test: improve coverage

core/tests/histogram_test.cc

@@ -57,6 +57,11 @@ TEST(HistogramTest, reject_unsorted_bucket_bounds) {
   EXPECT_ANY_THROW(Histogram({2, 1}));
 }
 
+TEST(HistogramTest, reject_unsorted_bucket_bounds_lvalue) {
+  const Histogram::BucketBoundaries unsorted = {2, 1};
+  EXPECT_THROW(Histogram{unsorted}, std::invalid_argument);
+}
+
 TEST(HistogramTest, reject_non_incrementing_bucket_bounds) {
   EXPECT_ANY_THROW(Histogram({1, 2, 2, 3}));
 }

core/tests/summary_test.cc

@@ -102,5 +102,26 @@ TEST(SummaryTest, construction_with_dynamic_quantile_vector) {
   summary.Observe(8.0);
 }
 
+TEST(SummaryTest, quantile_with_out_of_order_batches) {
+  // Flush large values into the sample first, then insert smaller values so
+  // that insertBatch() hits the --idx path (value < sample_[item].value).
+  Summary summary{Summary::Quantiles{{0.5, 0.05}}, std::chrono::hours{1}};
+
+  for (int i = 0; i < 10; ++i) summary.Observe(100.0 + i);
+  summary.Collect();  // flushes buffer → sample_ now contains large values
+
+  for (int i = 0; i < 10; ++i) summary.Observe(1.0 + i);
+  auto metric = summary.Collect();  // flushes buffer with small values < existing sample → --idx
+  auto s = metric.summary;
+
+  // 20 observations total, sum = (1..10) + (100..109) = 55 + 1045 = 1100
+  EXPECT_EQ(s.sample_count, 20U);
+  EXPECT_DOUBLE_EQ(s.sample_sum, 1100.0);
+  // p50 with error 0.05 on 20 samples: rank error ≤ 1, true median is 10 or 100
+  ASSERT_EQ(s.quantile.size(), 1U);
+  EXPECT_GE(s.quantile.at(0).value, 1.0);
+  EXPECT_LE(s.quantile.at(0).value, 109.0);
+}
+
 }  // namespace
 }  // namespace prometheus

pull/tests/integration/integration_test.cc

@@ -274,6 +274,19 @@ TEST_F(BasicAuthIntegrationTest, shouldRejectWrongAuthorizationMethod) {
 }
 #endif
 
+TEST_F(BasicAuthIntegrationTest, shouldRejectNonBasicAuthScheme) {
+  std::unique_ptr<curl_slist, decltype(&curl_slist_free_all)> header(
+      curl_slist_append(nullptr, "Authorization: Bearer sometoken"),
+      curl_slist_free_all);
+
+  fetchPrePerform_ = [&header](CURL* curl) {
+    curl_easy_setopt(curl, CURLOPT_HTTPHEADER, header.get());
+  };
+
+  const auto metrics = FetchMetrics(default_metrics_path_);
+  ASSERT_EQ(metrics.code, 401);
+}
+
 TEST_F(BasicAuthIntegrationTest, shouldRejectMalformedBase64) {
   std::unique_ptr<curl_slist, decltype(&curl_slist_free_all)> header(
       curl_slist_append(nullptr, "Authorization: Basic $"),

push/tests/internal/label_encoder_test.cc

@@ -23,6 +23,18 @@ TEST_F(LabelEncoderTest, regular) {
   EXPECT_EQ("/foo/bar", Encode(Label{"foo", "bar"}));
 }
 
+TEST_F(LabelEncoderTest, uppercase) {
+  EXPECT_EQ("/foo/Bar", Encode(Label{"foo", "Bar"}));
+}
+
+TEST_F(LabelEncoderTest, digits) {
+  EXPECT_EQ("/foo/bar123", Encode(Label{"foo", "bar123"}));
+}
+
+TEST_F(LabelEncoderTest, unreserved_chars) {
+  EXPECT_EQ("/foo/a-b.c_d~e", Encode(Label{"foo", "a-b.c_d~e"}));
+}
+
 TEST_F(LabelEncoderTest, empty) {
   EXPECT_EQ("/first_label@base64/=", Encode(Label{"first_label", ""}));
 }

util/tests/unit/base64_test.cc

@@ -36,6 +36,9 @@ const TestVector testVector[] = {
     {"easure.", "ZWFzdXJlLg=="},
     {"asure.", "YXN1cmUu"},
     {"sure.", "c3VyZS4="},
+
+    // '/' character in encoded output (covers temp |= 0x3F branch in decode)
+    {"\xff\xff\xff", "////"},
 };
 
 using namespace testing;