tsdb: Improve TestFloatHistogramChunkAppendable and add new cases

Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>

tsdb/chunkenc/float_histogram_test.go

@@ -232,7 +232,7 @@ func TestFloatHistogramChunkAppendable(t *testing.T) {
 	require.Equal(t, 0, c.NumSamples())
 
 	ts := int64(1234567890)
-	h1 := &histogram.Histogram{
+	h1 := &histogram.FloatHistogram{
 		Count:         5,
 		ZeroCount:     2,
 		Sum:           18.4,
@@ -245,14 +245,29 @@ func TestFloatHistogramChunkAppendable(t *testing.T) {
 			{Offset: 3, Length: 1},
 			{Offset: 1, Length: 1},
 		},
-		PositiveBuckets: []int64{6, -3, 0, -1, 2, 1, -4}, // counts: 6, 3, 3, 2, 4, 5, 1 (total 24)
+		PositiveBuckets: []float64{6, 3, 3, 2, 4, 5, 1},
 	}
 
-	app.AppendFloatHistogram(ts, h1.ToFloat())
+	app.AppendFloatHistogram(ts, h1.Copy())
 	require.Equal(t, 1, c.NumSamples())
+	hApp, _ := app.(*FloatHistogramAppender)
+
+	{ // Schema change.
+		h2 := h1.Copy()
+		h2.Schema++
+		_, _, ok, _ := hApp.Appendable(h2)
+		require.False(t, ok)
+	}
+
+	{ // Zero threshold change.
+		h2 := h1.Copy()
+		h2.ZeroThreshold += 0.1
+		_, _, ok, _ := hApp.Appendable(h2)
+		require.False(t, ok)
+	}
 
 	{ // New histogram that has more buckets.
-		h2 := h1
+		h2 := h1.Copy()
 		h2.PositiveSpans = []histogram.Span{
 			{Offset: 0, Length: 3},
 			{Offset: 1, Length: 1},
@@ -262,13 +277,9 @@ func TestFloatHistogramChunkAppendable(t *testing.T) {
 		h2.Count += 9
 		h2.ZeroCount++
 		h2.Sum = 30
-		// Existing histogram should get values converted from the above to:
-		//   6 3 0 3 0 0 2 4 5 0 1 (previous values with some new empty buckets in between)
-		// so the new histogram should have new counts >= these per-bucket counts, e.g.:
-		h2.PositiveBuckets = []int64{7, -2, -4, 2, -2, -1, 2, 3, 0, -5, 1} // 7 5 1 3 1 0 2 5 5 0 1 (total 30)
+		h2.PositiveBuckets = []float64{7, 5, 1, 3, 1, 0, 2, 5, 5, 0, 1}
 
-		hApp, _ := app.(*FloatHistogramAppender)
-		posInterjections, negInterjections, ok, cr := hApp.Appendable(h2.ToFloat())
+		posInterjections, negInterjections, ok, cr := hApp.Appendable(h2)
 		require.Greater(t, len(posInterjections), 0)
 		require.Equal(t, 0, len(negInterjections))
 		require.True(t, ok) // Only new buckets came in.
@@ -276,7 +287,7 @@ func TestFloatHistogramChunkAppendable(t *testing.T) {
 	}
 
 	{ // New histogram that has a bucket missing.
-		h2 := h1
+		h2 := h1.Copy()
 		h2.PositiveSpans = []histogram.Span{
 			{Offset: 0, Length: 2},
 			{Offset: 5, Length: 2},
@@ -284,10 +295,9 @@ func TestFloatHistogramChunkAppendable(t *testing.T) {
 			{Offset: 1, Length: 1},
 		}
 		h2.Sum = 21
-		h2.PositiveBuckets = []int64{6, -3, -1, 2, 1, -4} // counts: 6, 3, 2, 4, 5, 1 (total 21)
+		h2.PositiveBuckets = []float64{6, 3, 2, 4, 5, 1}
 
-		hApp, _ := app.(*FloatHistogramAppender)
-		posInterjections, negInterjections, ok, cr := hApp.Appendable(h2.ToFloat())
+		posInterjections, negInterjections, ok, cr := hApp.Appendable(h2)
 		require.Equal(t, 0, len(posInterjections))
 		require.Equal(t, 0, len(negInterjections))
 		require.False(t, ok) // Need to cut a new chunk.
@@ -295,12 +305,11 @@ func TestFloatHistogramChunkAppendable(t *testing.T) {
 	}
 
 	{ // New histogram that has a counter reset while buckets are same.
-		h2 := h1
+		h2 := h1.Copy()
 		h2.Sum = 23
-		h2.PositiveBuckets = []int64{6, -4, 1, -1, 2, 1, -4} // counts: 6, 2, 3, 2, 4, 5, 1 (total 23)
+		h2.PositiveBuckets = []float64{6, 2, 3, 2, 4, 5, 1}
 
-		hApp, _ := app.(*FloatHistogramAppender)
-		posInterjections, negInterjections, ok, cr := hApp.Appendable(h2.ToFloat())
+		posInterjections, negInterjections, ok, cr := hApp.Appendable(h2)
 		require.Equal(t, 0, len(posInterjections))
 		require.Equal(t, 0, len(negInterjections))
 		require.False(t, ok) // Need to cut a new chunk.
@@ -308,7 +317,7 @@ func TestFloatHistogramChunkAppendable(t *testing.T) {
 	}
 
 	{ // New histogram that has a counter reset while new buckets were added.
-		h2 := h1
+		h2 := h1.Copy()
 		h2.PositiveSpans = []histogram.Span{
 			{Offset: 0, Length: 3},
 			{Offset: 1, Length: 1},
@@ -316,13 +325,9 @@ func TestFloatHistogramChunkAppendable(t *testing.T) {
 			{Offset: 3, Length: 3},
 		}
 		h2.Sum = 29
-		// Existing histogram should get values converted from the above to:
-		//   6 3 0 3 0 0 2 4 5 0 1 (previous values with some new empty buckets in between)
-		// so the new histogram should have new counts >= these per-bucket counts, e.g.:
-		h2.PositiveBuckets = []int64{7, -2, -4, 2, -2, -1, 2, 3, 0, -5, 0} // 7 5 1 3 1 0 2 5 5 0 0 (total 29)
+		h2.PositiveBuckets = []float64{7, 5, 1, 3, 1, 0, 2, 5, 5, 0, 0}
 
-		hApp, _ := app.(*FloatHistogramAppender)
-		posInterjections, negInterjections, ok, cr := hApp.Appendable(h2.ToFloat())
+		posInterjections, negInterjections, ok, cr := hApp.Appendable(h2)
 		require.Equal(t, 0, len(posInterjections))
 		require.Equal(t, 0, len(negInterjections))
 		require.False(t, ok) // Need to cut a new chunk.
@@ -334,7 +339,7 @@ func TestFloatHistogramChunkAppendable(t *testing.T) {
 		// added before the first bucket and reset on first bucket.  (to
 		// catch the edge case where the new bucket should be forwarded
 		// ahead until first old bucket at start)
-		h2 := h1
+		h2 := h1.Copy()
 		h2.PositiveSpans = []histogram.Span{
 			{Offset: -3, Length: 2},
 			{Offset: 1, Length: 2},
@@ -344,13 +349,9 @@ func TestFloatHistogramChunkAppendable(t *testing.T) {
 			{Offset: 1, Length: 1},
 		}
 		h2.Sum = 26
-		// Existing histogram should get values converted from the above to:
-		//   0, 0, 6, 3, 3, 2, 4, 5, 1
-		// so the new histogram should have new counts >= these per-bucket counts, e.g.:
-		h2.PositiveBuckets = []int64{1, 1, 3, -2, 0, -1, 2, 1, -4} // counts: 1, 2, 5, 3, 3, 2, 4, 5, 1 (total 26)
+		h2.PositiveBuckets = []float64{1, 2, 5, 3, 3, 2, 4, 5, 1}
 
-		hApp, _ := app.(*FloatHistogramAppender)
-		posInterjections, negInterjections, ok, cr := hApp.Appendable(h2.ToFloat())
+		posInterjections, negInterjections, ok, cr := hApp.Appendable(h2)
 		require.Equal(t, 0, len(posInterjections))
 		require.Equal(t, 0, len(negInterjections))
 		require.False(t, ok) // Need to cut a new chunk.