fmt.Sprintf("Encoders.%s", wireFormat)
 }

 func decoderName(wireFormat gidlir.WireFormat) string {
 	return fmt.Sprintf("Decoders.%s", wireFormat)
 }

 func dartTypeName(inputType string) string {
 	return fmt.Sprintf("k%s_Type", inputType)
 }

 func buildBytes(bytes []byte) string {
 	var builder strings.Builder
 	builder.WriteString("Uint8List.fromList([\n")
 	for i, b := range bytes {
 		builder.WriteString(fmt.Sprintf("0x%02x,", b))
 		if i%8 == 7 {
 			// Note: empty comments are written to preserve formatting. See:
 			// https://github.com/dart-lang/dart_style/wiki/FAQ#why-does-the-formatter-mess-up-my-collection-literals
 			builder.WriteString(" //\n")
 		}
 	}
 	builder.WriteString("])")
 	return builder.String()
 }

 func toDartStr(value string) string {
 	var buf bytes.Buffer
 	buf.WriteRune('\'')
 	for _, r := range value {
 		if 0x20 <= r && r <= 0x7e { // printable ASCII rune
 			buf.WriteRune(r)
 		} else {
 			buf.WriteString(fmt.Sprintf(`\u{%x}`, r))
 		}
 	}
 	buf.WriteRune('\'')
 	return buf.String()
 }

 func toDartIntList(handles []gidlir.Handle) string {
 	var builder strings.Builder
 	builder.WriteString("[\n")
 	for i, handle := range handles {
 		builder.WriteString(fmt.Sprintf("%d,", handle))
 		if i%8 == 7 {
 			// Note: empty comments are written to preserve formatting. See:
 			// https://github.com/dart-lang/dart_style/wiki/FAQ#why-does-the-formatter-mess-up-my-collection-literals
 			builder.WriteString(" //\n")
 		}
 	}
 	builder.WriteString("]")
 	return builder.String()
 }

 // Dart error codes defined in: topaz/public/dart/fidl/lib/src/error.dart.
 var dartErrorCodeNames = map[gidlir.ErrorCode]string{
 	gidlir.StringTooLong:              "fidlStringTooLong",
 	gidlir.StringNotUtf8:              "unknown",
 	gidlir.NonEmptyStringWithNullBody: "fidlNonEmptyStringWithNullBody",
 	gidlir.StrictUnionFieldNotSet:     "fidlStrictXUnionFieldNotSet",
 	gidlir.StrictUnionUnknownField:    "fidlStrictXUnionUnknownField",
 	gidlir.StrictBitsUnknownBit:       "fidlInvalidBit",
 	gidlir.StrictEnumUnknownValue:     "fidlInvalidEnumValue",
 	gidlir.InvalidPaddingByte:         "unknown",
 	gidlir.TooFewHandles:              "fidlTooFewHandles",
 	gidlir.NonResourceUnknownHandles:  "fidlNonResourceHandle",
 }

 func dartErrorCode(code gidlir.ErrorCode) (string, error) {
 	if str, ok := dartErrorCodeNames[code]; ok {
 		return fmt.Sprintf("fidl.FidlErrorCode.%s", str), nil
 	}
 	return "", fmt.Errorf("no dart error string defined for error code %s", code)
 }
	// Copyright 2018 The Fuchsia Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	package dart

	import (
	"bytes"
	"fmt"
	"strings"
	"text/template"

	gidlconfig "go.fuchsia.dev/fuchsia/tools/fidl/gidl/config"
	gidlir "go.fuchsia.dev/fuchsia/tools/fidl/gidl/ir"
	gidlmixer "go.fuchsia.dev/fuchsia/tools/fidl/gidl/mixer"
	fidl "go.fuchsia.dev/fuchsia/tools/fidl/lib/fidlgen"
	)

	var tmpl = template.Must(template.New("tmpls").Parse(`
	// @dart = 2.8

	// Ignore unused imports so that GIDL tests can be commented out without error.
	// ignore_for_file: unused_import

	import 'dart:typed_data';

	import 'package:test/test.dart';
	import 'package:fidl/fidl.dart' as fidl;
	import 'package:topaz.lib.gidl/gidl.dart';
	import 'package:topaz.lib.gidl/handles.dart';
	import 'package:zircon/zircon.dart';

	import 'package:fidl_conformance/fidl_async.dart';

	void main() {
	group('conformance', () {
	group('encode success cases', () {
	{{ range .EncodeSuccessCases }}
	{{- if .HandleDefs }}
	EncodeSuccessCase.runWithHandles(
	{{ .EncoderName }},
	{{ .Name }},
	(List<Handle> handleDefs) => {{ .Value }},
	{{ .ValueType }},
	{{ .Bytes }},
	{{ .HandleDefs }},
	{{ .Handles }});
	{{- else }}
	EncodeSuccessCase.run(
	{{ .EncoderName }},
	{{ .Name }},
	{{ .Value }},
	{{ .ValueType }},
	{{ .Bytes }});
	{{- end }}
	{{ end }}
	});

	group('decode success cases', () {
	{{ range .DecodeSuccessCases }}
	{{- if .HandleDefs }}
	DecodeSuccessCase.runWithHandles(
	{{ .DecoderName }},
	{{ .Name }},
	(List<Handle> handleDefs) => {{ .Value }},
	{{ .ValueType }},
	{{ .Bytes }},
	{{ .HandleDefs }},
	{{ .Handles }},
	{{ .UnusedHandles }});
	{{- else }}
	DecodeSuccessCase.run(
	{{ .DecoderName }},
	{{ .Name }},
	{{ .Value }},
	{{ .ValueType }},
	{{ .Bytes }});
	{{- end }}
	{{ end }}
	});

	group('encode failure cases', () {
	{{ range .EncodeFailureCases }}
	{{- if .HandleDefs }}
	EncodeFailureCase.runWithHandles(
	{{ .EncoderName }},
	{{ .Name }},
	(List<Handle> handleDefs) => {{ .Value }},
	{{ .ValueType }},
	{{ .ErrorCode }},
	{{ .HandleDefs }});
	{{- else }}
	EncodeFailureCase.run(
	{{ .EncoderName }},
	{{ .Name }},
	() => {{ .Value }},
	{{ .ValueType }},
	{{ .ErrorCode }});
	{{- end }}
	{{ end }}
	});

	group('decode failure cases', () {
	{{ range .DecodeFailureCases }}
	DecodeFailureCase.run(
	{{ .DecoderName }},
	{{ .Name }},
	{{ .ValueType }},
	{{ .Bytes }},
	{{- if .HandleDefs }}
	{{ .ErrorCode }},
	{{ .HandleDefs }},
	{{ .Handles }});
	{{- else }}
	{{ .ErrorCode }});
	{{- end }}
	{{ end }}
	});
	});
	}
	`))

	type tmplInput struct {
	EncodeSuccessCases []encodeSuccessCase
	DecodeSuccessCases []decodeSuccessCase
	EncodeFailureCases []encodeFailureCase
	DecodeFailureCases []decodeFailureCase
	}

	type encodeSuccessCase struct {
	EncoderName, Name, Value, ValueType, Bytes, HandleDefs, Handles string
	}

	type decodeSuccessCase struct {
	DecoderName, Name, Value, ValueType, Bytes, HandleDefs, Handles, UnusedHandles string
	}

	type encodeFailureCase struct {
	EncoderName, Name, Value, ValueType, ErrorCode, HandleDefs string
	}

	type decodeFailureCase struct {
	DecoderName, Name, ValueType, Bytes, ErrorCode, HandleDefs, Handles string
	}

	// Generate generates dart tests.
	func GenerateConformanceTests(gidl gidlir.All, fidl fidl.Root, config gidlconfig.GeneratorConfig) ([]byte, error) {
	schema := gidlmixer.BuildSchema(fidl)
	encodeSuccessCases, err := encodeSuccessCases(gidl.EncodeSuccess, schema)
	if err != nil {
	return nil, err
	}
	decodeSuccessCases, err := decodeSuccessCases(gidl.DecodeSuccess, schema)
	if err != nil {
	return nil, err
	}
	encodeFailureCases, err := encodeFailureCases(gidl.EncodeFailure, schema)
	if err != nil {
	return nil, err
	}
	decodeFailureCases, err := decodeFailureCases(gidl.DecodeFailure, schema)
	if err != nil {
	return nil, err
	}
	var buf bytes.Buffer
	err = tmpl.Execute(&buf, tmplInput{
	EncodeSuccessCases: encodeSuccessCases,
	DecodeSuccessCases: decodeSuccessCases,
	EncodeFailureCases: encodeFailureCases,
	DecodeFailureCases: decodeFailureCases,
	})
	return buf.Bytes(), err
	}

	func encodeSuccessCases(gidlEncodeSuccesses []gidlir.EncodeSuccess, schema gidlmixer.Schema) ([]encodeSuccessCase, error) {
	var encodeSuccessCases []encodeSuccessCase
	for _, encodeSuccess := range gidlEncodeSuccesses {
	decl, err := schema.ExtractDeclaration(encodeSuccess.Value, encodeSuccess.HandleDefs)
	if err != nil {
	return nil, fmt.Errorf("encode success %s: %s", encodeSuccess.Name, err)
	}
	valueStr := visit(encodeSuccess.Value, decl)
	valueType := typeName(decl)
	for _, encoding := range encodeSuccess.Encodings {
	if !wireFormatSupported(encoding.WireFormat) {
	continue
	}
	encodeSuccessCases = append(encodeSuccessCases, encodeSuccessCase{
	EncoderName: encoderName(encoding.WireFormat),
	Name: testCaseName(encodeSuccess.Name, encoding.WireFormat),
	Value: valueStr,
	ValueType: valueType,
	Bytes: buildBytes(encoding.Bytes),
	HandleDefs: buildHandleDefs(encodeSuccess.HandleDefs),
	Handles: toDartIntList(encoding.Handles),
	})
	}
	}
	return encodeSuccessCases, nil
	}

	func decodeSuccessCases(gidlDecodeSuccesses []gidlir.DecodeSuccess, schema gidlmixer.Schema) ([]decodeSuccessCase, error) {
	var decodeSuccessCases []decodeSuccessCase
	for _, decodeSuccess := range gidlDecodeSuccesses {
	decl, err := schema.ExtractDeclaration(decodeSuccess.Value, decodeSuccess.HandleDefs)
	if err != nil {
	return nil, fmt.Errorf("decode success %s: %s", decodeSuccess.Name, err)
	}
	valueStr := visit(decodeSuccess.Value, decl)
	valueType := typeName(decl)
	for _, encoding := range decodeSuccess.Encodings {
	if !wireFormatSupported(encoding.WireFormat) {
	continue
	}
	decodeSuccessCases = append(decodeSuccessCases, decodeSuccessCase{
	DecoderName: decoderName(encoding.WireFormat),
	Name: testCaseName(decodeSuccess.Name, encoding.WireFormat),
	Value: valueStr,
	ValueType: valueType,
	Bytes: buildBytes(encoding.Bytes),
	HandleDefs: buildHandleDefs(decodeSuccess.HandleDefs),
	Handles: toDartIntList(encoding.Handles),
	UnusedHandles: toDartIntList(gidlir.GetUnusedHandles(decodeSuccess.Value, encoding.Handles)),
	})
	}
	}
	return decodeSuccessCases, nil
	}

	func encodeFailureCases(gidlEncodeFailures []gidlir.EncodeFailure, schema gidlmixer.Schema) ([]encodeFailureCase, error) {
	var encodeFailureCases []encodeFailureCase
	for _, encodeFailure := range gidlEncodeFailures {
	decl, err := schema.ExtractDeclarationUnsafe(encodeFailure.Value)
	if err != nil {
	return nil, fmt.Errorf("encode failure %s: %s", encodeFailure.Name, err)
	}
	if gidlir.ContainsUnknownField(encodeFailure.Value) {
	continue
	}
	errorCode, err := dartErrorCode(encodeFailure.Err)
	if err != nil {
	return nil, fmt.Errorf("encode failure %s: %s", encodeFailure.Name, err)
	}
	valueStr := visit(encodeFailure.Value, decl)
	valueType := typeName(decl)
	for _, wireFormat := range encodeFailure.WireFormats {
	if !wireFormatSupported(wireFormat) {
	continue
	}
	encodeFailureCases = append(encodeFailureCases, encodeFailureCase{
	EncoderName: encoderName(wireFormat),
	Name: testCaseName(encodeFailure.Name, wireFormat),
	Value: valueStr,
	ValueType: valueType,
	ErrorCode: errorCode,
	HandleDefs: buildHandleDefs(encodeFailure.HandleDefs),
	})
	}
	}
	return encodeFailureCases, nil
	}

	func decodeFailureCases(gidlDecodeFailures []gidlir.DecodeFailure, schema gidlmixer.Schema) ([]decodeFailureCase, error) {
	var decodeFailureCases []decodeFailureCase
	for _, decodeFailure := range gidlDecodeFailures {
	_, err := schema.ExtractDeclarationByName(decodeFailure.Type)
	if err != nil {
	return nil, fmt.Errorf("decode failure %s: %s", decodeFailure.Name, err)
	}
	errorCode, err := dartErrorCode(decodeFailure.Err)
	if err != nil {
	return nil, fmt.Errorf("decode failure %s: %s", decodeFailure.Name, err)
	}
	valueType := dartTypeName(decodeFailure.Type)
	for _, encoding := range decodeFailure.Encodings {
	if !wireFormatSupported(encoding.WireFormat) {
	continue
	}
	decodeFailureCases = append(decodeFailureCases, decodeFailureCase{
	DecoderName: decoderName(encoding.WireFormat),
	Name: testCaseName(decodeFailure.Name, encoding.WireFormat),
	ValueType: valueType,
	Bytes: buildBytes(encoding.Bytes),
	ErrorCode: errorCode,
	HandleDefs: buildHandleDefs(decodeFailure.HandleDefs),
	Handles: toDartIntList(encoding.Handles),
	})
	}
	}
	return decodeFailureCases, nil
	}

	func wireFormatSupported(wireFormat gidlir.WireFormat) bool {
	return wireFormat == gidlir.V1WireFormat
	}

	func testCaseName(baseName string, wireFormat gidlir.WireFormat) string {
	return fidl.SingleQuote(fmt.Sprintf("%s_%s", baseName, wireFormat))
	}

	func encoderName(wireFormat gidlir.WireFormat) string {
	return fmt.Sprintf("Encoders.%s", wireFormat)
	}

	func decoderName(wireFormat gidlir.WireFormat) string {
	return fmt.Sprintf("Decoders.%s", wireFormat)
	}

	func dartTypeName(inputType string) string {
	return fmt.Sprintf("k%s_Type", inputType)
	}

	func buildBytes(bytes []byte) string {
	var builder strings.Builder
	builder.WriteString("Uint8List.fromList([\n")
	for i, b := range bytes {
	builder.WriteString(fmt.Sprintf("0x%02x,", b))
	if i%8 == 7 {
	// Note: empty comments are written to preserve formatting. See:
	// https://github.com/dart-lang/dart_style/wiki/FAQ#why-does-the-formatter-mess-up-my-collection-literals
	builder.WriteString(" //\n")
	}
	}
	builder.WriteString("])")
	return builder.String()
	}

	func toDartStr(value string) string {
	var buf bytes.Buffer
	buf.WriteRune('\'')
	for _, r := range value {
	if 0x20 <= r && r <= 0x7e { // printable ASCII rune
	buf.WriteRune(r)
	} else {
	buf.WriteString(fmt.Sprintf(`\u{%x}`, r))
	}
	}
	buf.WriteRune('\'')
	return buf.String()
	}

	func toDartIntList(handles []gidlir.Handle) string {
	var builder strings.Builder
	builder.WriteString("[\n")
	for i, handle := range handles {
	builder.WriteString(fmt.Sprintf("%d,", handle))
	if i%8 == 7 {
	// Note: empty comments are written to preserve formatting. See:
	// https://github.com/dart-lang/dart_style/wiki/FAQ#why-does-the-formatter-mess-up-my-collection-literals
	builder.WriteString(" //\n")
	}
	}
	builder.WriteString("]")
	return builder.String()
	}

	// Dart error codes defined in: topaz/public/dart/fidl/lib/src/error.dart.
	var dartErrorCodeNames = map[gidlir.ErrorCode]string{
	gidlir.StringTooLong: "fidlStringTooLong",
	gidlir.StringNotUtf8: "unknown",
	gidlir.NonEmptyStringWithNullBody: "fidlNonEmptyStringWithNullBody",
	gidlir.StrictUnionFieldNotSet: "fidlStrictXUnionFieldNotSet",
	gidlir.StrictUnionUnknownField: "fidlStrictXUnionUnknownField",
	gidlir.StrictBitsUnknownBit: "fidlInvalidBit",
	gidlir.StrictEnumUnknownValue: "fidlInvalidEnumValue",
	gidlir.InvalidPaddingByte: "unknown",
	gidlir.TooFewHandles: "fidlTooFewHandles",
	gidlir.NonResourceUnknownHandles: "fidlNonResourceHandle",
	}

	func dartErrorCode(code gidlir.ErrorCode) (string, error) {
	if str, ok := dartErrorCodeNames[code]; ok {
	return fmt.Sprintf("fidl.FidlErrorCode.%s", str), nil
	}
	return "", fmt.Errorf("no dart error string defined for error code %s", code)
	}