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

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//
//  Licensed to the Apache Software Foundation (ASF) under one or more
//  contributor license agreements.  See the NOTICE file distributed with
//  this work for additional information regarding copyright ownership.
//  The ASF licenses this file to You under the Apache License, Version 2.0
//  (the "License"); you may not use this file except in compliance with
//  the License.  You may obtain a copy of the License at
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//      http://www.apache.org/licenses/LICENSE-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.IExpressionNode;
import org.apache.royale.compiler.tree.as.IFunctionNode;
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;

/**
 * Check that a constructor does not specify a return type (not even `void`).
 */
public class NoConstructorReturnTypeRule extends LinterRule {
	@Override
	public Map<ASTNodeID, NodeVisitor> getNodeVisitors() {
		Map<ASTNodeID, NodeVisitor> result = new HashMap<>();
		result.put(ASTNodeID.FunctionID, (node, tokenQuery, problems) -> {
			checkFunctionNode((IFunctionNode) node, tokenQuery, problems);
		});
		return result;
	}

	private void checkFunctionNode(IFunctionNode functionNode, TokenQuery tokenQuery, Collection<ICompilerProblem> problems) {
		if (!functionNode.isConstructor()) {
			return;
		}
		IExpressionNode returnTypeNode = functionNode.getReturnTypeNode();
		if (returnTypeNode == null) {
			return;
		}
		problems.add(new NoConstructorReturnTypeLinterProblem(functionNode));
	}

	public static class NoConstructorReturnTypeLinterProblem extends CompilerProblem implements ILinterProblem {
		public static final String DESCRIPTION = "Constructor '${functionName}' must not specify '${returnType}' return type";

		public NoConstructorReturnTypeLinterProblem(IFunctionNode node)
		{
			super(node.getNameExpressionNode());
			functionName = node.getName();
			returnType = node.getReturnType();
		}

		public String functionName;
		public String returnType;
	}
}