From b1b0750e5b587f85e3197985c3a206cc8ded1053 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Juraj=20Or=C5=A1uli=C4=87?= <juraj.orsulic@fer.hr>
Date: Wed, 4 Oct 2017 13:15:35 +0200
Subject: [PATCH] Check ratios in fixed rate sampler. (#502)

---
 cartographer/common/fixed_ratio_sampler.cc      | 7 ++++++-
 cartographer/common/fixed_ratio_sampler_test.cc | 9 ++++-----
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/cartographer/common/fixed_ratio_sampler.cc b/cartographer/common/fixed_ratio_sampler.cc
index 7de8c77..5f466a1 100644
--- a/cartographer/common/fixed_ratio_sampler.cc
+++ b/cartographer/common/fixed_ratio_sampler.cc
@@ -16,10 +16,15 @@
 
 #include "cartographer/common/fixed_ratio_sampler.h"
 
+#include "glog/logging.h"
+
 namespace cartographer {
 namespace common {
 
-FixedRatioSampler::FixedRatioSampler(const double ratio) : ratio_(ratio) {}
+FixedRatioSampler::FixedRatioSampler(const double ratio) : ratio_(ratio) {
+  CHECK_GT(ratio, 0.);
+  CHECK_LE(ratio, 1.);
+}
 
 FixedRatioSampler::~FixedRatioSampler() {}
 
diff --git a/cartographer/common/fixed_ratio_sampler_test.cc b/cartographer/common/fixed_ratio_sampler_test.cc
index 3bce575..fdcfdc5 100644
--- a/cartographer/common/fixed_ratio_sampler_test.cc
+++ b/cartographer/common/fixed_ratio_sampler_test.cc
@@ -29,11 +29,10 @@ TEST(FixedRatioSamplerTest, AlwaysTrue) {
   }
 }
 
-TEST(FixedRatioSamplerTest, AlwaysFalse) {
-  FixedRatioSampler fixed_ratio_sampler(0.);
-  for (int i = 0; i < 100; ++i) {
-    EXPECT_FALSE(fixed_ratio_sampler.Pulse());
-  }
+TEST(FixedRatioSamplerTest, NonSensicalRatio) {
+  EXPECT_DEATH(FixedRatioSampler(0.), "ratio");
+  EXPECT_DEATH(FixedRatioSampler(2.), "ratio");
+  EXPECT_DEATH(FixedRatioSampler(-0.1), "ratio");
 }
 
 TEST(FixedRatioSamplerTest, SometimesTrue) {