Files
fejkdata/internal/drawstate/drawstate_test.go
T

54 lines
1.3 KiB
Go

package drawstate
import "testing"
func TestOneSeedDrawsOneSequence(t *testing.T) {
a, b := New(42), New(42)
for i := 0; i < 50; i++ {
if x, y := a.IntN(1<<30), b.IntN(1<<30); x != y {
t.Fatalf("seed 42 diverged at draw %d: %d != %d", i, x, y)
}
}
}
func TestTwoSeedsDrawTwoSequences(t *testing.T) {
a, b := New(1), New(2)
for i := 0; i < 50; i++ {
if a.IntN(1<<30) != b.IntN(1<<30) {
return
}
}
t.Fatal("seeds 1 and 2 drew identical sequences")
}
func TestCountersCountFromOneEach(t *testing.T) {
s := New(1)
for want := uint64(1); want <= 3; want++ {
if got := s.Seq(""); got != want {
t.Fatalf("Seq(\"\") = %d, want %d", got, want)
}
}
if got := s.Seq("orders"); got != 1 {
t.Fatalf("Seq(orders) = %d, want its own count from 1", got)
}
if got := s.Seq(""); got != 4 {
t.Fatalf("Seq(\"\") after Seq(orders) = %d, want 4", got)
}
if got := New(1).Seq(""); got != 1 {
t.Fatalf("a new state's Seq = %d, want 1", got)
}
}
func TestWeightedDrawsByWeight(t *testing.T) {
s := New(1)
counts := make([]int, 3)
for i := 0; i < 30000; i++ {
counts[s.Weighted([]float64{1, 2, 6})]++
}
for i, want := range []float64{1.0 / 6, 1.0 / 6, 4.0 / 6} {
if share := float64(counts[i]) / 30000; share < want-0.02 || share > want+0.02 {
t.Errorf("index %d drew a share of %.3f, want about %.3f", i, share, want)
}
}
}