execution/filter: allow multiple matchers with same name (#320)

It is entirely valid to have multiple matchers with the same name e.g.
`phase!="Running", phase!="Succeeded`.

See #312.

Signed-off-by: Giedrius Statkevičius <[email protected]>

execution/storage/filter.go

@@ -21,17 +21,17 @@ func (n nopFilter) Matches(storage.Series) bool { return true }
 
 type filter struct {
 	matchers   []*labels.Matcher
-	matcherSet map[string]*labels.Matcher
+	matcherSet map[string][]*labels.Matcher
 }
 
 func NewFilter(matchers []*labels.Matcher) Filter {
 	if len(matchers) == 0 {
 		return &nopFilter{}
 	}
 
-	matcherSet := make(map[string]*labels.Matcher)
+	matcherSet := make(map[string][]*labels.Matcher)
 	for _, m := range matchers {
-		matcherSet[m.Name] = m
+		matcherSet[m.Name] = append(matcherSet[m.Name], m)
 	}
 	return &filter{
 		matchers:   matchers,
@@ -46,10 +46,13 @@ func (f filter) Matches(series storage.Series) bool {
 		return true
 	}
 
-	for name, m := range f.matcherSet {
+	for name, matchers := range f.matcherSet {
 		label := series.Labels().Get(name)
-		if !m.Matches(label) {
-			return false
+
+		for _, m := range matchers {
+			if !m.Matches(label) {
+				return false
+			}
 		}
 	}
 

execution/storage/filter_test.go

@@ -9,10 +9,20 @@ import (
 	"github.com/prometheus/prometheus/model/labels"
 	promstg "github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/tsdb/chunkenc"
+	"github.com/stretchr/testify/require"
 
 	"github.com/thanos-io/promql-engine/execution/storage"
 )
 
+func TestFilter_MultipleMatcherWithSameName(t *testing.T) {
+	f := storage.NewFilter([]*labels.Matcher{
+		labels.MustNewMatcher(labels.MatchNotEqual, "phase", "Running"),
+		labels.MustNewMatcher(labels.MatchNotEqual, "phase", "Succeeded"),
+	})
+
+	require.Equal(t, false, f.Matches(&mockLabelSeries{labels: labels.FromStrings("phase", "Running")}))
+}
+
 func TestFilter_Matches(t *testing.T) {
 	testCases := []struct {
 		name     string