strconv: add tests for issue 2917
Cannot reproduce the failure locally,
but add explicit test in case some other
machine can.
Fixes #2917 (for now).
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5651071
diff --git a/src/pkg/strconv/atof_test.go b/src/pkg/strconv/atof_test.go
index 72cea49..1da8c84 100644
--- a/src/pkg/strconv/atof_test.go
+++ b/src/pkg/strconv/atof_test.go
@@ -226,6 +226,40 @@
t.Logf("tested %d random numbers", len(atofRandomTests))
}
+var roundTripCases = []struct {
+ f float64
+ s string
+}{
+ // Issue 2917.
+ // A Darwin/386 builder failed on AtofRandom with this case.
+ {8865794286000691 << 39, "4.87402195346389e+27"},
+ {8865794286000692 << 39, "4.8740219534638903e+27"},
+}
+
+func TestRoundTrip(t *testing.T) {
+ for _, tt := range roundTripCases {
+ old := SetOptimize(false)
+ s := FormatFloat(tt.f, 'g', -1, 64)
+ if s != tt.s {
+ t.Errorf("no-opt FormatFloat(%b) = %s, want %s", tt.f, s, tt.s)
+ }
+ f, err := ParseFloat(tt.s, 64)
+ if f != tt.f || err != nil {
+ t.Errorf("no-opt ParseFloat(%s) = %b, %v want %b, nil", tt.s, f, err, tt.f)
+ }
+ SetOptimize(true)
+ s = FormatFloat(tt.f, 'g', -1, 64)
+ if s != tt.s {
+ t.Errorf("opt FormatFloat(%b) = %s, want %s", tt.f, s, tt.s)
+ }
+ f, err = ParseFloat(tt.s, 64)
+ if f != tt.f || err != nil {
+ t.Errorf("opt ParseFloat(%s) = %b, %v want %b, nil", tt.s, f, err, tt.f)
+ }
+ SetOptimize(old)
+ }
+}
+
func BenchmarkAtof64Decimal(b *testing.B) {
for i := 0; i < b.N; i++ {
ParseFloat("33909", 64)
