/*
* Copyright (c) 2014 Patrick Scheibe
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package de.halirutan.mathematica.parsing.psi.util;
import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiFile;
import com.intellij.psi.util.PsiElementFilter;
import de.halirutan.mathematica.parsing.psi.api.Symbol;
import de.halirutan.mathematica.parsing.psi.api.assignment.Set;
import de.halirutan.mathematica.parsing.psi.api.assignment.SetDelayed;
import java.util.List;
/**
* @author patrick (1/6/14)
*/
public class UnreferencedSymbolFilter implements PsiElementFilter {
public static final int MAX_UPWARD_STEPS = 3;
@Override
public boolean isAccepted(PsiElement element) {
if (element instanceof Symbol) {
Symbol symbol = (Symbol) element;
PsiElement parent = symbol.getParent();
int iter = 0;
while (parent != null && ++iter != MAX_UPWARD_STEPS && !(parent instanceof PsiFile)) {
if (parent instanceof Set || parent instanceof SetDelayed) {
final List<Symbol> assignmentSymbols = MathematicaPsiUtilities.getAssignmentSymbols(parent);
return assignmentSymbols != null && assignmentSymbols.contains(element);
}
parent = parent.getParent();
}
}
return false;
}
}