Handle Nil State Object (#5575)

* handle panic
* Merge branch 'master' into handlePanic
* Merge refs/heads/master into handlePanic
* Merge refs/heads/master into handlePanic

beacon-chain/state/getters.go

@@ -126,7 +126,7 @@ func (b *BeaconState) CloneInnerState() *pbp2p.BeaconState {
 // HasInnerState detects if the internal reference to the state data structure
 // is populated correctly. Returns false if nil.
 func (b *BeaconState) HasInnerState() bool {
-	return b.state != nil
+	return b != nil && b.state != nil
 }
 
 // GenesisTime of the beacon state as a uint64.

beacon-chain/state/getters_test.go

@@ -28,3 +28,15 @@ func TestBeaconState_SlotDataRace(t *testing.T) {
 
 	wg.Wait()
 }
+
+func TestNilState_NoPanic(t *testing.T) {
+	var st *BeaconState
+	defer func() {
+		if r := recover(); r != nil {
+			t.Errorf("Method panicked when it was not supposed to: %v", r)
+		}
+	}()
+	// retrieve elements from nil state
+	_ = st.GenesisValidatorRoot()
+	_ = st.Eth1Data()
+}