fw: fix pit test

PIT entries once removed cannot be reused, even for removing. Since
remove is only called from the priority queue expiration function,
this should not be a problem.

fw/table/pit-cs-tree.go

@@ -198,6 +198,7 @@ func (p *PitCsTree) InsertInterest(interest ndn.Interest, hint enc.Name, inFace
 
 // RemoveInterest removes the specified PIT entry, returning true if the entry
 // was removed and false if was not (because it does not exist).
+// The pitEntry should NEVER be used again after this call.
 func (p *PitCsTree) RemoveInterest(pitEntry PitEntry) bool {
 	e := pitEntry.(*nameTreePitEntry) // No error check needed because PitCsTree always uses nameTreePitEntry
 	for i, entry := range e.node.pitEntries {

fw/table/pit-cs-tree_test.go

@@ -262,14 +262,12 @@ func TestRemoveInterest(t *testing.T) {
 	assert.True(t, removedInterest)
 	assert.Equal(t, pitCS.PitSize(), 0)
 
-	// Remove a nonexistent pit entry
+	// Remove a new pit entry
 	name2, _ := enc.NameFromStr("/interest2")
 	interest2 := makeInterest(name2)
 	pitEntry2, _ := pitCS.InsertInterest(interest2, hint, inFace)
-
-	removedInterest = pitCS.RemoveInterest(pitEntry)
-	assert.False(t, removedInterest)
 	assert.Equal(t, pitCS.PitSize(), 1)
+
 	removedInterest = pitCS.RemoveInterest(pitEntry2)
 	assert.True(t, removedInterest)
 	assert.Equal(t, pitCS.PitSize(), 0)