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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-16 19:23:18 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-16 19:23:18 +0000
commit43a123c1ae6613b3efeed291fa552ecd909d3acf (patch)
treefd92518b7024bc74031f78a1cf9e454b65e73665 /src/testing/sub_test.go
parentInitial commit. (diff)
downloadgolang-1.20-upstream.tar.xz
golang-1.20-upstream.zip
Adding upstream version 1.20.14.upstream/1.20.14upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/testing/sub_test.go')
-rw-r--r--src/testing/sub_test.go1004
1 files changed, 1004 insertions, 0 deletions
diff --git a/src/testing/sub_test.go b/src/testing/sub_test.go
new file mode 100644
index 0000000..55b14c3
--- /dev/null
+++ b/src/testing/sub_test.go
@@ -0,0 +1,1004 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package testing
+
+import (
+ "bytes"
+ "fmt"
+ "reflect"
+ "regexp"
+ "runtime"
+ "strings"
+ "sync"
+ "sync/atomic"
+ "time"
+)
+
+func init() {
+ // Make benchmark tests run 10x faster.
+ benchTime.d = 100 * time.Millisecond
+}
+
+func TestTestContext(t *T) {
+ const (
+ add1 = 0
+ done = 1
+ )
+ // After each of the calls are applied to the context, the
+ type call struct {
+ typ int // run or done
+ // result from applying the call
+ running int
+ waiting int
+ started bool
+ }
+ testCases := []struct {
+ max int
+ run []call
+ }{{
+ max: 1,
+ run: []call{
+ {typ: add1, running: 1, waiting: 0, started: true},
+ {typ: done, running: 0, waiting: 0, started: false},
+ },
+ }, {
+ max: 1,
+ run: []call{
+ {typ: add1, running: 1, waiting: 0, started: true},
+ {typ: add1, running: 1, waiting: 1, started: false},
+ {typ: done, running: 1, waiting: 0, started: true},
+ {typ: done, running: 0, waiting: 0, started: false},
+ {typ: add1, running: 1, waiting: 0, started: true},
+ },
+ }, {
+ max: 3,
+ run: []call{
+ {typ: add1, running: 1, waiting: 0, started: true},
+ {typ: add1, running: 2, waiting: 0, started: true},
+ {typ: add1, running: 3, waiting: 0, started: true},
+ {typ: add1, running: 3, waiting: 1, started: false},
+ {typ: add1, running: 3, waiting: 2, started: false},
+ {typ: add1, running: 3, waiting: 3, started: false},
+ {typ: done, running: 3, waiting: 2, started: true},
+ {typ: add1, running: 3, waiting: 3, started: false},
+ {typ: done, running: 3, waiting: 2, started: true},
+ {typ: done, running: 3, waiting: 1, started: true},
+ {typ: done, running: 3, waiting: 0, started: true},
+ {typ: done, running: 2, waiting: 0, started: false},
+ {typ: done, running: 1, waiting: 0, started: false},
+ {typ: done, running: 0, waiting: 0, started: false},
+ },
+ }}
+ for i, tc := range testCases {
+ ctx := &testContext{
+ startParallel: make(chan bool),
+ maxParallel: tc.max,
+ }
+ for j, call := range tc.run {
+ doCall := func(f func()) chan bool {
+ done := make(chan bool)
+ go func() {
+ f()
+ done <- true
+ }()
+ return done
+ }
+ started := false
+ switch call.typ {
+ case add1:
+ signal := doCall(ctx.waitParallel)
+ select {
+ case <-signal:
+ started = true
+ case ctx.startParallel <- true:
+ <-signal
+ }
+ case done:
+ signal := doCall(ctx.release)
+ select {
+ case <-signal:
+ case <-ctx.startParallel:
+ started = true
+ <-signal
+ }
+ }
+ if started != call.started {
+ t.Errorf("%d:%d:started: got %v; want %v", i, j, started, call.started)
+ }
+ if ctx.running != call.running {
+ t.Errorf("%d:%d:running: got %v; want %v", i, j, ctx.running, call.running)
+ }
+ if ctx.numWaiting != call.waiting {
+ t.Errorf("%d:%d:waiting: got %v; want %v", i, j, ctx.numWaiting, call.waiting)
+ }
+ }
+ }
+}
+
+func TestTRun(t *T) {
+ realTest := t
+ testCases := []struct {
+ desc string
+ ok bool
+ maxPar int
+ chatty bool
+ json bool
+ output string
+ f func(*T)
+ }{{
+ desc: "failnow skips future sequential and parallel tests at same level",
+ ok: false,
+ maxPar: 1,
+ output: `
+--- FAIL: failnow skips future sequential and parallel tests at same level (N.NNs)
+ --- FAIL: failnow skips future sequential and parallel tests at same level/#00 (N.NNs)
+ `,
+ f: func(t *T) {
+ ranSeq := false
+ ranPar := false
+ t.Run("", func(t *T) {
+ t.Run("par", func(t *T) {
+ t.Parallel()
+ ranPar = true
+ })
+ t.Run("seq", func(t *T) {
+ ranSeq = true
+ })
+ t.FailNow()
+ t.Run("seq", func(t *T) {
+ realTest.Error("test must be skipped")
+ })
+ t.Run("par", func(t *T) {
+ t.Parallel()
+ realTest.Error("test must be skipped.")
+ })
+ })
+ if !ranPar {
+ realTest.Error("parallel test was not run")
+ }
+ if !ranSeq {
+ realTest.Error("sequential test was not run")
+ }
+ },
+ }, {
+ desc: "failure in parallel test propagates upwards",
+ ok: false,
+ maxPar: 1,
+ output: `
+--- FAIL: failure in parallel test propagates upwards (N.NNs)
+ --- FAIL: failure in parallel test propagates upwards/#00 (N.NNs)
+ --- FAIL: failure in parallel test propagates upwards/#00/par (N.NNs)
+ `,
+ f: func(t *T) {
+ t.Run("", func(t *T) {
+ t.Parallel()
+ t.Run("par", func(t *T) {
+ t.Parallel()
+ t.Fail()
+ })
+ })
+ },
+ }, {
+ desc: "skipping without message, chatty",
+ ok: true,
+ chatty: true,
+ output: `
+=== RUN skipping without message, chatty
+--- SKIP: skipping without message, chatty (N.NNs)`,
+ f: func(t *T) { t.SkipNow() },
+ }, {
+ desc: "chatty with recursion",
+ ok: true,
+ chatty: true,
+ output: `
+=== RUN chatty with recursion
+=== RUN chatty with recursion/#00
+=== RUN chatty with recursion/#00/#00
+--- PASS: chatty with recursion (N.NNs)
+ --- PASS: chatty with recursion/#00 (N.NNs)
+ --- PASS: chatty with recursion/#00/#00 (N.NNs)`,
+ f: func(t *T) {
+ t.Run("", func(t *T) {
+ t.Run("", func(t *T) {})
+ })
+ },
+ }, {
+ desc: "chatty with recursion and json",
+ ok: false,
+ chatty: true,
+ json: true,
+ output: `
+^V=== RUN chatty with recursion and json
+^V=== RUN chatty with recursion and json/#00
+^V=== RUN chatty with recursion and json/#00/#00
+^V--- PASS: chatty with recursion and json/#00/#00 (N.NNs)
+^V=== NAME chatty with recursion and json/#00
+^V=== RUN chatty with recursion and json/#00/#01
+ sub_test.go:NNN: skip
+^V--- SKIP: chatty with recursion and json/#00/#01 (N.NNs)
+^V=== NAME chatty with recursion and json/#00
+^V=== RUN chatty with recursion and json/#00/#02
+ sub_test.go:NNN: fail
+^V--- FAIL: chatty with recursion and json/#00/#02 (N.NNs)
+^V=== NAME chatty with recursion and json/#00
+^V--- FAIL: chatty with recursion and json/#00 (N.NNs)
+^V=== NAME chatty with recursion and json
+^V--- FAIL: chatty with recursion and json (N.NNs)
+^V=== NAME `,
+ f: func(t *T) {
+ t.Run("", func(t *T) {
+ t.Run("", func(t *T) {})
+ t.Run("", func(t *T) { t.Skip("skip") })
+ t.Run("", func(t *T) { t.Fatal("fail") })
+ })
+ },
+ }, {
+ desc: "skipping without message, not chatty",
+ ok: true,
+ f: func(t *T) { t.SkipNow() },
+ }, {
+ desc: "skipping after error",
+ output: `
+--- FAIL: skipping after error (N.NNs)
+ sub_test.go:NNN: an error
+ sub_test.go:NNN: skipped`,
+ f: func(t *T) {
+ t.Error("an error")
+ t.Skip("skipped")
+ },
+ }, {
+ desc: "use Run to locally synchronize parallelism",
+ ok: true,
+ maxPar: 1,
+ f: func(t *T) {
+ var count uint32
+ t.Run("waitGroup", func(t *T) {
+ for i := 0; i < 4; i++ {
+ t.Run("par", func(t *T) {
+ t.Parallel()
+ atomic.AddUint32(&count, 1)
+ })
+ }
+ })
+ if count != 4 {
+ t.Errorf("count was %d; want 4", count)
+ }
+ },
+ }, {
+ desc: "alternate sequential and parallel",
+ // Sequential tests should partake in the counting of running threads.
+ // Otherwise, if one runs parallel subtests in sequential tests that are
+ // itself subtests of parallel tests, the counts can get askew.
+ ok: true,
+ maxPar: 1,
+ f: func(t *T) {
+ t.Run("a", func(t *T) {
+ t.Parallel()
+ t.Run("b", func(t *T) {
+ // Sequential: ensure running count is decremented.
+ t.Run("c", func(t *T) {
+ t.Parallel()
+ })
+
+ })
+ })
+ },
+ }, {
+ desc: "alternate sequential and parallel 2",
+ // Sequential tests should partake in the counting of running threads.
+ // Otherwise, if one runs parallel subtests in sequential tests that are
+ // itself subtests of parallel tests, the counts can get askew.
+ ok: true,
+ maxPar: 2,
+ f: func(t *T) {
+ for i := 0; i < 2; i++ {
+ t.Run("a", func(t *T) {
+ t.Parallel()
+ time.Sleep(time.Nanosecond)
+ for i := 0; i < 2; i++ {
+ t.Run("b", func(t *T) {
+ time.Sleep(time.Nanosecond)
+ for i := 0; i < 2; i++ {
+ t.Run("c", func(t *T) {
+ t.Parallel()
+ time.Sleep(time.Nanosecond)
+ })
+ }
+
+ })
+ }
+ })
+ }
+ },
+ }, {
+ desc: "stress test",
+ ok: true,
+ maxPar: 4,
+ f: func(t *T) {
+ t.Parallel()
+ for i := 0; i < 12; i++ {
+ t.Run("a", func(t *T) {
+ t.Parallel()
+ time.Sleep(time.Nanosecond)
+ for i := 0; i < 12; i++ {
+ t.Run("b", func(t *T) {
+ time.Sleep(time.Nanosecond)
+ for i := 0; i < 12; i++ {
+ t.Run("c", func(t *T) {
+ t.Parallel()
+ time.Sleep(time.Nanosecond)
+ t.Run("d1", func(t *T) {})
+ t.Run("d2", func(t *T) {})
+ t.Run("d3", func(t *T) {})
+ t.Run("d4", func(t *T) {})
+ })
+ }
+ })
+ }
+ })
+ }
+ },
+ }, {
+ desc: "skip output",
+ ok: true,
+ maxPar: 4,
+ f: func(t *T) {
+ t.Skip()
+ },
+ }, {
+ desc: "subtest calls error on parent",
+ ok: false,
+ output: `
+--- FAIL: subtest calls error on parent (N.NNs)
+ sub_test.go:NNN: first this
+ sub_test.go:NNN: and now this!
+ sub_test.go:NNN: oh, and this too`,
+ maxPar: 1,
+ f: func(t *T) {
+ t.Errorf("first this")
+ outer := t
+ t.Run("", func(t *T) {
+ outer.Errorf("and now this!")
+ })
+ t.Errorf("oh, and this too")
+ },
+ }, {
+ desc: "subtest calls fatal on parent",
+ ok: false,
+ output: `
+--- FAIL: subtest calls fatal on parent (N.NNs)
+ sub_test.go:NNN: first this
+ sub_test.go:NNN: and now this!
+ --- FAIL: subtest calls fatal on parent/#00 (N.NNs)
+ testing.go:NNN: test executed panic(nil) or runtime.Goexit: subtest may have called FailNow on a parent test`,
+ maxPar: 1,
+ f: func(t *T) {
+ outer := t
+ t.Errorf("first this")
+ t.Run("", func(t *T) {
+ outer.Fatalf("and now this!")
+ })
+ t.Errorf("Should not reach here.")
+ },
+ }, {
+ desc: "subtest calls error on ancestor",
+ ok: false,
+ output: `
+--- FAIL: subtest calls error on ancestor (N.NNs)
+ sub_test.go:NNN: Report to ancestor
+ --- FAIL: subtest calls error on ancestor/#00 (N.NNs)
+ sub_test.go:NNN: Still do this
+ sub_test.go:NNN: Also do this`,
+ maxPar: 1,
+ f: func(t *T) {
+ outer := t
+ t.Run("", func(t *T) {
+ t.Run("", func(t *T) {
+ outer.Errorf("Report to ancestor")
+ })
+ t.Errorf("Still do this")
+ })
+ t.Errorf("Also do this")
+ },
+ }, {
+ desc: "subtest calls fatal on ancestor",
+ ok: false,
+ output: `
+--- FAIL: subtest calls fatal on ancestor (N.NNs)
+ sub_test.go:NNN: Nope`,
+ maxPar: 1,
+ f: func(t *T) {
+ outer := t
+ t.Run("", func(t *T) {
+ for i := 0; i < 4; i++ {
+ t.Run("", func(t *T) {
+ outer.Fatalf("Nope")
+ })
+ t.Errorf("Don't do this")
+ }
+ t.Errorf("And neither do this")
+ })
+ t.Errorf("Nor this")
+ },
+ }, {
+ desc: "panic on goroutine fail after test exit",
+ ok: false,
+ maxPar: 4,
+ f: func(t *T) {
+ ch := make(chan bool)
+ t.Run("", func(t *T) {
+ go func() {
+ <-ch
+ defer func() {
+ if r := recover(); r == nil {
+ realTest.Errorf("expected panic")
+ }
+ ch <- true
+ }()
+ t.Errorf("failed after success")
+ }()
+ })
+ ch <- true
+ <-ch
+ },
+ }, {
+ desc: "log in finished sub test logs to parent",
+ ok: false,
+ output: `
+ --- FAIL: log in finished sub test logs to parent (N.NNs)
+ sub_test.go:NNN: message2
+ sub_test.go:NNN: message1
+ sub_test.go:NNN: error`,
+ maxPar: 1,
+ f: func(t *T) {
+ ch := make(chan bool)
+ t.Run("sub", func(t2 *T) {
+ go func() {
+ <-ch
+ t2.Log("message1")
+ ch <- true
+ }()
+ })
+ t.Log("message2")
+ ch <- true
+ <-ch
+ t.Errorf("error")
+ },
+ }, {
+ // A chatty test should always log with fmt.Print, even if the
+ // parent test has completed.
+ desc: "log in finished sub test with chatty",
+ ok: false,
+ chatty: true,
+ output: `
+ --- FAIL: log in finished sub test with chatty (N.NNs)`,
+ maxPar: 1,
+ f: func(t *T) {
+ ch := make(chan bool)
+ t.Run("sub", func(t2 *T) {
+ go func() {
+ <-ch
+ t2.Log("message1")
+ ch <- true
+ }()
+ })
+ t.Log("message2")
+ ch <- true
+ <-ch
+ t.Errorf("error")
+ },
+ }, {
+ // If a subtest panics we should run cleanups.
+ desc: "cleanup when subtest panics",
+ ok: false,
+ chatty: false,
+ output: `
+--- FAIL: cleanup when subtest panics (N.NNs)
+ --- FAIL: cleanup when subtest panics/sub (N.NNs)
+ sub_test.go:NNN: running cleanup`,
+ f: func(t *T) {
+ t.Cleanup(func() { t.Log("running cleanup") })
+ t.Run("sub", func(t2 *T) {
+ t2.FailNow()
+ })
+ },
+ }}
+ for _, tc := range testCases {
+ t.Run(tc.desc, func(t *T) {
+ ctx := newTestContext(tc.maxPar, allMatcher())
+ buf := &strings.Builder{}
+ root := &T{
+ common: common{
+ signal: make(chan bool),
+ barrier: make(chan bool),
+ name: "",
+ w: buf,
+ },
+ context: ctx,
+ }
+ if tc.chatty {
+ root.chatty = newChattyPrinter(root.w)
+ root.chatty.json = tc.json
+ }
+ ok := root.Run(tc.desc, tc.f)
+ ctx.release()
+
+ if ok != tc.ok {
+ t.Errorf("%s:ok: got %v; want %v", tc.desc, ok, tc.ok)
+ }
+ if ok != !root.Failed() {
+ t.Errorf("%s:root failed: got %v; want %v", tc.desc, !ok, root.Failed())
+ }
+ if ctx.running != 0 || ctx.numWaiting != 0 {
+ t.Errorf("%s:running and waiting non-zero: got %d and %d", tc.desc, ctx.running, ctx.numWaiting)
+ }
+ got := strings.TrimSpace(buf.String())
+ want := strings.TrimSpace(tc.output)
+ re := makeRegexp(want)
+ if ok, err := regexp.MatchString(re, got); !ok || err != nil {
+ t.Errorf("%s:output:\ngot:\n%s\nwant:\n%s", tc.desc, got, want)
+ }
+ })
+ }
+}
+
+func TestBRun(t *T) {
+ work := func(b *B) {
+ for i := 0; i < b.N; i++ {
+ time.Sleep(time.Nanosecond)
+ }
+ }
+ testCases := []struct {
+ desc string
+ failed bool
+ chatty bool
+ output string
+ f func(*B)
+ }{{
+ desc: "simulate sequential run of subbenchmarks.",
+ f: func(b *B) {
+ b.Run("", func(b *B) { work(b) })
+ time1 := b.result.NsPerOp()
+ b.Run("", func(b *B) { work(b) })
+ time2 := b.result.NsPerOp()
+ if time1 >= time2 {
+ t.Errorf("no time spent in benchmark t1 >= t2 (%d >= %d)", time1, time2)
+ }
+ },
+ }, {
+ desc: "bytes set by all benchmarks",
+ f: func(b *B) {
+ b.Run("", func(b *B) { b.SetBytes(10); work(b) })
+ b.Run("", func(b *B) { b.SetBytes(10); work(b) })
+ if b.result.Bytes != 20 {
+ t.Errorf("bytes: got: %d; want 20", b.result.Bytes)
+ }
+ },
+ }, {
+ desc: "bytes set by some benchmarks",
+ // In this case the bytes result is meaningless, so it must be 0.
+ f: func(b *B) {
+ b.Run("", func(b *B) { b.SetBytes(10); work(b) })
+ b.Run("", func(b *B) { work(b) })
+ b.Run("", func(b *B) { b.SetBytes(10); work(b) })
+ if b.result.Bytes != 0 {
+ t.Errorf("bytes: got: %d; want 0", b.result.Bytes)
+ }
+ },
+ }, {
+ desc: "failure carried over to root",
+ failed: true,
+ output: "--- FAIL: root",
+ f: func(b *B) { b.Fail() },
+ }, {
+ desc: "skipping without message, chatty",
+ chatty: true,
+ output: "--- SKIP: root",
+ f: func(b *B) { b.SkipNow() },
+ }, {
+ desc: "chatty with recursion",
+ chatty: true,
+ f: func(b *B) {
+ b.Run("", func(b *B) {
+ b.Run("", func(b *B) {})
+ })
+ },
+ }, {
+ desc: "skipping without message, not chatty",
+ f: func(b *B) { b.SkipNow() },
+ }, {
+ desc: "skipping after error",
+ failed: true,
+ output: `
+--- FAIL: root
+ sub_test.go:NNN: an error
+ sub_test.go:NNN: skipped`,
+ f: func(b *B) {
+ b.Error("an error")
+ b.Skip("skipped")
+ },
+ }, {
+ desc: "memory allocation",
+ f: func(b *B) {
+ const bufSize = 256
+ alloc := func(b *B) {
+ var buf [bufSize]byte
+ for i := 0; i < b.N; i++ {
+ _ = append([]byte(nil), buf[:]...)
+ }
+ }
+ b.Run("", func(b *B) {
+ alloc(b)
+ b.ReportAllocs()
+ })
+ b.Run("", func(b *B) {
+ alloc(b)
+ b.ReportAllocs()
+ })
+ // runtime.MemStats sometimes reports more allocations than the
+ // benchmark is responsible for. Luckily the point of this test is
+ // to ensure that the results are not underreported, so we can
+ // simply verify the lower bound.
+ if got := b.result.MemAllocs; got < 2 {
+ t.Errorf("MemAllocs was %v; want 2", got)
+ }
+ if got := b.result.MemBytes; got < 2*bufSize {
+ t.Errorf("MemBytes was %v; want %v", got, 2*bufSize)
+ }
+ },
+ }, {
+ desc: "cleanup is called",
+ f: func(b *B) {
+ var calls, cleanups, innerCalls, innerCleanups int
+ b.Run("", func(b *B) {
+ calls++
+ b.Cleanup(func() {
+ cleanups++
+ })
+ b.Run("", func(b *B) {
+ b.Cleanup(func() {
+ innerCleanups++
+ })
+ innerCalls++
+ })
+ work(b)
+ })
+ if calls == 0 || calls != cleanups {
+ t.Errorf("mismatched cleanups; got %d want %d", cleanups, calls)
+ }
+ if innerCalls == 0 || innerCalls != innerCleanups {
+ t.Errorf("mismatched cleanups; got %d want %d", cleanups, calls)
+ }
+ },
+ }, {
+ desc: "cleanup is called on failure",
+ failed: true,
+ f: func(b *B) {
+ var calls, cleanups int
+ b.Run("", func(b *B) {
+ calls++
+ b.Cleanup(func() {
+ cleanups++
+ })
+ b.Fatalf("failure")
+ })
+ if calls == 0 || calls != cleanups {
+ t.Errorf("mismatched cleanups; got %d want %d", cleanups, calls)
+ }
+ },
+ }}
+ hideStdoutForTesting = true
+ defer func() {
+ hideStdoutForTesting = false
+ }()
+ for _, tc := range testCases {
+ t.Run(tc.desc, func(t *T) {
+ var ok bool
+ buf := &strings.Builder{}
+ // This is almost like the Benchmark function, except that we override
+ // the benchtime and catch the failure result of the subbenchmark.
+ root := &B{
+ common: common{
+ signal: make(chan bool),
+ name: "root",
+ w: buf,
+ },
+ benchFunc: func(b *B) { ok = b.Run("test", tc.f) }, // Use Run to catch failure.
+ benchTime: durationOrCountFlag{d: 1 * time.Microsecond},
+ }
+ if tc.chatty {
+ root.chatty = newChattyPrinter(root.w)
+ }
+ root.runN(1)
+ if ok != !tc.failed {
+ t.Errorf("%s:ok: got %v; want %v", tc.desc, ok, !tc.failed)
+ }
+ if !ok != root.Failed() {
+ t.Errorf("%s:root failed: got %v; want %v", tc.desc, !ok, root.Failed())
+ }
+ // All tests are run as subtests
+ if root.result.N != 1 {
+ t.Errorf("%s: N for parent benchmark was %d; want 1", tc.desc, root.result.N)
+ }
+ got := strings.TrimSpace(buf.String())
+ want := strings.TrimSpace(tc.output)
+ re := makeRegexp(want)
+ if ok, err := regexp.MatchString(re, got); !ok || err != nil {
+ t.Errorf("%s:output:\ngot:\n%s\nwant:\n%s", tc.desc, got, want)
+ }
+ })
+ }
+}
+
+func makeRegexp(s string) string {
+ s = regexp.QuoteMeta(s)
+ s = strings.ReplaceAll(s, "^V", "\x16")
+ s = strings.ReplaceAll(s, ":NNN:", `:\d\d\d\d?:`)
+ s = strings.ReplaceAll(s, "N\\.NNs", `\d*\.\d*s`)
+ return s
+}
+
+func TestBenchmarkOutput(t *T) {
+ // Ensure Benchmark initialized common.w by invoking it with an error and
+ // normal case.
+ Benchmark(func(b *B) { b.Error("do not print this output") })
+ Benchmark(func(b *B) {})
+}
+
+func TestBenchmarkStartsFrom1(t *T) {
+ var first = true
+ Benchmark(func(b *B) {
+ if first && b.N != 1 {
+ panic(fmt.Sprintf("Benchmark() first N=%v; want 1", b.N))
+ }
+ first = false
+ })
+}
+
+func TestBenchmarkReadMemStatsBeforeFirstRun(t *T) {
+ var first = true
+ Benchmark(func(b *B) {
+ if first && (b.startAllocs == 0 || b.startBytes == 0) {
+ panic("ReadMemStats not called before first run")
+ }
+ first = false
+ })
+}
+
+func TestParallelSub(t *T) {
+ c := make(chan int)
+ block := make(chan int)
+ for i := 0; i < 10; i++ {
+ go func(i int) {
+ <-block
+ t.Run(fmt.Sprint(i), func(t *T) {})
+ c <- 1
+ }(i)
+ }
+ close(block)
+ for i := 0; i < 10; i++ {
+ <-c
+ }
+}
+
+type funcWriter struct {
+ write func([]byte) (int, error)
+}
+
+func (fw *funcWriter) Write(b []byte) (int, error) {
+ return fw.write(b)
+}
+
+func TestRacyOutput(t *T) {
+ var runs int32 // The number of running Writes
+ var races int32 // Incremented for each race detected
+ raceDetector := func(b []byte) (int, error) {
+ // Check if some other goroutine is concurrently calling Write.
+ if atomic.LoadInt32(&runs) > 0 {
+ atomic.AddInt32(&races, 1) // Race detected!
+ }
+ atomic.AddInt32(&runs, 1)
+ defer atomic.AddInt32(&runs, -1)
+ runtime.Gosched() // Increase probability of a race
+ return len(b), nil
+ }
+
+ root := &T{
+ common: common{w: &funcWriter{raceDetector}},
+ context: newTestContext(1, allMatcher()),
+ }
+ root.chatty = newChattyPrinter(root.w)
+ root.Run("", func(t *T) {
+ var wg sync.WaitGroup
+ for i := 0; i < 100; i++ {
+ wg.Add(1)
+ go func(i int) {
+ defer wg.Done()
+ t.Run(fmt.Sprint(i), func(t *T) {
+ t.Logf("testing run %d", i)
+ })
+ }(i)
+ }
+ wg.Wait()
+ })
+
+ if races > 0 {
+ t.Errorf("detected %d racy Writes", races)
+ }
+}
+
+// The late log message did not include the test name. Issue 29388.
+func TestLogAfterComplete(t *T) {
+ ctx := newTestContext(1, allMatcher())
+ var buf bytes.Buffer
+ t1 := &T{
+ common: common{
+ // Use a buffered channel so that tRunner can write
+ // to it although nothing is reading from it.
+ signal: make(chan bool, 1),
+ w: &buf,
+ },
+ context: ctx,
+ }
+
+ c1 := make(chan bool)
+ c2 := make(chan string)
+ tRunner(t1, func(t *T) {
+ t.Run("TestLateLog", func(t *T) {
+ go func() {
+ defer close(c2)
+ defer func() {
+ p := recover()
+ if p == nil {
+ c2 <- "subtest did not panic"
+ return
+ }
+ s, ok := p.(string)
+ if !ok {
+ c2 <- fmt.Sprintf("subtest panic with unexpected value %v", p)
+ return
+ }
+ const want = "Log in goroutine after TestLateLog has completed: log after test"
+ if !strings.Contains(s, want) {
+ c2 <- fmt.Sprintf("subtest panic %q does not contain %q", s, want)
+ }
+ }()
+
+ <-c1
+ t.Log("log after test")
+ }()
+ })
+ })
+ close(c1)
+
+ if s := <-c2; s != "" {
+ t.Error(s)
+ }
+}
+
+func TestBenchmark(t *T) {
+ if Short() {
+ t.Skip("skipping in short mode")
+ }
+ res := Benchmark(func(b *B) {
+ for i := 0; i < 5; i++ {
+ b.Run("", func(b *B) {
+ for i := 0; i < b.N; i++ {
+ time.Sleep(time.Millisecond)
+ }
+ })
+ }
+ })
+ if res.NsPerOp() < 4000000 {
+ t.Errorf("want >5ms; got %v", time.Duration(res.NsPerOp()))
+ }
+}
+
+func TestCleanup(t *T) {
+ var cleanups []int
+ t.Run("test", func(t *T) {
+ t.Cleanup(func() { cleanups = append(cleanups, 1) })
+ t.Cleanup(func() { cleanups = append(cleanups, 2) })
+ })
+ if got, want := cleanups, []int{2, 1}; !reflect.DeepEqual(got, want) {
+ t.Errorf("unexpected cleanup record; got %v want %v", got, want)
+ }
+}
+
+func TestConcurrentCleanup(t *T) {
+ cleanups := 0
+ t.Run("test", func(t *T) {
+ done := make(chan struct{})
+ for i := 0; i < 2; i++ {
+ i := i
+ go func() {
+ t.Cleanup(func() {
+ cleanups |= 1 << i
+ })
+ done <- struct{}{}
+ }()
+ }
+ <-done
+ <-done
+ })
+ if cleanups != 1|2 {
+ t.Errorf("unexpected cleanup; got %d want 3", cleanups)
+ }
+}
+
+func TestCleanupCalledEvenAfterGoexit(t *T) {
+ cleanups := 0
+ t.Run("test", func(t *T) {
+ t.Cleanup(func() {
+ cleanups++
+ })
+ t.Cleanup(func() {
+ runtime.Goexit()
+ })
+ })
+ if cleanups != 1 {
+ t.Errorf("unexpected cleanup count; got %d want 1", cleanups)
+ }
+}
+
+func TestRunCleanup(t *T) {
+ outerCleanup := 0
+ innerCleanup := 0
+ t.Run("test", func(t *T) {
+ t.Cleanup(func() { outerCleanup++ })
+ t.Run("x", func(t *T) {
+ t.Cleanup(func() { innerCleanup++ })
+ })
+ })
+ if innerCleanup != 1 {
+ t.Errorf("unexpected inner cleanup count; got %d want 1", innerCleanup)
+ }
+ if outerCleanup != 1 {
+ t.Errorf("unexpected outer cleanup count; got %d want 0", outerCleanup)
+ }
+}
+
+func TestCleanupParallelSubtests(t *T) {
+ ranCleanup := 0
+ t.Run("test", func(t *T) {
+ t.Cleanup(func() { ranCleanup++ })
+ t.Run("x", func(t *T) {
+ t.Parallel()
+ if ranCleanup > 0 {
+ t.Error("outer cleanup ran before parallel subtest")
+ }
+ })
+ })
+ if ranCleanup != 1 {
+ t.Errorf("unexpected cleanup count; got %d want 1", ranCleanup)
+ }
+}
+
+func TestNestedCleanup(t *T) {
+ ranCleanup := 0
+ t.Run("test", func(t *T) {
+ t.Cleanup(func() {
+ if ranCleanup != 2 {
+ t.Errorf("unexpected cleanup count in first cleanup: got %d want 2", ranCleanup)
+ }
+ ranCleanup++
+ })
+ t.Cleanup(func() {
+ if ranCleanup != 0 {
+ t.Errorf("unexpected cleanup count in second cleanup: got %d want 0", ranCleanup)
+ }
+ ranCleanup++
+ t.Cleanup(func() {
+ if ranCleanup != 1 {
+ t.Errorf("unexpected cleanup count in nested cleanup: got %d want 1", ranCleanup)
+ }
+ ranCleanup++
+ })
+ })
+ })
+ if ranCleanup != 3 {
+ t.Errorf("unexpected cleanup count: got %d want 3", ranCleanup)
+ }
+}