Add tests for retrieving fingerprints for label matchers.

This checks for the basic behaviour of GetFingerprintsForLabelMatchers, that is, whether the different matcher types filter the correct fingerprints and intersections are correct.

storage/local/storage_test.go

@@ -30,7 +30,114 @@ import (
 )
 
 func TestGetFingerprintsForLabelMatchers(t *testing.T) {
+	storage, closer := NewTestStorage(t)
+	defer closer.Close()
+
+	samples := make([]*clientmodel.Sample, 100)
+	fingerprints := make(clientmodel.Fingerprints, 100)
+
+	for i := range samples {
+		metric := clientmodel.Metric{
+			clientmodel.MetricNameLabel: clientmodel.LabelValue(fmt.Sprintf("test_metric_%d", i)),
+			"label1":                    clientmodel.LabelValue(fmt.Sprintf("test_%d", i/10)),
+			"label2":                    clientmodel.LabelValue(fmt.Sprintf("test_%d", (i+5)/10)),
+		}
+		samples[i] = &clientmodel.Sample{
+			Metric:    metric,
+			Timestamp: clientmodel.Timestamp(i),
+			Value:     clientmodel.SampleValue(i),
+		}
+		fingerprints[i] = metric.Fingerprint()
+	}
 
+	storage.AppendSamples(samples)
+	storage.WaitForIndexing()
+
+	newMatcher := func(matchType metric.MatchType, name clientmodel.LabelName, value clientmodel.LabelValue) *metric.LabelMatcher {
+		lm, err := metric.NewLabelMatcher(matchType, name, value)
+		if err != nil {
+			t.Fatalf("error creating label matcher: %s", err)
+		}
+		return lm
+	}
+
+	var matcherTests = []struct {
+		matchers metric.LabelMatchers
+		expected clientmodel.Fingerprints
+	}{
+		{
+			matchers: metric.LabelMatchers{newMatcher(metric.Equal, "label1", "x")},
+			expected: fingerprints[:0],
+		},
+		{
+			matchers: metric.LabelMatchers{newMatcher(metric.Equal, "label1", "test_0")},
+			expected: fingerprints[:10],
+		},
+		{
+			matchers: metric.LabelMatchers{
+				newMatcher(metric.Equal, "label1", "test_0"),
+				newMatcher(metric.Equal, "label2", "test_1"),
+			},
+			expected: fingerprints[5:10],
+		},
+		{
+			matchers: metric.LabelMatchers{newMatcher(metric.NotEqual, "label1", "x")},
+			expected: fingerprints,
+		},
+		{
+			matchers: metric.LabelMatchers{newMatcher(metric.NotEqual, "label1", "test_0")},
+			expected: fingerprints[10:],
+		},
+		{
+			matchers: metric.LabelMatchers{
+				newMatcher(metric.NotEqual, "label1", "test_0"),
+				newMatcher(metric.NotEqual, "label1", "test_1"),
+				newMatcher(metric.NotEqual, "label1", "test_2"),
+			},
+			expected: fingerprints[30:],
+		},
+		{
+			matchers: metric.LabelMatchers{newMatcher(metric.RegexMatch, "label1", `test_[3-5]`)},
+			expected: fingerprints[30:60],
+		},
+		{
+			matchers: metric.LabelMatchers{newMatcher(metric.RegexNoMatch, "label1", `test_[3-5]`)},
+			expected: append(append(clientmodel.Fingerprints{}, fingerprints[:30]...), fingerprints[60:]...),
+		},
+		{
+			matchers: metric.LabelMatchers{
+				newMatcher(metric.RegexMatch, "label1", `test_[3-5]`),
+				newMatcher(metric.RegexMatch, "label2", `test_[4-6]`),
+			},
+			expected: fingerprints[35:60],
+		},
+		{
+			matchers: metric.LabelMatchers{
+				newMatcher(metric.RegexMatch, "label1", `test_[3-5]`),
+				newMatcher(metric.NotEqual, "label2", `test_4`),
+			},
+			expected: append(append(clientmodel.Fingerprints{}, fingerprints[30:35]...), fingerprints[45:60]...),
+		},
+	}
+
+	for _, mt := range matcherTests {
+		resfps := storage.GetFingerprintsForLabelMatchers(mt.matchers)
+		if len(mt.expected) != len(resfps) {
+			t.Fatalf("expected %d matches for %q, found %d", len(mt.expected), mt.matchers, len(resfps))
+		}
+		for _, fp1 := range resfps {
+			found := false
+			for _, fp2 := range mt.expected {
+				if fp1 == fp2 {
+					found = true
+					break
+				}
+			}
+			if !found {
+				t.Errorf("expected fingerprint %s for %q not in result", fp1, mt.matchers)
+			}
+		}
+	}
 }
 
 // TestLoop is just a smoke test for the loop method, if we can switch it on and