Merge pull request #269 from jupp0r/feature/improve-coverage

core: Improve test coverage

core/tests/CMakeLists.txt

@@ -1,5 +1,6 @@
 
 add_executable(prometheus_test
+  builder_test.cc
   check_names_test.cc
   counter_test.cc
   family_test.cc

core/tests/builder_test.cc

@@ -0,0 +1,96 @@
+#include "prometheus/counter.h"
+#include "prometheus/gauge.h"
+#include "prometheus/histogram.h"
+#include "prometheus/registry.h"
+#include "prometheus/summary.h"
+
+#include <gmock/gmock.h>
+#include <algorithm>
+
+namespace prometheus {
+namespace {
+
+class BuilderTest : public testing::Test {
+ protected:
+  std::vector<ClientMetric::Label> getExpectedLabels() {
+    std::vector<ClientMetric::Label> labels;
+
+    auto gen = [](std::pair<const std::string, std::string> p) {
+      return ClientMetric::Label{p.first, p.second};
+    };
+
+    std::transform(std::begin(const_labels), std::end(const_labels),
+                   std::back_inserter(labels), gen);
+    std::transform(std::begin(more_labels), std::end(more_labels),
+                   std::back_inserter(labels), gen);
+
+    return labels;
+  }
+
+  void verifyCollectedLabels() {
+    const auto collected = registry.Collect();
+
+    ASSERT_EQ(1U, collected.size());
+    EXPECT_EQ(name, collected.at(0).name);
+    EXPECT_EQ(help, collected.at(0).help);
+    ASSERT_EQ(1U, collected.at(0).metric.size());
+
+    EXPECT_THAT(collected.at(0).metric.at(0).label,
+                testing::UnorderedElementsAreArray(expected_labels));
+  }
+
+  Registry registry;
+
+  const std::string name = "some_name";
+  const std::string help = "Additional description.";
+  const std::map<std::string, std::string> const_labels = {{"key", "value"}};
+  const std::map<std::string, std::string> more_labels = {{"name", "test"}};
+  const std::vector<ClientMetric::Label> expected_labels = getExpectedLabels();
+};
+
+TEST_F(BuilderTest, build_counter) {
+  auto& family = BuildCounter()
+                     .Name(name)
+                     .Help(help)
+                     .Labels(const_labels)
+                     .Register(registry);
+  family.Add(more_labels);
+
+  verifyCollectedLabels();
+}
+
+TEST_F(BuilderTest, build_gauge) {
+  auto& family = BuildGauge()
+                     .Name(name)
+                     .Help(help)
+                     .Labels(const_labels)
+                     .Register(registry);
+  family.Add(more_labels);
+
+  verifyCollectedLabels();
+}
+
+TEST_F(BuilderTest, build_histogram) {
+  auto& family = BuildHistogram()
+                     .Name(name)
+                     .Help(help)
+                     .Labels(const_labels)
+                     .Register(registry);
+  family.Add(more_labels, Histogram::BucketBoundaries{1, 2});
+
+  verifyCollectedLabels();
+}
+
+TEST_F(BuilderTest, build_summary) {
+  auto& family = BuildSummary()
+                     .Name(name)
+                     .Help(help)
+                     .Labels(const_labels)
+                     .Register(registry);
+  family.Add(more_labels, Summary::Quantiles{});
+
+  verifyCollectedLabels();
+}
+
+}  // namespace
+}  // namespace prometheus

core/tests/gauge_test.cc

@@ -30,13 +30,27 @@ TEST(GaugeTest, inc_multiple) {
   EXPECT_EQ(gauge.Value(), 7.0);
 }
 
+TEST(GaugeTest, inc_negative_value) {
+  Gauge gauge;
+  gauge.Increment(5.0);
+  gauge.Increment(-5.0);
+  EXPECT_EQ(gauge.Value(), 5.0);
+}
+
 TEST(GaugeTest, dec) {
   Gauge gauge;
   gauge.Set(5.0);
   gauge.Decrement();
   EXPECT_EQ(gauge.Value(), 4.0);
 }
 
+TEST(GaugeTest, dec_negative_value) {
+  Gauge gauge;
+  gauge.Set(5.0);
+  gauge.Decrement(-1.0);
+  EXPECT_EQ(gauge.Value(), 5.0);
+}
+
 TEST(GaugeTest, dec_number) {
   Gauge gauge;
   gauge.Set(5.0);