testing: print test results to standard output

Errors in the code under test go to standard output.
Errors in testing or its usage go to standard error.

R=r
CC=golang-dev
https://golang.org/cl/5374090

src/pkg/testing/benchmark.go

@@ -205,7 +205,7 @@ func RunBenchmarks(matchString func(pat, str string) (bool, error), benchmarks [
 	for _, Benchmark := range benchmarks {
 		matched, err := matchString(*matchBenchmarks, Benchmark.Name)
 		if err != nil {
-			println("invalid regexp for -test.bench:", err.Error())
+			fmt.Fprintf(os.Stderr, "testing: invalid regexp for -test.bench: %s\n", err)
 			os.Exit(1)
 		}
 		if !matched {
@@ -218,11 +218,11 @@ func RunBenchmarks(matchString func(pat, str string) (bool, error), benchmarks [
 			if procs != 1 {
 				benchName = fmt.Sprintf("%s-%d", Benchmark.Name, procs)
 			}
-			print(fmt.Sprintf("%s\t", benchName))
+			fmt.Printf("%s\t", benchName)
 			r := b.run()
-			print(fmt.Sprintf("%v\n", r))
+			fmt.Printf("%v\n", r)
 			if p := runtime.GOMAXPROCS(-1); p != procs {
-				print(fmt.Sprintf("%s left GOMAXPROCS set to %d\n", benchName, p))
+				fmt.Fprintf(os.Stderr, "testing: %s left GOMAXPROCS set to %d\n", benchName, p)
 			}
 		}
 	}

src/pkg/testing/example.go

@@ -21,24 +21,23 @@ type InternalExample struct {
 func RunExamples(examples []InternalExample) (ok bool) {
 	ok = true
 
+	var eg InternalExample
+
 	stdout, stderr := os.Stdout, os.Stderr
 	defer func() {
 		os.Stdout, os.Stderr = stdout, stderr
 		if e := recover(); e != nil {
-			if err, ok := e.(error); ok {
-				fmt.Fprintln(os.Stderr, err)
-				os.Exit(1)
-			}
-			panic(e)
+			fmt.Printf("--- FAIL: %s\npanic: %v\n", eg.Name, e)
+			os.Exit(1)
 		}
 	}()
 
-	for _, eg := range examples {
+	for _, eg = range examples {
 		if *chatty {
-			fmt.Fprintln(os.Stderr, "=== RUN:", eg.Name)
+			fmt.Printf("=== RUN: %s\n", eg.Name)
 		}
 
-		// capture stdout and stderr for testing purposes
+		// capture stdout and stderr
 		r, w, err := os.Pipe()
 		if err != nil {
 			fmt.Fprintln(os.Stderr, err)
@@ -50,7 +49,7 @@ func RunExamples(examples []InternalExample) (ok bool) {
 			buf := new(bytes.Buffer)
 			_, err := io.Copy(buf, r)
 			if err != nil {
-				fmt.Fprintln(os.Stderr, err)
+				fmt.Fprintf(stderr, "testing: copying pipe: %v\n", err)
 				os.Exit(1)
 			}
 			outC <- buf.String()
@@ -67,16 +66,15 @@ func RunExamples(examples []InternalExample) (ok bool) {
 		out := <-outC
 
 		// report any errors
+		tstr := fmt.Sprintf("(%.2f seconds)", float64(ns)/1e9)
 		if out != eg.Output {
-			fmt.Fprintf(
-				os.Stderr,
-				"--- FAIL: %s\ngot:\n%s\nwant:\n%s\n",
-				eg.Name, out, eg.Output,
+			fmt.Printf(
+				"--- FAIL: %s %s\ngot:\n%s\nwant:\n%s\n",
+				eg.Name, tstr, out, eg.Output,
 			)
 			ok = false
 		} else if *chatty {
-			tstr := fmt.Sprintf("(%.2f seconds)", float64(ns)/1e9)
-			fmt.Fprintln(os.Stderr, "--- PASS:", eg.Name, tstr)
+			fmt.Printf("--- PASS: %s %s\n", eg.Name, tstr)
 		}
 	}
 

src/pkg/testing/testing.go

@@ -201,10 +201,10 @@ func Main(matchString func(pat, str string) (bool, error), tests []InternalTest,
 	testOk := RunTests(matchString, tests)
 	exampleOk := RunExamples(examples)
 	if !testOk || !exampleOk {
-		fmt.Fprintln(os.Stderr, "FAIL")
+		fmt.Println("FAIL")
 		os.Exit(1)
 	}
-	fmt.Fprintln(os.Stderr, "PASS")
+	fmt.Println("PASS")
 	stopAlarm()
 	RunBenchmarks(matchString, benchmarks)
 	after()
@@ -214,9 +214,9 @@ func report(t *T) {
 	tstr := fmt.Sprintf("(%.2f seconds)", float64(t.ns)/1e9)
 	format := "--- %s: %s %s\n%s"
 	if t.failed {
-		fmt.Fprintf(os.Stderr, format, "FAIL", t.name, tstr, t.errors)
+		fmt.Printf(format, "FAIL", t.name, tstr, t.errors)
 	} else if *chatty {
-		fmt.Fprintf(os.Stderr, format, "PASS", t.name, tstr, t.errors)
+		fmt.Printf(format, "PASS", t.name, tstr, t.errors)
 	}
 }
 
@@ -236,7 +236,7 @@ func RunTests(matchString func(pat, str string) (bool, error), tests []InternalT
 		for i := 0; i < len(tests); i++ {
 			matched, err := matchString(*match, tests[i].Name)
 			if err != nil {
-				println("invalid regexp for -test.run:", err.Error())
+				fmt.Fprintf(os.Stderr, "testing: invalid regexp for -test.run: %s\n", err)
 				os.Exit(1)
 			}
 			if !matched {
@@ -248,7 +248,7 @@ func RunTests(matchString func(pat, str string) (bool, error), tests []InternalT
 			}
 			t := &T{ch: ch, name: testName, startParallel: startParallel}
 			if *chatty {
-				println("=== RUN", t.name)
+				fmt.Printf("=== RUN %s\n", t.name)
 			}
 			go tRunner(t, &tests[i])
 			out := <-t.ch
@@ -344,7 +344,7 @@ func parseCpuList() {
 		for _, val := range strings.Split(*cpuListStr, ",") {
 			cpu, err := strconv.Atoi(val)
 			if err != nil || cpu <= 0 {
-				println("invalid value for -test.cpu")
+				fmt.Fprintf(os.Stderr, "testing: invalid value %q for -test.cpu", val)
 				os.Exit(1)
 			}
 			cpuList = append(cpuList, cpu)