//          Copyright Brian Schott (Sir Alaran) 2014.
// Distributed under the Boost Software License, Version 1.0.
//    (See accompanying file LICENSE_1_0.txt or copy at
//          http://www.boost.org/LICENSE_1_0.txt)

module analysis.ifelsesame;

import std.stdio;

import std.d.ast;
import std.d.lexer;
import analysis.base;
import analysis.helpers;


/**
 * Checks for if statements whose "then" block is the same as the "else" block
 */
class IfElseSameCheck : BaseAnalyzer
{
	alias visit = BaseAnalyzer.visit;

	this(string fileName)
	{
		super(fileName);
	}

	override void visit(const IfStatement ifStatement)
	{
		if (ifStatement.thenStatement == ifStatement.elseStatement)
			addErrorMessage(ifStatement.line, ifStatement.column,
				"'Else' branch is identical to 'Then' branch.");
		ifStatement.accept(this);
	}

	override void visit(const AssignExpression assignExpression)
	{
		const AssignExpression e = cast(const AssignExpression) assignExpression.assignExpression;
		if (e !is null && assignExpression.operator == tok!"="
			&& e.ternaryExpression == assignExpression.ternaryExpression)
		{
			addErrorMessage(assignExpression.line, assignExpression.column,
				"Left side of assignment operatior is identical to the right side.");
		}
		assignExpression.accept(this);
	}
}

unittest
{
	import analysis.config;
	StaticAnalysisConfig sac;
	sac.if_else_same_check = true;
	assertAnalyzerWarnings(q{
		void testSizeT()
		{
			string person = "unknown";
			if (person == "unknown") // [warn]: 'Else' branch is identical to 'Then' branch.
				person = "bobrick"; // same
			else
				person = "bobrick"; // same

			if (person == "unknown") // ok
				person = "ricky"; // not same
			else
				person = "bobby"; // not same
		}
	}c, sac);
	stderr.writeln("Unittest for IfElseSameCheck passed.");
}