linter/src/main/java/org/apache/royale/linter/rules/NoVoidOperatorRule.java

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//  this work for additional information regarding copyright ownership.
//  The ASF licenses this file to You under the Apache License, Version 2.0
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package org.apache.royale.linter.rules;

import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

import org.apache.royale.compiler.problems.CompilerProblem;
import org.apache.royale.compiler.problems.ICompilerProblem;
import org.apache.royale.compiler.tree.ASTNodeID;
import org.apache.royale.compiler.tree.as.IOperatorNode.OperatorType;
import org.apache.royale.compiler.tree.as.IUnaryOperatorNode;
import org.apache.royale.linter.LinterRule;
import org.apache.royale.linter.NodeVisitor;
import org.apache.royale.linter.TokenQuery;
import org.apache.royale.linter.problems.ILinterProblem;

/**
 * Checks for uses of 'void' operator. Using 'void' as return type is allowed.
 */
public class NoVoidOperatorRule extends LinterRule {
	@Override
	public Map<ASTNodeID, NodeVisitor> getNodeVisitors() {
		Map<ASTNodeID, NodeVisitor> result = new HashMap<>();
		result.put(ASTNodeID.Op_VoidID, (node, tokenQuery, problems) -> {
			checkUnaryOperatorNode((IUnaryOperatorNode) node, tokenQuery, problems);
		});
		return result;
	}

	private void checkUnaryOperatorNode(IUnaryOperatorNode unaryOperatorNode, TokenQuery tokenQuery,
			Collection<ICompilerProblem> problems) {
		if (!OperatorType.VOID.equals(unaryOperatorNode.getOperator())) {
			return;
		}
		problems.add(new NoVoidOperatorLinterProblem(unaryOperatorNode));
	}

	public static class NoVoidOperatorLinterProblem extends CompilerProblem implements ILinterProblem {
		public static final String DESCRIPTION = "Must not use 'void' operator";

		public NoVoidOperatorLinterProblem(IUnaryOperatorNode node)
		{
			super(node);
		}
	}
}