go/src/infra/tools/result_adapter/gtest.go - infra/infra - Git at Google

 // Copyright 2020 The LUCI Authors. All rights reserved.
 // Use of this source code is governed under the Apache License, Version 2.0
 // that can be found in the LICENSE file.

 package main

 import (
 	"bytes"
 	"context"
 	"encoding/base64"
 	"encoding/json"
 	"fmt"
 	"io"
 	"regexp"
 	"sort"
 	"strconv"
 	"strings"

 	"go.chromium.org/luci/common/errors"
 	"go.chromium.org/luci/common/logging"
 	"go.chromium.org/luci/resultdb/pbutil"
 	pb "go.chromium.org/luci/resultdb/proto/v1"
 	sinkpb "go.chromium.org/luci/resultdb/sink/proto/v1"
 )

 var (
 	// Prefixes that may be present in the test name and must be stripped before forming the base id.
 	prefixes = []string{"MANUAL_", "PRE_"}

 	// Java base ids aren't actually GTest but use the same launcher output format.
 	// TODO(chanli@): remove java test related logic when crbug.com/1104245 and crbug.com/1104238 are done.
 	javaIDRe = regexp.MustCompile(`^[\w.]+#`)

 	// Test base ids look like FooTest.DoesBar: "FooTest" is the suite and "DoesBar" the test name.
 	baseIDRE = regexp.MustCompile(`^(\w+)\.(\w+)$`)

 	// Type parametrized test examples:
 	// - MyInstantiation/FooTest/1.DoesBar
 	// - FooTest/1.DoesBar
 	// - FooType/MyType.DoesBar
 	//
 	// In the above examples, "FooTest" is the suite, "DoesBar" the test name, "MyInstantiation" the
 	// optional instantiation, "1" the index of the type on which the test has been instantiated, if
 	// no string representation for the type has been provided, and "MyType" is the user-provided
 	// string representation of the type on which the test has been instantiated.
 	typeParamRE = regexp.MustCompile(`^((\w+)/)?(\w+)/(\w+)\.(\w+)$`)

 	// Value parametrized tests examples:
 	// - MyInstantiation/FooTest.DoesBar/1
 	// - FooTest.DoesBar/1
 	// - FooTest.DoesBar/TestValue
 	//
 	// In the above examples, "FooTest" is the suite, "DoesBar" the test name, "MyInstantiation" the
 	// optional instantiation, "1" the index of the value on which the test has been instantiated, if
 	// no string representation for the value has been provided, and "TestValue" is the user-provided
 	// string representation of the value on which the test has been instantiated.
 	valueParamRE = regexp.MustCompile(`^((\w+)/)?(\w+)\.(\w+)/(\w+)$`)

 	// TODO(chanli@): Remove this after crbug.com/1045846 is fixed.
 	// This is a synthetic test created by test launcher, not a real test.
 	syntheticTestRE = regexp.MustCompile(`^GoogleTestVerification.Uninstantiated(?:Type)?ParamaterizedTestSuite<\w+>$`)

 	syntheticTestTag = errors.BoolTag{
 		Key: errors.NewTagKey("synthetic test"),
 	}
 )

 // GTestResults represents the structure as described to be generated in
 // https://cs.chromium.org/chromium/src/base/test/launcher/test_results_tracker.h?l=83&rcl=96020cfd447cb285acfa1a96c37a67ed22fa2499
 // (base::TestResultsTracker::SaveSummaryAsJSON)
 //
 // Fields not used by Test Results are omitted.
 type GTestResults struct {
 	AllTests      []string `json:"all_tests"`
 	DisabledTests []string `json:"disabled_tests"`
 	GlobalTags    []string `json:"global_tags"`

 	// PerIterationData is a vector of run iterations, each mapping test names to a list of test data.
 	PerIterationData []map[string][]*GTestRunResult `json:"per_iteration_data"`

 	// TestLocations maps test names to their location in code.
 	TestLocations map[string]*Location `json:"test_locations"`
 }

 // GTestRunResult represents the per_iteration_data as described in
 // https://cs.chromium.org/chromium/src/base/test/launcher/test_results_tracker.h?l=83&rcl=96020cfd447cb285acfa1a96c37a67ed22fa2499
 // (base::TestResultsTracker::SaveSummaryAsJSON)
 //
 // Fields not used by Test Results are omitted.
 type GTestRunResult struct {
 	Status        string  `json:"status"`
 	ElapsedTimeMs float64 `json:"elapsed_time_ms"`

 	LosslessSnippet     bool   `json:"losless_snippet"`
 	OutputSnippetBase64 string `json:"output_snippet_base64"`

 	// Links are not generated by test_launcher, but harnesses built on top may add them to the json.
 	Links map[string]json.RawMessage `json:"links"`
 }

 // Location describes a code location.
 type Location struct {
 	File string `json:"file"`
 	Line int    `json:"line"`
 }

 // Link represents a link content.
 type Link struct {
 	Content string `json:"content"`
 }

 // ConvertFromJSON reads the provided reader into the receiver.
 //
 // The receiver is cleared and its fields overwritten.
 func (r *GTestResults) ConvertFromJSON(reader io.Reader) error {
 	*r = GTestResults{}
 	if err := json.NewDecoder(reader).Decode(r); err != nil {
 		return err
 	}

 	return nil
 }

 // ToProtos converts test results in r to []*sinkpb.TestResult.
 func (r *GTestResults) ToProtos(ctx context.Context) ([]*sinkpb.TestResult, error) {
 	var ret []*sinkpb.TestResult
 	var testNames []string

 	globalTags := make([]*pb.StringPair, len(r.GlobalTags)+1)
 	for i, tag := range r.GlobalTags {
 		globalTags[i] = pbutil.StringPair("gtest_global_tag", tag)
 	}
 	globalTags[len(r.GlobalTags)] = pbutil.StringPair(originalFormatTagKey, formatGTest)

 	for _, name := range r.DisabledTests {
 		testID, err := extractGTestParameters(name)
 		switch {
 		case syntheticTestTag.In(err):
 			continue
 		case err != nil:
 			return nil, errors.Annotate(err,
 				"failed to extract test id and parameters from %q", name).Err()
 		}
 		tr := &sinkpb.TestResult{
 			TestId:   testID,
 			Expected: true,
 			Status:   pb.TestStatus_SKIP,
 			Tags: pbutil.StringPairs(
 				// Store the original Gtest test name.
 				"test_name", name,
 				"disabled_test", "true",
 			),
 			TestMetadata: &pb.TestMetadata{Name: name},
 		}
 		tr.Tags = append(tr.Tags, globalTags...)

 		ret = append(ret, tr)
 	}

 	var buf bytes.Buffer
 	for _, data := range r.PerIterationData {
 		// Sort the test name to make the output deterministic.
 		testNames = testNames[:0]
 		for name := range data {
 			testNames = append(testNames, name)
 		}
 		sort.Strings(testNames)

 		for _, name := range testNames {
 			testID, err := extractGTestParameters(name)
 			switch {
 			case syntheticTestTag.In(err):
 				continue
 			case err != nil:
 				return nil, errors.Annotate(err,
 					"failed to extract test id and parameters from %q", name).Err()
 			}

 			for i, result := range data[name] {
 				// Store the processed test result into the correct part of the overall map.
 				rpb, err := r.convertTestResult(ctx, &buf, testID, name, result)
 				if err != nil {
 					return nil, errors.Annotate(err,
 						"iteration %d of test %s failed to convert run result", i, name).Err()
 				}
 				rpb.Tags = append(rpb.Tags, globalTags...)

 				ret = append(ret, rpb)
 			}
 		}
 	}

 	return ret, nil
 }

 func fromGTestStatus(s string) (status pb.TestStatus, expected bool, err error) {
 	switch s {
 	case "SUCCESS":
 		return pb.TestStatus_PASS, true, nil
 	case "FAILURE":
 		return pb.TestStatus_FAIL, false, nil
 	case "FAILURE_ON_EXIT":
 		return pb.TestStatus_FAIL, false, nil
 	case "TIMEOUT":
 		return pb.TestStatus_ABORT, false, nil
 	case "CRASH":
 		return pb.TestStatus_CRASH, false, nil
 	case "SKIPPED":
 		return pb.TestStatus_SKIP, true, nil
 	case "EXCESSIVE_OUTPUT":
 		return pb.TestStatus_FAIL, false, nil
 	case "NOTRUN":
 		return pb.TestStatus_SKIP, false, nil
 	case "UNKNOWN":
 		return pb.TestStatus_ABORT, false, nil
 	default:
 		// This would only happen if the set of possible GTest result statuses change and resultsdb has
 		// not been updated to match.
 		return pb.TestStatus_STATUS_UNSPECIFIED, false, errors.Reason("unknown GTest status %q", s).Err()
 	}
 }

 // extractGTestParameters extracts parameters from a test id as a mapping with "param/" keys.
 func extractGTestParameters(testID string) (baseID string, err error) {
 	var suite, name, instantiation, id string

 	// If this is a JUnit tests, don't try to extract parameters.
 	if match := javaIDRe.FindStringSubmatch(testID); match != nil {
 		baseID = testID
 		return
 	}

 	// Tests can be only one of type- or value-parametrized, if parametrized at all.
 	if match := typeParamRE.FindStringSubmatch(testID); match != nil {
 		// Extract type parameter.
 		suite = match[3]
 		name = match[5]
 		instantiation = match[2]
 		id = match[4]
 	} else if match := valueParamRE.FindStringSubmatch(testID); match != nil {
 		// Extract value parameter.
 		suite = match[3]
 		name = match[4]
 		instantiation = match[2]
 		id = match[5]
 	} else if match := baseIDRE.FindStringSubmatch(testID); match != nil {
 		// Otherwise our test id should not be parametrized, so extract the suite
 		// and name.
 		suite = match[1]
 		name = match[2]
 	} else if syntheticTestRE.MatchString(testID) {
 		// A synthetic test, skip.
 		err = errors.Reason("not a real test").Tag(syntheticTestTag).Err()
 	} else {
 		// Otherwise test id format is unrecognized.
 		err = errors.Reason("test id of unknown format").Err()
 		return
 	}

 	// Strip prefixes from test name if necessary.
 	name = stripRepeatedPrefixes(name, prefixes...)

 	switch {
 	case id == "":
 		baseID = fmt.Sprintf("%s.%s", suite, name)
 	case instantiation == "":
 		baseID = fmt.Sprintf("%s.%s/%s", suite, name, id)
 	default:
 		baseID = fmt.Sprintf("%s.%s/%s.%s", suite, name, instantiation, id)
 	}

 	return
 }

 func (r *GTestResults) convertTestResult(ctx context.Context, buf *bytes.Buffer, testID, name string, result *GTestRunResult) (*sinkpb.TestResult, error) {
 	status, expected, err := fromGTestStatus(result.Status)
 	if err != nil {
 		return nil, err
 	}

 	tr := &sinkpb.TestResult{
 		TestId:   testID,
 		Expected: expected,
 		Status:   status,
 		Tags: pbutil.StringPairs(
 			// Store the original Gtest test name.
 			"test_name", name,
 			// Store the original GTest status.
 			"gtest_status", result.Status,
 			// Store the correct output snippet.
 			"lossless_snippet", strconv.FormatBool(result.LosslessSnippet),
 		),
 		TestMetadata: &pb.TestMetadata{Name: name},
 	}

 	// Do not set duration if it is unknown.
 	if result.ElapsedTimeMs != 0 {
 		tr.Duration = msToDuration(result.ElapsedTimeMs)
 	}

 	summaryData := map[string]interface{}{}

 	// snippet
 	if result.OutputSnippetBase64 != "" {
 		outputBytes, err := base64.StdEncoding.DecodeString(result.OutputSnippetBase64)
 		if err != nil {
 			// Log the error, but we shouldn't fail to convert a file just because we can't
 			// convert a summary.
 			logging.Warningf(ctx, "Failed to convert OutputSnippetBase64 %q", result.OutputSnippetBase64)
 		} else {
 			tr.Artifacts = map[string]*sinkpb.Artifact{"snippet": {
 				Body:        &sinkpb.Artifact_Contents{Contents: outputBytes},
 				ContentType: "text/plain",
 			}}
 			summaryData["text_artifacts"] = []string{"snippet"}
 		}
 	}

 	// links
 	if len(result.Links) > 0 {
 		links := make(map[string]string, len(result.Links))
 		l := new(Link)
 		s := new(string)

 		for lName, link := range result.Links {
 			switch {
 			case json.Unmarshal(link, l) == nil:
 				links[lName] = l.Content
 			case json.Unmarshal(link, s) == nil:
 				links[lName] = *s
 			default:
 				return nil, errors.Reason("unsupported data format for a link: %q", string(link)).Err()
 			}
 		}
 		summaryData["links"] = links
 	}

 	// Write the summary html
 	if len(summaryData) > 0 {
 		buf.Reset()
 		if err := summaryTmpl.ExecuteTemplate(buf, "gtest", summaryData); err != nil {
 			return nil, err
 		}
 		tr.SummaryHtml = buf.String()
 	}

 	// Store the test code location.
 	if loc, ok := r.TestLocations[name]; ok {
 		file := normalizePath(loc.File)
 		// For some reason, many file paths start with "../../", followed by
 		// the correct path. Strip the prefix.
 		file = stripRepeatedPrefixes(file, "../")
 		file = ensureLeadingDoubleSlash(file)
 		tr.TestMetadata.Location = &pb.TestLocation{
 			Repo:     chromiumSrcRepo,
 			FileName: file,
 			Line:     int32(loc.Line),
 		}
 	}

 	return tr, nil
 }

 // stripRepeatedPrefixes strips prefixes.
 func stripRepeatedPrefixes(str string, prefixes ...string) string {
 	for {
 		stripped := str
 		for _, prefix := range prefixes {
 			stripped = strings.TrimPrefix(stripped, prefix)
 		}
 		if stripped == str {
 			return str
 		}
 		str = stripped
 	}
 }
	// Copyright 2020 The LUCI Authors. All rights reserved.
	// Use of this source code is governed under the Apache License, Version 2.0
	// that can be found in the LICENSE file.

	package main

	import (
	"bytes"
	"context"
	"encoding/base64"
	"encoding/json"
	"fmt"
	"io"
	"regexp"
	"sort"
	"strconv"
	"strings"

	"go.chromium.org/luci/common/errors"
	"go.chromium.org/luci/common/logging"
	"go.chromium.org/luci/resultdb/pbutil"
	pb "go.chromium.org/luci/resultdb/proto/v1"
	sinkpb "go.chromium.org/luci/resultdb/sink/proto/v1"
	)

	var (
	// Prefixes that may be present in the test name and must be stripped before forming the base id.
	prefixes = []string{"MANUAL_", "PRE_"}

	// Java base ids aren't actually GTest but use the same launcher output format.
	// TODO(chanli@): remove java test related logic when crbug.com/1104245 and crbug.com/1104238 are done.
	javaIDRe = regexp.MustCompile(`^[\w.]+#`)

	// Test base ids look like FooTest.DoesBar: "FooTest" is the suite and "DoesBar" the test name.
	baseIDRE = regexp.MustCompile(`^(\w+)\.(\w+)$`)

	// Type parametrized test examples:
	// - MyInstantiation/FooTest/1.DoesBar
	// - FooTest/1.DoesBar
	// - FooType/MyType.DoesBar
	//
	// In the above examples, "FooTest" is the suite, "DoesBar" the test name, "MyInstantiation" the
	// optional instantiation, "1" the index of the type on which the test has been instantiated, if
	// no string representation for the type has been provided, and "MyType" is the user-provided
	// string representation of the type on which the test has been instantiated.
	typeParamRE = regexp.MustCompile(`^((\w+)/)?(\w+)/(\w+)\.(\w+)$`)

	// Value parametrized tests examples:
	// - MyInstantiation/FooTest.DoesBar/1
	// - FooTest.DoesBar/1
	// - FooTest.DoesBar/TestValue
	//
	// In the above examples, "FooTest" is the suite, "DoesBar" the test name, "MyInstantiation" the
	// optional instantiation, "1" the index of the value on which the test has been instantiated, if
	// no string representation for the value has been provided, and "TestValue" is the user-provided
	// string representation of the value on which the test has been instantiated.
	valueParamRE = regexp.MustCompile(`^((\w+)/)?(\w+)\.(\w+)/(\w+)$`)

	// TODO(chanli@): Remove this after crbug.com/1045846 is fixed.
	// This is a synthetic test created by test launcher, not a real test.
	syntheticTestRE = regexp.MustCompile(`^GoogleTestVerification.Uninstantiated(?:Type)?ParamaterizedTestSuite<\w+>$`)

	syntheticTestTag = errors.BoolTag{
	Key: errors.NewTagKey("synthetic test"),
	}
	)

	// GTestResults represents the structure as described to be generated in
	// https://cs.chromium.org/chromium/src/base/test/launcher/test_results_tracker.h?l=83&rcl=96020cfd447cb285acfa1a96c37a67ed22fa2499
	// (base::TestResultsTracker::SaveSummaryAsJSON)
	//
	// Fields not used by Test Results are omitted.
	type GTestResults struct {
	AllTests []string `json:"all_tests"`
	DisabledTests []string `json:"disabled_tests"`
	GlobalTags []string `json:"global_tags"`

	// PerIterationData is a vector of run iterations, each mapping test names to a list of test data.
	PerIterationData []map[string][]*GTestRunResult `json:"per_iteration_data"`

	// TestLocations maps test names to their location in code.
	TestLocations map[string]*Location `json:"test_locations"`
	}

	// GTestRunResult represents the per_iteration_data as described in
	// https://cs.chromium.org/chromium/src/base/test/launcher/test_results_tracker.h?l=83&rcl=96020cfd447cb285acfa1a96c37a67ed22fa2499
	// (base::TestResultsTracker::SaveSummaryAsJSON)
	//
	// Fields not used by Test Results are omitted.
	type GTestRunResult struct {
	Status string `json:"status"`
	ElapsedTimeMs float64 `json:"elapsed_time_ms"`

	LosslessSnippet bool `json:"losless_snippet"`
	OutputSnippetBase64 string `json:"output_snippet_base64"`

	// Links are not generated by test_launcher, but harnesses built on top may add them to the json.
	Links map[string]json.RawMessage `json:"links"`
	}

	// Location describes a code location.
	type Location struct {
	File string `json:"file"`
	Line int `json:"line"`
	}

	// Link represents a link content.
	type Link struct {
	Content string `json:"content"`
	}

	// ConvertFromJSON reads the provided reader into the receiver.
	//
	// The receiver is cleared and its fields overwritten.
	func (r *GTestResults) ConvertFromJSON(reader io.Reader) error {
	*r = GTestResults{}
	if err := json.NewDecoder(reader).Decode(r); err != nil {
	return err
	}

	return nil
	}

	// ToProtos converts test results in r to []*sinkpb.TestResult.
	func (r GTestResults) ToProtos(ctx context.Context) ([]sinkpb.TestResult, error) {
	var ret []*sinkpb.TestResult
	var testNames []string

	globalTags := make([]*pb.StringPair, len(r.GlobalTags)+1)
	for i, tag := range r.GlobalTags {
	globalTags[i] = pbutil.StringPair("gtest_global_tag", tag)
	}
	globalTags[len(r.GlobalTags)] = pbutil.StringPair(originalFormatTagKey, formatGTest)

	for _, name := range r.DisabledTests {
	testID, err := extractGTestParameters(name)
	switch {
	case syntheticTestTag.In(err):
	continue
	case err != nil:
	return nil, errors.Annotate(err,
	"failed to extract test id and parameters from %q", name).Err()
	}
	tr := &sinkpb.TestResult{
	TestId: testID,
	Expected: true,
	Status: pb.TestStatus_SKIP,
	Tags: pbutil.StringPairs(
	// Store the original Gtest test name.
	"test_name", name,
	"disabled_test", "true",
	),
	TestMetadata: &pb.TestMetadata{Name: name},
	}
	tr.Tags = append(tr.Tags, globalTags...)

	ret = append(ret, tr)
	}

	var buf bytes.Buffer
	for _, data := range r.PerIterationData {
	// Sort the test name to make the output deterministic.
	testNames = testNames[:0]
	for name := range data {
	testNames = append(testNames, name)
	}
	sort.Strings(testNames)

	for _, name := range testNames {
	testID, err := extractGTestParameters(name)
	switch {
	case syntheticTestTag.In(err):
	continue
	case err != nil:
	return nil, errors.Annotate(err,
	"failed to extract test id and parameters from %q", name).Err()
	}

	for i, result := range data[name] {
	// Store the processed test result into the correct part of the overall map.
	rpb, err := r.convertTestResult(ctx, &buf, testID, name, result)
	if err != nil {
	return nil, errors.Annotate(err,
	"iteration %d of test %s failed to convert run result", i, name).Err()
	}
	rpb.Tags = append(rpb.Tags, globalTags...)

	ret = append(ret, rpb)
	}
	}
	}

	return ret, nil
	}

	func fromGTestStatus(s string) (status pb.TestStatus, expected bool, err error) {
	switch s {
	case "SUCCESS":
	return pb.TestStatus_PASS, true, nil
	case "FAILURE":
	return pb.TestStatus_FAIL, false, nil
	case "FAILURE_ON_EXIT":
	return pb.TestStatus_FAIL, false, nil
	case "TIMEOUT":
	return pb.TestStatus_ABORT, false, nil
	case "CRASH":
	return pb.TestStatus_CRASH, false, nil
	case "SKIPPED":
	return pb.TestStatus_SKIP, true, nil
	case "EXCESSIVE_OUTPUT":
	return pb.TestStatus_FAIL, false, nil
	case "NOTRUN":
	return pb.TestStatus_SKIP, false, nil
	case "UNKNOWN":
	return pb.TestStatus_ABORT, false, nil
	default:
	// This would only happen if the set of possible GTest result statuses change and resultsdb has
	// not been updated to match.
	return pb.TestStatus_STATUS_UNSPECIFIED, false, errors.Reason("unknown GTest status %q", s).Err()
	}
	}

	// extractGTestParameters extracts parameters from a test id as a mapping with "param/" keys.
	func extractGTestParameters(testID string) (baseID string, err error) {
	var suite, name, instantiation, id string

	// If this is a JUnit tests, don't try to extract parameters.
	if match := javaIDRe.FindStringSubmatch(testID); match != nil {
	baseID = testID
	return
	}

	// Tests can be only one of type- or value-parametrized, if parametrized at all.
	if match := typeParamRE.FindStringSubmatch(testID); match != nil {
	// Extract type parameter.
	suite = match[3]
	name = match[5]
	instantiation = match[2]
	id = match[4]
	} else if match := valueParamRE.FindStringSubmatch(testID); match != nil {
	// Extract value parameter.
	suite = match[3]
	name = match[4]
	instantiation = match[2]
	id = match[5]
	} else if match := baseIDRE.FindStringSubmatch(testID); match != nil {
	// Otherwise our test id should not be parametrized, so extract the suite
	// and name.
	suite = match[1]
	name = match[2]
	} else if syntheticTestRE.MatchString(testID) {
	// A synthetic test, skip.
	err = errors.Reason("not a real test").Tag(syntheticTestTag).Err()
	} else {
	// Otherwise test id format is unrecognized.
	err = errors.Reason("test id of unknown format").Err()
	return
	}

	// Strip prefixes from test name if necessary.
	name = stripRepeatedPrefixes(name, prefixes...)

	switch {
	case id == "":
	baseID = fmt.Sprintf("%s.%s", suite, name)
	case instantiation == "":
	baseID = fmt.Sprintf("%s.%s/%s", suite, name, id)
	default:
	baseID = fmt.Sprintf("%s.%s/%s.%s", suite, name, instantiation, id)
	}

	return
	}

	func (r GTestResults) convertTestResult(ctx context.Context, buf bytes.Buffer, testID, name string, result GTestRunResult) (sinkpb.TestResult, error) {
	status, expected, err := fromGTestStatus(result.Status)
	if err != nil {
	return nil, err
	}

	tr := &sinkpb.TestResult{
	TestId: testID,
	Expected: expected,
	Status: status,
	Tags: pbutil.StringPairs(
	// Store the original Gtest test name.
	"test_name", name,
	// Store the original GTest status.
	"gtest_status", result.Status,
	// Store the correct output snippet.
	"lossless_snippet", strconv.FormatBool(result.LosslessSnippet),
	),
	TestMetadata: &pb.TestMetadata{Name: name},
	}

	// Do not set duration if it is unknown.
	if result.ElapsedTimeMs != 0 {
	tr.Duration = msToDuration(result.ElapsedTimeMs)
	}

	summaryData := map[string]interface{}{}

	// snippet
	if result.OutputSnippetBase64 != "" {
	outputBytes, err := base64.StdEncoding.DecodeString(result.OutputSnippetBase64)
	if err != nil {
	// Log the error, but we shouldn't fail to convert a file just because we can't
	// convert a summary.
	logging.Warningf(ctx, "Failed to convert OutputSnippetBase64 %q", result.OutputSnippetBase64)
	} else {
	tr.Artifacts = map[string]*sinkpb.Artifact{"snippet": {
	Body: &sinkpb.Artifact_Contents{Contents: outputBytes},
	ContentType: "text/plain",
	}}
	summaryData["text_artifacts"] = []string{"snippet"}
	}
	}

	// links
	if len(result.Links) > 0 {
	links := make(map[string]string, len(result.Links))
	l := new(Link)
	s := new(string)

	for lName, link := range result.Links {
	switch {
	case json.Unmarshal(link, l) == nil:
	links[lName] = l.Content
	case json.Unmarshal(link, s) == nil:
	links[lName] = *s
	default:
	return nil, errors.Reason("unsupported data format for a link: %q", string(link)).Err()
	}
	}
	summaryData["links"] = links
	}

	// Write the summary html
	if len(summaryData) > 0 {
	buf.Reset()
	if err := summaryTmpl.ExecuteTemplate(buf, "gtest", summaryData); err != nil {
	return nil, err
	}
	tr.SummaryHtml = buf.String()
	}

	// Store the test code location.
	if loc, ok := r.TestLocations[name]; ok {
	file := normalizePath(loc.File)
	// For some reason, many file paths start with "../../", followed by
	// the correct path. Strip the prefix.
	file = stripRepeatedPrefixes(file, "../")
	file = ensureLeadingDoubleSlash(file)
	tr.TestMetadata.Location = &pb.TestLocation{
	Repo: chromiumSrcRepo,
	FileName: file,
	Line: int32(loc.Line),
	}
	}

	return tr, nil
	}

	// stripRepeatedPrefixes strips prefixes.
	func stripRepeatedPrefixes(str string, prefixes ...string) string {
	for {
	stripped := str
	for _, prefix := range prefixes {
	stripped = strings.TrimPrefix(stripped, prefix)
	}
	if stripped == str {
	return str
	}
	str = stripped
	}
	}