[hal, wpilibj] Add missing distance per pulse functions to EncoderSim (#4928)

Also fix C++ and Java EncoderSim.setDistancePerPulse() not propagating value to SimEncoderData.

wpilibj/src/main/java/edu/wpi/first/wpilibj/simulation/EncoderSim.java

@@ -303,6 +303,38 @@ public class EncoderSim {
     EncoderDataJNI.setSamplesToAverage(m_index, samplesToAverage);
   }
 
+  /**
+   * Register a callback on the distance per pulse value of this encoder.
+   *
+   * @param callback the callback that will be called whenever the distance per pulse is changed
+   * @param initialNotify if true, the callback will be run on the initial value
+   * @return the {@link CallbackStore} object associated with this callback. Save a reference to
+   *     this object so GC doesn't cancel the callback.
+   */
+  public CallbackStore registerDistancePerPulseCallback(
+      NotifyCallback callback, boolean initialNotify) {
+    int uid = EncoderDataJNI.registerDistancePerPulseCallback(m_index, callback, initialNotify);
+    return new CallbackStore(m_index, uid, EncoderDataJNI::cancelDistancePerPulseCallback);
+  }
+
+  /**
+   * Get the distance per pulse value.
+   *
+   * @return the distance per pulse value
+   */
+  public double getDistancePerPulse() {
+    return EncoderDataJNI.getDistancePerPulse(m_index);
+  }
+
+  /**
+   * Set the distance per pulse value.
+   *
+   * @param samplesToAverage the new value
+   */
+  public void setDistancePerPulse(double samplesToAverage) {
+    EncoderDataJNI.setDistancePerPulse(m_index, samplesToAverage);
+  }
+
   /**
    * Change the encoder distance.
    *

wpilibj/src/test/java/edu/wpi/first/wpilibj/simulation/EncoderSimTest.java

@@ -89,4 +89,23 @@ class EncoderSimTest {
       }
     }
   }
+
+  @Test
+  void testDistancePerPulse() {
+    HAL.initialize(500, 0);
+
+    try (Encoder encoder = new Encoder(0, 1)) {
+      EncoderSim sim = new EncoderSim(encoder);
+      sim.resetData();
+
+      DoubleCallback callback = new DoubleCallback();
+      try (CallbackStore cb = sim.registerDistancePerPulseCallback(callback, false)) {
+        sim.setDistancePerPulse(0.03405);
+        assertEquals(0.03405, sim.getDistancePerPulse());
+        assertEquals(0.03405, encoder.getDistancePerPulse());
+        assertTrue(callback.wasTriggered());
+        assertEquals(0.03405, callback.getSetValue());
+      }
+    }
+  }
 }