feat: add AssumeNoBuildOutput option to ignore build output (#11)

* Add AssumeNoBuildOutput option

We use the go-junit-report libraries in a context where we know that the
build has already completed. As such some tests have been written that
produce output that looks like build output, but is not. This option
allows the parser to work in this context.

* Expose AssumeNoBuildOutput via assume-no-build-output flag

---------

Co-authored-by: Josh Kunz <jkz@stripe.com>

Author: joschi

internal/gojunitreport/go-junit-report.go

@@ -20,13 +20,14 @@ type parser interface {
 
 // Config contains the go-junit-report command configuration.
 type Config struct {
-	Parser        string
-	Hostname      string
-	PackageName   string
-	SkipXMLHeader bool
-	SubtestMode   gotest.SubtestMode
-	Properties    map[string]string
-	TimestampFunc func() time.Time
+	Parser              string
+	Hostname            string
+	PackageName         string
+	SkipXMLHeader       bool
+	SubtestMode         gotest.SubtestMode
+	Properties          map[string]string
+	TimestampFunc       func() time.Time
+	AssumeNoBuildOutput bool
 
 	// For debugging
 	PrintEvents bool
@@ -86,5 +87,6 @@ func (c Config) gotestOptions() []gotest.Option {
 		gotest.PackageName(c.PackageName),
 		gotest.SetSubtestMode(c.SubtestMode),
 		gotest.TimestampFunc(c.TimestampFunc),
+		gotest.AssumeNoBuildOutput(c.AssumeNoBuildOutput),
 	}
 }

main.go

@@ -22,16 +22,17 @@ var (
 )
 
 var (
-	noXMLHeader = flag.Bool("no-xml-header", false, "do not print xml header")
-	packageName = flag.String("package-name", "", "specify a default package `name` to use if output does not contain a package name")
-	setExitCode = flag.Bool("set-exit-code", false, "set exit code to 1 if tests failed")
-	version     = flag.Bool("version", false, "print version")
-	input       = flag.String("in", "", "read go test log from `file`")
-	output      = flag.String("out", "", "write XML report to `file`")
-	iocopy      = flag.Bool("iocopy", false, "copy input to stdout; can only be used in conjunction with -out")
-	properties  = make(keyValueFlag)
-	parser      = flag.String("parser", "gotest", "set input parser: gotest, gojson")
-	mode        = flag.String("subtest-mode", "", "set subtest `mode`: ignore-parent-results (subtest parents always pass), exclude-parents (subtest parents are excluded from the report)")
+	noXMLHeader         = flag.Bool("no-xml-header", false, "do not print xml header")
+	packageName         = flag.String("package-name", "", "specify a default package `name` to use if output does not contain a package name")
+	setExitCode         = flag.Bool("set-exit-code", false, "set exit code to 1 if tests failed")
+	version             = flag.Bool("version", false, "print version")
+	input               = flag.String("in", "", "read go test log from `file`")
+	output              = flag.String("out", "", "write XML report to `file`")
+	iocopy              = flag.Bool("iocopy", false, "copy input to stdout; can only be used in conjunction with -out")
+	properties          = make(keyValueFlag)
+	parser              = flag.String("parser", "gotest", "set input parser: gotest, gojson")
+	mode                = flag.String("subtest-mode", "", "set subtest `mode`: ignore-parent-results (subtest parents always pass), exclude-parents (subtest parents are excluded from the report)")
+	assumeNoBuildOutput = flag.Bool("assume-no-build-output", false, "assume the input contains no build output and everything is test output")
 
 	// debug flags
 	printEvents = flag.Bool("debug.print-events", false, "print events generated by the go test parser")
@@ -100,13 +101,14 @@ func main() {
 	hostname, _ := os.Hostname() // ignore error
 
 	config := gojunitreport.Config{
-		Parser:        *parser,
-		Hostname:      hostname,
-		PackageName:   *packageName,
-		SkipXMLHeader: *noXMLHeader,
-		SubtestMode:   subtestMode,
-		Properties:    properties,
-		PrintEvents:   *printEvents,
+		Parser:              *parser,
+		Hostname:            hostname,
+		PackageName:         *packageName,
+		SkipXMLHeader:       *noXMLHeader,
+		SubtestMode:         subtestMode,
+		Properties:          properties,
+		PrintEvents:         *printEvents,
+		AssumeNoBuildOutput: *assumeNoBuildOutput,
 	}
 	report, err := config.Run(in, out)
 	if err != nil {

parser/gotest/gotest.go

@@ -109,10 +109,21 @@ func SetSubtestMode(mode SubtestMode) Option {
 	}
 }
 
+// AssumeNoBuildOutput is an Option disables "build_output" event parsing. This
+// option is most useful when running tests that are known to build correctly,
+// or have already been built (e.g. via go test -c, or an alternative build
+// system).
+func AssumeNoBuildOutput(assumeNoBuildOutput bool) Option {
+	return func(p *Parser) {
+		p.assumeNoBuildOutput = assumeNoBuildOutput
+	}
+}
+
 // Parser is a Go test output Parser.
 type Parser struct {
-	packageName string
-	subtestMode SubtestMode
+	packageName         string
+	subtestMode         SubtestMode
+	assumeNoBuildOutput bool
 
 	timestampFunc func() time.Time
 
@@ -208,7 +219,7 @@ func (p *Parser) parseLine(line string) (events []Event) {
 		return p.benchSummary(matches[1], matches[2], matches[3], matches[4], matches[5], matches[6])
 	} else if matches := regexEndBenchmark.FindStringSubmatch(line); len(matches) == 3 {
 		return p.endBench(matches[1], matches[2])
-	} else if strings.HasPrefix(line, "# ") {
+	} else if !p.assumeNoBuildOutput && strings.HasPrefix(line, "# ") {
 		fields := strings.Fields(strings.TrimPrefix(line, "# "))
 		if len(fields) == 1 || len(fields) == 2 {
 			return p.buildOutput(fields[0])

parser/gotest/gotest_test.go

@@ -225,3 +225,40 @@ func TestParseLine(t *testing.T) {
 		})
 	}
 }
+
+func TestParseLine_AssumeNoBuildOutput(t *testing.T) {
+	tests := []parseLineTest{
+		{
+			"# package/name/failing1",
+			[]Event{{Type: "output", Data: "# package/name/failing1"}},
+		},
+		{
+			"# package/name/failing2 [package/name/failing2.test]",
+			[]Event{{Type: "output", Data: "# package/name/failing2 [package/name/failing2.test]"}},
+		},
+	}
+
+	// Include all the other tests that don't produce build_output as well, they
+	// should continue functioning normally.
+Outer:
+	for _, test := range parseLineTests {
+		for _, event := range test.events {
+			if event.Type == "build_output" {
+				continue Outer
+			}
+		}
+
+		tests = append(tests, test)
+	}
+
+	for i, test := range tests {
+		name := fmt.Sprintf("%d-%s", i, test.Name())
+		t.Run(name, func(t *testing.T) {
+			parser := NewParser(AssumeNoBuildOutput(true))
+			events := parser.parseLine(test.input)
+			if diff := cmp.Diff(test.events, events); diff != "" {
+				t.Errorf("parseLine(%q) returned unexpected events, diff (-want, +got):\n%v", test.input, diff)
+			}
+		})
+	}
+}