[dev.fuzz] testing: let -fuzztime specify a number of executions

-fuzztime now works similarly to -benchtime: if it's given a string
with an "x" suffix (as opposed to "s" or some other unit of
duration), the fuzzing system will generate and run a maximum number
of values.

This CL also implements tracking and printing counts, since most of
the work was already done.

Change-Id: I013007984b5adfc1a751c379dc98c8d46b4a97e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/306909
Trust: Jay Conrod <jayconrod@google.com>
Trust: Katie Hockman <katie@golang.org>
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Katie Hockman <katie@golang.org>

1 files changed, 7 insertions, 7 deletions

diff --git a/src/testing/benchmark.go b/src/testing/benchmark.go
index a8f75e9712..ac22ac5b26 100644
--- a/src/testing/benchmark.go
+++ b/src/testing/benchmark.go
@@ -32,35 +32,35 @@ var (
 	matchBenchmarks *string
 	benchmarkMemory *bool
 
-	benchTime = benchTimeFlag{d: 1 * time.Second} // changed during test of testing package
+	benchTime = durationOrCountFlag{d: 1 * time.Second} // changed during test of testing package
 )
 
-type benchTimeFlag struct {
+type durationOrCountFlag struct {
 	d time.Duration
 	n int
 }
 
-func (f *benchTimeFlag) String() string {
+func (f *durationOrCountFlag) String() string {
 	if f.n > 0 {
 		return fmt.Sprintf("%dx", f.n)
 	}
 	return time.Duration(f.d).String()
 }
 
-func (f *benchTimeFlag) Set(s string) error {
+func (f *durationOrCountFlag) Set(s string) error {
 	if strings.HasSuffix(s, "x") {
 		n, err := strconv.ParseInt(s[:len(s)-1], 10, 0)
 		if err != nil || n <= 0 {
 			return fmt.Errorf("invalid count")
 		}
-		*f = benchTimeFlag{n: int(n)}
+		*f = durationOrCountFlag{n: int(n)}
 		return nil
 	}
 	d, err := time.ParseDuration(s)
 	if err != nil || d <= 0 {
 		return fmt.Errorf("invalid duration")
 	}
-	*f = benchTimeFlag{d: d}
+	*f = durationOrCountFlag{d: d}
 	return nil
 }
 
@@ -98,7 +98,7 @@ type B struct {
 	previousN        int           // number of iterations in the previous run
 	previousDuration time.Duration // total duration of the previous run
 	benchFunc        func(b *B)
-	benchTime        benchTimeFlag
+	benchTime        durationOrCountFlag
 	bytes            int64
 	missingBytes     bool // one of the subbenchmarks does not have bytes set.
 	timerOn          bool