adding merge test

Signed-off-by: alanprot <[email protected]>

Author: alanprot

Diff for: pkg/querier/stats/stats.go

@@ -225,14 +225,16 @@ func (s *QueryStats) AddNotOptimizedRegexMatchers(count uint64) {
 	if s == nil {
 		return
 	}
-	atomic.AddUint64(&s.NotOptimizedRegexCount, count)
+
+	// For this stats we get the MAX, instead of adding the counts
+	// as for split queries we will call this method multiples times.
+	atomic.StoreUint64(&s.NotOptimizedRegexCount, max(count, s.LoadNotOptimizedRegexMatchers()))
 }
 
 func (s *QueryStats) LoadNotOptimizedRegexMatchers() uint64 {
 	if s == nil {
 		return 0
 	}
-
 	return atomic.LoadUint64(&s.NotOptimizedRegexCount)
 }
 

Diff for: pkg/querier/stats/stats_test.go

@@ -221,6 +221,7 @@ func TestStats_Merge(t *testing.T) {
 		stats1.AddFetchedSamples(109)
 		stats1.AddScannedSamples(100)
 		stats1.AddPeakSamples(100)
+		stats1.AddNotOptimizedRegexMatchers(2)
 		stats1.AddExtraFields("a", "b")
 		stats1.AddExtraFields("a", "b")
 
@@ -234,6 +235,7 @@ func TestStats_Merge(t *testing.T) {
 		stats1.AddStoreGatewayTouchedPostingBytes(301)
 		stats2.AddFetchedChunks(102)
 		stats2.AddFetchedSamples(103)
+		stats2.AddNotOptimizedRegexMatchers(3)
 		stats2.AddPeakSamples(105)
 		stats2.AddScannedSamples(105)
 		stats2.AddExtraFields("c", "d")
@@ -251,6 +253,7 @@ func TestStats_Merge(t *testing.T) {
 		assert.Equal(t, uint64(105), stats1.LoadPeakSamples())
 		assert.Equal(t, uint64(401), stats1.LoadStoreGatewayTouchedPostings())
 		assert.Equal(t, uint64(601), stats1.LoadStoreGatewayTouchedPostingBytes())
+		assert.Equal(t, uint64(3), stats1.LoadNotOptimizedRegexMatchers())
 		checkExtraFields(t, []interface{}{"a", "b", "c", "d"}, stats1.LoadExtraFields())
 	})