path: root/libsolidity/analysis/SyntaxChecker.cpp

/*
    This file is part of solidity.

    solidity is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    solidity is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with solidity.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <libsolidity/analysis/SyntaxChecker.h>
#include <memory>
#include <libsolidity/ast/AST.h>
#include <libsolidity/analysis/SemVerHandler.h>
#include <libsolidity/interface/Version.h>

using namespace std;
using namespace dev;
using namespace dev::solidity;


bool SyntaxChecker::checkSyntax(ASTNode const& _astRoot)
{
    _astRoot.accept(*this);
    return Error::containsOnlyWarnings(m_errors);
}

void SyntaxChecker::warning(SourceLocation const& _location, string const& _description)
{
    auto err = make_shared<Error>(Error::Type::Warning);
    *err <<
        errinfo_sourceLocation(_location) <<
        errinfo_comment(_description);

    m_errors.push_back(err);
}

void SyntaxChecker::syntaxError(SourceLocation const& _location, std::string const& _description)
{
    auto err = make_shared<Error>(Error::Type::SyntaxError);
    *err <<
        errinfo_sourceLocation(_location) <<
        errinfo_comment(_description);

    m_errors.push_back(err);
}

bool SyntaxChecker::visit(SourceUnit const&)
{
    m_versionPragmaFound = false;
    return true;
}

void SyntaxChecker::endVisit(SourceUnit const& _sourceUnit)
{
    if (!m_versionPragmaFound)
    {
        string errorString("Source file does not specify required compiler version!");
        SemVerVersion recommendedVersion{string(VersionString)};
        if (!recommendedVersion.isPrerelease())
            errorString +=
                "Consider adding \"pragma solidity ^" +
                to_string(recommendedVersion.major()) +
                string(".") +
                to_string(recommendedVersion.minor()) +
                string(".") +
                to_string(recommendedVersion.patch());
                string(";\"");

        auto err = make_shared<Error>(Error::Type::Warning);
        *err <<
            errinfo_sourceLocation(_sourceUnit.location()) <<
            errinfo_comment(errorString);
        m_errors.push_back(err);
    }
}

bool SyntaxChecker::visit(PragmaDirective const& _pragma)
{
    solAssert(!_pragma.tokens().empty(), "");
    solAssert(_pragma.tokens().size() == _pragma.literals().size(), "");
    if (_pragma.tokens()[0] != Token::Identifier || _pragma.literals()[0] != "solidity")
        syntaxError(_pragma.location(), "Unknown pragma \"" + _pragma.literals()[0] + "\"");
    else
    {
        vector<Token::Value> tokens(_pragma.tokens().begin() + 1, _pragma.tokens().end());
        vector<string> literals(_pragma.literals().begin() + 1, _pragma.literals().end());
        SemVerMatchExpressionParser parser(tokens, literals);
        auto matchExpression = parser.parse();
        SemVerVersion currentVersion{string(VersionString)};
        if (!matchExpression.matches(currentVersion))
            syntaxError(
                _pragma.location(),
                "Source file requires different compiler version (current compiler is " +
                string(VersionString) + " - note that nightly builds are considered to be "
                "strictly less than the released version"
            );
        m_versionPragmaFound = true;
    }
    return true;
}

bool SyntaxChecker::visit(ModifierDefinition const&)
{
    m_placeholderFound = false;
    return true;
}

void SyntaxChecker::endVisit(ModifierDefinition const& _modifier)
{
    if (!m_placeholderFound)
        syntaxError(_modifier.body().location(), "Modifier body does not contain '_'.");
    m_placeholderFound = false;
}

bool SyntaxChecker::visit(WhileStatement const&)
{
    m_inLoopDepth++;
    return true;
}

void SyntaxChecker::endVisit(WhileStatement const&  )
{
    m_inLoopDepth--;
}

bool SyntaxChecker::visit(ForStatement const&)
{
    m_inLoopDepth++;
    return true;
}

void SyntaxChecker::endVisit(ForStatement const&)
{
    m_inLoopDepth--;
}

bool SyntaxChecker::visit(Continue const& _continueStatement)
{
    if (m_inLoopDepth <= 0)
        // we're not in a for/while loop, report syntax error
        syntaxError(_continueStatement.location(), "\"continue\" has to be in a \"for\" or \"while\" loop.");
    return true;
}

bool SyntaxChecker::visit(Break const& _breakStatement)
{
    if (m_inLoopDepth <= 0)
        // we're not in a for/while loop, report syntax error
        syntaxError(_breakStatement.location(), "\"break\" has to be in a \"for\" or \"while\" loop.");
    return true;
}

bool SyntaxChecker::visit(UnaryOperation const& _operation)
{
    if (_operation.getOperator() == Token::Add)
        warning(_operation.location(), "Use of unary + is deprecated.");
    return true;
}

bool SyntaxChecker::visit(PlaceholderStatement const&)
{
    m_placeholderFound = true;
    return true;
}