Fix -Werror=sign-compare warnings

Author: efernandez

fuse_models/test/test_imu_2d.cpp

@@ -148,8 +148,8 @@ TEST_F(Imu2DTestFixture, BaseFrameYawAngularVelocity)
   const auto added_variables = last_transaction.addedVariables();
   const auto added_constraints = last_transaction.addedConstraints();
 
-  ASSERT_EQ(5, boost::size(added_variables));
-  ASSERT_EQ(2, boost::size(added_constraints));
+  ASSERT_EQ(5u, boost::size(added_variables));
+  ASSERT_EQ(2u, boost::size(added_constraints));
 
   // With all constraints generated by the imu sensor model source
   for (const auto& constraint : added_constraints)
@@ -213,7 +213,7 @@ TEST_F(Imu2DTestFixture, BaseFrameYawAngularVelocity)
 
     // Check the angular velocity mean has a single value and it is the same as the wheel odometry one
     const auto& mean = velocity_angular->mean();
-    ASSERT_EQ(1, mean.size());
+    ASSERT_EQ(1u, mean.size());
     EXPECT_NEAR(w, mean[0], 1.0e-2);
   }
 
@@ -302,7 +302,7 @@ TEST_F(Imu2DTestFixture, BaseFrameYawAngularVelocity)
     const auto dt = position2->stamp().toSec() - position1->stamp().toSec();
     ASSERT_LT(0.0, dt);
 
-    ASSERT_EQ(3, delta.size());
+    ASSERT_EQ(3u, delta.size());
     EXPECT_NEAR(w, delta[2] / dt, 1.0e-2);
   }
 }