Add indexes scans metric tests

Author: diogonicoleti

gauges/gauge_test.go

@@ -95,7 +95,7 @@ func connect(t *testing.T) *sql.DB {
 }
 
 func createTestTable(t *testing.T, db *sql.DB) func() {
-	_, err := db.Exec("CREATE TABLE IF NOT EXISTS testtable(id bigint)")
+	_, err := db.Exec("CREATE TABLE IF NOT EXISTS testtable(id bigint PRIMARY KEY)")
 	require.NoError(t, err)
 	return func() {
 		_, err := db.Exec("DROP TABLE IF EXISTS testtable")

gauges/indexes_test.go

@@ -6,6 +6,19 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
+func TestIndexesScans(t *testing.T) {
+	var assert = assert.New(t)
+	db, gauges, close := prepare(t)
+	defer close()
+	dropTestTable := createTestTable(t, db)
+	defer dropTestTable()
+
+	var metrics = evaluate(t, gauges.IndexesScans())
+	assert.Len(metrics, 1)
+	assertEqual(t, 0, metrics[0])
+	assertNoErrs(t, gauges)
+}
+
 func TestUnusedIndexes(t *testing.T) {
 	var assert = assert.New(t)
 	_, gauges, close := prepare(t)

gauges/table_sizes_test.go

@@ -16,7 +16,7 @@ func TestTableSizes(t *testing.T) {
 	var metrics = evaluate(t, gauges.TableSizes())
 	assert.Len(metrics, 3)
 	for _, metric := range metrics {
-		assertEqual(t, 0, metric)
+		assertGreaterThan(t, -1, metric)
 	}
 	assertNoErrs(t, gauges)
 }