Add comments to test cases

Author: ViktorCVS

control_toolbox/test/pid_tests.cpp

@@ -469,51 +469,62 @@ TEST(CommandTest, integralOnlyTest)
 
   // If initial error = 0, i-gain = 1, dt = 1
   cmd = pid.compute_command(-0.5, 1.0);
-  // Then expect command = 0.0, since the integral contribution is calculated
-  // with backwards Euler (i.e. it is calculated after the command is computed)
+  // Then expect command = -0.5
   EXPECT_EQ(-0.5, cmd);
 
   // If call again with same arguments
   cmd = pid.compute_command(-0.5, 1.0);
+  // Then expect command = -1 (-0.5+(-0.5))
   EXPECT_EQ(-1.0, cmd);
 
   // Call again with no error
   cmd = pid.compute_command(0.0, 1.0);
+  // Then expect command = -1 (-1+0)
   EXPECT_EQ(-1.0, cmd);
 
   // Double check that the integral contribution keep the previous command
   cmd = pid.compute_command(0.0, 1.0);
+  // Then expect command = -1 (-1+0)
   EXPECT_EQ(-1.0, cmd);
 
   // Finally call again with positive error to see if the command changes in the opposite direction
   cmd = pid.compute_command(1.0, 1.0);
+  // Then expect command = 0 (-1+1)
   EXPECT_EQ(0.0, cmd);
 
-  // If initial error = 0, i-gain = 1, dt = 1
-  cmd = pid.compute_command(0.0, 1.0);
-  EXPECT_EQ(0.0, cmd);
+  cmd = pid.compute_command(-0.5, 1.0);
+  // Then expect command = -0.5 (0+(-0.5))
+  EXPECT_EQ(-0.5, cmd);
+
   // after reset without argument (save_i_term=false)
   // we expect the command to be 0 if update is called error = 0
   pid.reset();
   cmd = pid.compute_command(0.0, 1.0);
+  // Then expect command = 0
   EXPECT_EQ(0.0, cmd);
 
   // If initial error = 0, i-gain = 1, dt = 1
   cmd = pid.compute_command(-0.5, 1.0);
+  // Then expect command = -0.5
   EXPECT_EQ(-0.5, cmd);
+
   // after reset with argument (save_i_term=false)
   // we expect the command to be 0 if update is called error = 0
   pid.reset(false);
-  cmd = pid.compute_command(-0.5, 1.0);
-  EXPECT_EQ(-0.5, cmd);
+  cmd = pid.compute_command(0.0, 1.0);
+  // Then expect command = 0.0 since it was reset
+  EXPECT_EQ(0.0, cmd);
 
   // If initial error = 0, i-gain = 1, dt = 1
-  cmd = pid.compute_command(0.0, 1.0);
+  cmd = pid.compute_command(-0.5, 1.0);
+  // Then expect command = -0.5 (-0.5+0)
   EXPECT_EQ(-0.5, cmd);
+
   // after reset with save_i_term=true
   // we expect still the same command if update is called error = 0
   pid.reset(true);
   cmd = pid.compute_command(0.0, 1.0);
+  // Then expect command = -0.5 since reset was called with save_i_term=true
   EXPECT_EQ(-0.5, cmd);
 }