v0.4.1

internal/rrd/rrd_test.go

@@ -0,0 +1,56 @@
+package rrd
+
+import "testing"
+
+func f(v float64) *float64 { return &v }
+
+func TestDownsampleNoop(t *testing.T) {
+	in := []Point{{T: 1, V: f(1)}, {T: 2, V: f(2)}, {T: 3, V: f(3)}}
+	out := downsample(in, 10)
+	if len(out) != len(in) {
+		t.Fatalf("expected no-op for points <= target, got %d points", len(out))
+	}
+}
+
+func TestDownsampleAveragesBuckets(t *testing.T) {
+	// 10 points, 0..9, bucketed down to 5: expect roughly paired averages.
+	in := make([]Point, 10)
+	for i := range in {
+		in[i] = Point{T: int64(i), V: f(float64(i))}
+	}
+	out := downsample(in, 5)
+	if len(out) != 5 {
+		t.Fatalf("expected 5 points, got %d", len(out))
+	}
+	want := []float64{0.5, 2.5, 4.5, 6.5, 8.5}
+	for i, pt := range out {
+		if pt.V == nil {
+			t.Fatalf("bucket %d: expected a value, got nil", i)
+		}
+		if *pt.V != want[i] {
+			t.Errorf("bucket %d: got %v, want %v", i, *pt.V, want[i])
+		}
+	}
+}
+
+func TestDownsampleSkipsNulls(t *testing.T) {
+	in := []Point{{T: 1, V: f(2)}, {T: 2, V: nil}, {T: 3, V: f(4)}, {T: 4, V: nil}}
+	out := downsample(in, 1)
+	if len(out) != 1 {
+		t.Fatalf("expected 1 bucket, got %d", len(out))
+	}
+	if out[0].V == nil || *out[0].V != 3 {
+		t.Fatalf("expected average of non-null values (3), got %v", out[0].V)
+	}
+}
+
+func TestDownsampleAllNullBucketStaysNull(t *testing.T) {
+	in := []Point{{T: 1, V: nil}, {T: 2, V: nil}}
+	out := downsample(in, 1)
+	if len(out) != 1 {
+		t.Fatalf("expected 1 bucket, got %d", len(out))
+	}
+	if out[0].V != nil {
+		t.Fatalf("expected nil for an all-null bucket, got %v", *out[0].V)
+	}
+}