build: update MungeTestXML and MergeTestXMLs behavior

The `test.xml` produced by `rules_go` changed with the latest upgrade;
this change restores the previous behavior.

Epic: DEVINF-1477
Closes #156597
Release note: none

Author: rickystewart

pkg/build/util/util.go

@@ -8,7 +8,6 @@
 package util
 
 import (
-	"cmp"
 	"encoding/xml"
 	"fmt"
 	"io"
@@ -30,8 +29,13 @@ type TestSuites struct {
 type testSuite struct {
 	XMLName   xml.Name    `xml:"testsuite"`
 	TestCases []*testCase `xml:"testcase"`
-	Attrs     []xml.Attr  `xml:",any,attr"`
+	Errors    int         `xml:"errors,attr"`
+	Failures  int         `xml:"failures,attr"`
+	Skipped   int         `xml:"skipped,attr"`
+	Tests     int         `xml:"tests,attr"`
+	Time      float64     `xml:"time,attr"`
 	Name      string      `xml:"name,attr"`
+	Timestamp string      `xml:"timestamp,attr"`
 }
 
 type testCase struct {
@@ -41,11 +45,12 @@ type testCase struct {
 	// this isn't Java so there isn't a classname) and excluding it causes
 	// the TeamCity UI to display the same data in a slightly more coherent
 	// and usable way.
-	Name    string      `xml:"name,attr"`
-	Time    string      `xml:"time,attr"`
-	Failure *XMLMessage `xml:"failure,omitempty"`
-	Error   *XMLMessage `xml:"error,omitempty"`
-	Skipped *XMLMessage `xml:"skipped,omitempty"`
+	Classname string      `xml:"classname,attr"`
+	Name      string      `xml:"name,attr"`
+	Time      string      `xml:"time,attr"`
+	Failure   *XMLMessage `xml:"failure,omitempty"`
+	Error     *XMLMessage `xml:"error,omitempty"`
+	Skipped   *XMLMessage `xml:"skipped,omitempty"`
 }
 
 // XMLMessage is a catch-all structure containing details about a test
@@ -122,7 +127,6 @@ func OutputsOfGenrule(target, xmlQueryOutput string) ([]string, error) {
 // it to the output file. TeamCity kind of knows how to interpret the schema,
 // but the schema isn't *exactly* what it's expecting. By munging the XML's
 // here we ensure that the TC test view is as useful as possible.
-// Helper function meant to be used with maybeStageArtifact.
 func MungeTestXML(srcContent []byte, outFile io.Writer) error {
 	// Parse the XML into a TestSuites struct.
 	suites := TestSuites{}
@@ -135,59 +139,102 @@ func MungeTestXML(srcContent []byte, outFile io.Writer) error {
 	if err != nil {
 		return err
 	}
-	// If test.xml is empty, this will be an empty object. We do want to
-	// emit something, however.
-	if len(suites.Suites) == 0 {
-		return writeToFile(&testSuite{}, outFile)
+	var res testSuite
+	for _, suite := range suites.Suites {
+		res.XMLName = suite.XMLName
+		res.TestCases = append(res.TestCases, suite.TestCases...)
+		if res.Name == "" {
+			i := strings.LastIndexByte(suite.Name, '.')
+			if i < 0 {
+				i = len(suite.Name)
+			}
+			res.Name = suite.Name[0:i]
+		}
+		res.Errors += suite.Errors
+		res.Failures += suite.Failures
+		res.Skipped += suite.Skipped
+		res.Tests += suite.Tests
+		res.Time += suite.Time
+		if res.Timestamp == "" {
+			res.Timestamp = suite.Timestamp
+		} else {
+			res.Timestamp = min(res.Timestamp, suite.Timestamp)
+		}
 	}
-	// We only want the first test suite in the list of suites.
-	return writeToFile(&suites.Suites[0], outFile)
+	return writeToFile(res, outFile)
 }
 
-// MergeTestXMLs merges the given list of test suites into a single test suite,
-// then writes the serialized XML to the given outFile. The prefix is passed
-// to xml.Unmarshal. Note that this function might modify the passed-in
-// TestSuites in-place.
+// MergeTestXMLs merges the given list of test suites into a single object,
+// then writes the serialized XML to the given outFile.
 func MergeTestXMLs(suitesToMerge []TestSuites, outFile io.Writer) error {
 	if len(suitesToMerge) == 0 {
 		return fmt.Errorf("expected at least one test suite")
 	}
-	var resultSuites TestSuites
-	resultSuites.Suites = append(resultSuites.Suites, testSuite{})
-	resultSuite := &resultSuites.Suites[0]
-	resultSuite.Name = suitesToMerge[0].Suites[0].Name
-	resultSuite.Attrs = suitesToMerge[0].Suites[0].Attrs
-	cases := make(map[string]*testCase)
+	type suiteAndCaseMap struct {
+		suite testSuite
+		cases map[string]*testCase
+	}
+	suitesMap := make(map[string]*suiteAndCaseMap)
 	for _, suites := range suitesToMerge {
-		for _, testCase := range suites.Suites[0].TestCases {
-			oldCase, ok := cases[testCase.Name]
+		for _, suite := range suites.Suites {
+			oldSuite, ok := suitesMap[suite.Name]
 			if !ok {
-				cases[testCase.Name] = testCase
+				cases := make(map[string]*testCase)
+				for _, testCase := range suite.TestCases {
+					cases[testCase.Name] = testCase
+				}
+				suitesMap[suite.Name] = &suiteAndCaseMap{
+					suite: suite,
+					cases: cases,
+				}
 				continue
 			}
-			if testCase.Failure != nil {
-				if oldCase.Failure == nil {
-					oldCase.Failure = testCase.Failure
-				} else {
-					oldCase.Failure.Contents = oldCase.Failure.Contents + "\n" + testCase.Failure.Contents
+			for _, testCase := range suite.TestCases {
+				oldCase, ok := oldSuite.cases[testCase.Name]
+				if !ok {
+					oldSuite.cases[testCase.Name] = testCase
+					continue
 				}
-			}
-			if testCase.Error != nil {
-				if oldCase.Error == nil {
-					oldCase.Error = testCase.Error
-				} else {
-					oldCase.Error.Contents = oldCase.Error.Contents + "\n" + testCase.Error.Contents
+				if testCase.Failure != nil {
+					if oldCase.Failure == nil {
+						oldCase.Failure = testCase.Failure
+						oldSuite.suite.Failures += 1
+					} else {
+						oldCase.Failure.Contents = oldCase.Failure.Contents + "\n" + testCase.Failure.Contents
+					}
+				}
+				if testCase.Error != nil {
+					if oldCase.Error == nil {
+						oldCase.Error = testCase.Error
+						oldSuite.suite.Errors += 1
+					} else {
+						oldCase.Error.Contents = oldCase.Error.Contents + "\n" + testCase.Error.Contents
+					}
 				}
 			}
 		}
 	}
-	for _, testCase := range cases {
-		resultSuite.TestCases = append(resultSuite.TestCases, testCase)
+	suitesSlice := make([]string, 0, len(suitesMap))
+	for suiteName := range suitesMap {
+		suitesSlice = append(suitesSlice, suiteName)
+	}
+	slices.Sort(suitesSlice)
+	var res TestSuites
+	for _, suiteName := range suitesSlice {
+		suiteAndCases := suitesMap[suiteName]
+		suite := suiteAndCases.suite
+		suite.TestCases = []*testCase{}
+		casesSlice := make([]string, 0, len(suiteAndCases.cases))
+		for caseName := range suiteAndCases.cases {
+			casesSlice = append(casesSlice, caseName)
+		}
+		slices.Sort(casesSlice)
+		for _, caseName := range casesSlice {
+			suite.TestCases = append(suite.TestCases, suiteAndCases.cases[caseName])
+		}
+		res.Suites = append(res.Suites, suite)
 	}
-	slices.SortFunc(resultSuite.TestCases, func(a, b *testCase) int {
-		return cmp.Compare(a.Name, b.Name)
-	})
-	return writeToFile(&resultSuites, outFile)
+	return writeToFile(&res, outFile)
 }
 
 func writeToFile(suite interface{}, outFile io.Writer) error {