feat(internal/utesting): port test suite from geth

internal/utesting/utesting.go

@@ -35,6 +35,7 @@ import (
 type Test struct {
 	Name string
 	Fn   func(*T)
+	Slow bool
 }
 
 // Result is the result of a test execution.
@@ -63,32 +64,165 @@ func MatchTests(tests []Test, expr string) []Test {
 // RunTests executes all given tests in order and returns their results.
 // If the report writer is non-nil, a test report is written to it in real time.
 func RunTests(tests []Test, report io.Writer) []Result {
-	results := make([]Result, len(tests))
+	if report == nil {
+		report = io.Discard
+	}
+	results := run(tests, newConsoleOutput(report))
+	fails := CountFailures(results)
+	fmt.Fprintf(report, "%v/%v tests passed.\n", len(tests)-fails, len(tests))
+	return results
+}
+
+// RunTAP runs the given tests and writes Test Anything Protocol output
+// to the report writer.
+func RunTAP(tests []Test, report io.Writer) []Result {
+	return run(tests, newTAP(report, len(tests)))
+}
+
+func run(tests []Test, output testOutput) []Result {
+	var results = make([]Result, len(tests))
 	for i, test := range tests {
-		var output io.Writer
 		buffer := new(bytes.Buffer)
-		output = buffer
-		if report != nil {
-			output = io.MultiWriter(buffer, report)
-		}
+		logOutput := io.MultiWriter(buffer, output)
+
+		output.testStart(test.Name)
 		start := time.Now()
 		results[i].Name = test.Name
-		results[i].Failed = run(test, output)
+		results[i].Failed = runTest(test, logOutput)
 		results[i].Duration = time.Since(start)
 		results[i].Output = buffer.String()
-		if report != nil {
-			printResult(results[i], report)
-		}
+		output.testResult(results[i])
 	}
 	return results
 }
 
-func printResult(r Result, w io.Writer) {
+// testOutput is implemented by output formats.
+type testOutput interface {
+	testStart(name string)
+	Write([]byte) (int, error)
+	testResult(Result)
+}
+
+// consoleOutput prints test results similarly to go test.
+type consoleOutput struct {
+	out         io.Writer
+	indented    *indentWriter
+	curTest     string
+	wroteHeader bool
+}
+
+func newConsoleOutput(w io.Writer) *consoleOutput {
+	return &consoleOutput{
+		out:      w,
+		indented: newIndentWriter(" ", w),
+	}
+}
+
+// testStart signals the start of a new test.
+func (c *consoleOutput) testStart(name string) {
+	c.curTest = name
+	c.wroteHeader = false
+}
+
+// Write handles test log output.
+func (c *consoleOutput) Write(b []byte) (int, error) {
+	if !c.wroteHeader {
+		// This is the first output line from the test. Print a "-- RUN" header.
+		fmt.Fprintln(c.out, "-- RUN", c.curTest)
+		c.wroteHeader = true
+	}
+	return c.indented.Write(b)
+}
+
+// testResult prints the final test result line.
+func (c *consoleOutput) testResult(r Result) {
+	c.indented.flush()
 	pd := r.Duration.Truncate(100 * time.Microsecond)
 	if r.Failed {
-		fmt.Fprintf(w, "-- FAIL %s (%v)\n", r.Name, pd)
+		fmt.Fprintf(c.out, "-- FAIL %s (%v)\n", r.Name, pd)
 	} else {
-		fmt.Fprintf(w, "-- OK %s (%v)\n", r.Name, pd)
+		fmt.Fprintf(c.out, "-- OK %s (%v)\n", r.Name, pd)
+	}
+}
+
+// tapOutput produces Test Anything Protocol v13 output.
+type tapOutput struct {
+	out      io.Writer
+	indented *indentWriter
+	counter  int
+}
+
+func newTAP(out io.Writer, numTests int) *tapOutput {
+	fmt.Fprintf(out, "1..%d\n", numTests)
+	return &tapOutput{
+		out:      out,
+		indented: newIndentWriter("# ", out),
+	}
+}
+
+func (t *tapOutput) testStart(name string) {
+	t.counter++
+}
+
+// Write does nothing for TAP because there is no real-time output of test logs.
+func (t *tapOutput) Write(b []byte) (int, error) {
+	return len(b), nil
+}
+
+func (t *tapOutput) testResult(r Result) {
+	status := "ok"
+	if r.Failed {
+		status = "not ok"
+	}
+	fmt.Fprintln(t.out, status, t.counter, r.Name)
+	t.indented.Write([]byte(r.Output))
+	t.indented.flush()
+}
+
+// indentWriter indents all written text.
+type indentWriter struct {
+	out    io.Writer
+	indent string
+	inLine bool
+}
+
+func newIndentWriter(indent string, out io.Writer) *indentWriter {
+	return &indentWriter{out: out, indent: indent}
+}
+
+func (w *indentWriter) Write(b []byte) (n int, err error) {
+	for len(b) > 0 {
+		if !w.inLine {
+			if _, err = io.WriteString(w.out, w.indent); err != nil {
+				return n, err
+			}
+			w.inLine = true
+		}
+
+		end := bytes.IndexByte(b, '\n')
+		if end == -1 {
+			nn, err := w.out.Write(b)
+			n += nn
+			return n, err
+		}
+
+		line := b[:end+1]
+		nn, err := w.out.Write(line)
+		n += nn
+		if err != nil {
+			return n, err
+		}
+		b = b[end+1:]
+		w.inLine = false
+	}
+	return n, err
+}
+
+// flush ensures the current line is terminated.
+func (w *indentWriter) flush() {
+	if w.inLine {
+		fmt.Println(w.out)
+		w.inLine = false
 	}
 }
 
@@ -106,11 +240,11 @@ func CountFailures(rr []Result) int {
 // Run executes a single test.
 func Run(test Test) (bool, string) {
 	output := new(bytes.Buffer)
-	failed := run(test, output)
+	failed := runTest(test, output)
 	return failed, output.String()
 }
 
-func run(test Test, output io.Writer) bool {
+func runTest(test Test, output io.Writer) bool {
 	t := &T{output: output}
 	done := make(chan struct{})
 	go func() {
@@ -137,6 +271,9 @@ type T struct {
 	output io.Writer
 }
 
+// Helper exists for compatibility with testing.T.
+func (t *T) Helper() {}
+
 // FailNow marks the test as having failed and stops its execution by calling
 // runtime.Goexit (which then runs all deferred calls in the current goroutine).
 func (t *T) FailNow() {

internal/utesting/utesting_test.go

@@ -0,0 +1,145 @@
+// Copyright 2020 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package utesting
+
+import (
+	"bytes"
+	"regexp"
+	"strings"
+	"testing"
+)
+
+func TestTest(t *testing.T) {
+	t.Parallel()
+
+	tests := []Test{
+		{
+			Name: "successful test",
+			Fn:   func(t *T) {},
+		},
+		{
+			Name: "failing test",
+			Fn: func(t *T) {
+				t.Log("output")
+				t.Error("failed")
+			},
+		},
+		{
+			Name: "panicking test",
+			Fn: func(t *T) {
+				panic("oh no")
+			},
+		},
+	}
+	results := RunTests(tests, nil)
+
+	if results[0].Failed || results[0].Output != "" {
+		t.Fatalf("wrong result for successful test: %#v", results[0])
+	}
+	if !results[1].Failed || results[1].Output != "output\nfailed\n" {
+		t.Fatalf("wrong result for failing test: %#v", results[1])
+	}
+	if !results[2].Failed || !strings.HasPrefix(results[2].Output, "panic: oh no\n") {
+		t.Fatalf("wrong result for panicking test: %#v", results[2])
+	}
+}
+
+var outputTests = []Test{
+	{
+		Name: "TestWithLogs",
+		Fn: func(t *T) {
+			t.Log("output line 1")
+			t.Log("output line 2\noutput line 3")
+		},
+	},
+	{
+		Name: "TestNoLogs",
+		Fn:   func(t *T) {},
+	},
+	{
+		Name: "FailWithLogs",
+		Fn: func(t *T) {
+			t.Log("output line 1")
+			t.Error("failed 1")
+		},
+	},
+	{
+		Name: "FailMessage",
+		Fn: func(t *T) {
+			t.Error("failed 2")
+		},
+	},
+	{
+		Name: "FailNoOutput",
+		Fn: func(t *T) {
+			t.Fail()
+		},
+	},
+}
+
+func TestOutput(t *testing.T) {
+	t.Parallel()
+
+	var buf bytes.Buffer
+	RunTests(outputTests, &buf)
+
+	want := regexp.MustCompile(`
+^-- RUN TestWithLogs
+ output line 1
+ output line 2
+ output line 3
+-- OK TestWithLogs \([^)]+\)
+-- OK TestNoLogs \([^)]+\)
+-- RUN FailWithLogs
+ output line 1
+ failed 1
+-- FAIL FailWithLogs \([^)]+\)
+-- RUN FailMessage
+ failed 2
+-- FAIL FailMessage \([^)]+\)
+-- FAIL FailNoOutput \([^)]+\)
+2/5 tests passed.
+$`[1:])
+	if !want.MatchString(buf.String()) {
+		t.Fatalf("output does not match: %q", buf.String())
+	}
+}
+
+func TestOutputTAP(t *testing.T) {
+	t.Parallel()
+
+	var buf bytes.Buffer
+	RunTAP(outputTests, &buf)
+
+	want := `
+1..5
+ok 1 TestWithLogs
+# output line 1
+# output line 2
+# output line 3
+ok 2 TestNoLogs
+not ok 3 FailWithLogs
+# output line 1
+# failed 1
+not ok 4 FailMessage
+# failed 2
+not ok 5 FailNoOutput
+`
+	if buf.String() != want[1:] {
+		t.Fatalf("output does not match: %q", buf.String())
+	}
+}