/*
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/>.
*/
// SPDX-License-Identifier: GPL-3.0
/**
* @author Christian <c@ethdev.com>
* @date 2014
* Solidity parser.
*/
#pragma once
#include <libsolidity/ast/AST.h>
#include <liblangutil/ParserBase.h>
#include <liblangutil/EVMVersion.h>
namespace solidity::langutil
{
class Scanner;
}
namespace solidity::frontend
{
class Parser: public langutil::ParserBase
{
public:
explicit Parser(
langutil::ErrorReporter& _errorReporter,
langutil::EVMVersion _evmVersion,
bool _errorRecovery = false
):
ParserBase(_errorReporter, _errorRecovery),
m_evmVersion(_evmVersion)
{}
ASTPointer<SourceUnit> parse(std::shared_ptr<langutil::Scanner> const& _scanner);
private:
class ASTNodeFactory;
enum class VarDeclKind { FileLevel, State, Other };
struct VarDeclParserOptions
{
// This is actually not needed, but due to a defect in the C++ standard, we have to.
// https://stackoverflow.com/questions/17430377
VarDeclParserOptions() {}
VarDeclKind kind = VarDeclKind::Other;
bool allowIndexed = false;
bool allowEmptyName = false;
bool allowInitialValue = false;
bool allowLocationSpecifier = false;
};
/// This struct is shared for parsing a function header and a function type.
struct FunctionHeaderParserResult
{
bool isVirtual = false;
ASTPointer<OverrideSpecifier> overrides;
ASTPointer<ParameterList> parameters;
ASTPointer<ParameterList> returnParameters;
Visibility visibility = Visibility::Default;
StateMutability stateMutability = StateMutability::NonPayable;
std::vector<ASTPointer<ModifierInvocation>> modifiers;
};
///@{
///@name Parsing functions for the AST nodes
void parsePragmaVersion(langutil::SourceLocation const& _location, std::vector<Token> const& _tokens, std::vector<std::string> const& _literals);
ASTPointer<StructuredDocumentation> parseStructuredDocumentation();
ASTPointer<PragmaDirective> parsePragmaDirective();
ASTPointer<ImportDirective> parseImportDirective();
/// @returns an std::pair<ContractKind, bool>, where
/// result.second is set to true, if an abstract contract was parsed, false otherwise.
std::pair<ContractKind, bool> parseContractKind();
ASTPointer<ContractDefinition> parseContractDefinition();
ASTPointer<InheritanceSpecifier> parseInheritanceSpecifier();
Visibility parseVisibilitySpecifier();
ASTPointer<OverrideSpecifier> parseOverrideSpecifier();
StateMutability parseStateMutability();
FunctionHeaderParserResult parseFunctionHeader(bool _isStateVariable);
ASTPointer<ASTNode> parseFunctionDefinition(bool _freeFunction = false);
ASTPointer<StructDefinition> parseStructDefinition();
ASTPointer<EnumDefinition> parseEnumDefinition();
ASTPointer<EnumValue> parseEnumValue();
ASTPointer<VariableDeclaration> parseVariableDeclaration(
VarDeclParserOptions const& _options = {},
ASTPointer<TypeName> const& _lookAheadArrayType = ASTPointer<TypeName>()
);
ASTPointer<ModifierDefinition> parseModifierDefinition();
ASTPointer<EventDefinition> parseEventDefinition();
ASTPointer<UsingForDirective> parseUsingDirective();
ASTPointer<ModifierInvocation> parseModifierInvocation();
ASTPointer<Identifier> parseIdentifier();
ASTPointer<UserDefinedTypeName> parseUserDefinedTypeName();
ASTPointer<IdentifierPath> parseIdentifierPath();
ASTPointer<TypeName> parseTypeNameSuffix(ASTPointer<TypeName> type, ASTNodeFactory& nodeFactory);
ASTPointer<TypeName> parseTypeName();
ASTPointer<FunctionTypeName> parseFunctionType();
ASTPointer<Mapping> parseMapping();
ASTPointer<ParameterList> parseParameterList(
VarDeclParserOptions const& _options = {},
bool _allowEmpty = true
);
ASTPointer<Block> parseBlock(bool _allowUncheckedBlock = false, ASTPointer<ASTString> const& _docString = {});
ASTPointer<Statement> parseStatement(bool _allowUncheckedBlock = false);
ASTPointer<InlineAssembly> parseInlineAssembly(ASTPointer<ASTString> const& _docString = {});
ASTPointer<IfStatement> parseIfStatement(ASTPointer<ASTString> const& _docString);
ASTPointer<TryStatement> parseTryStatement(ASTPointer<ASTString> const& _docString);
ASTPointer<TryCatchClause> parseCatchClause();
ASTPointer<WhileStatement> parseWhileStatement(ASTPointer<ASTString> const& _docString);
ASTPointer<WhileStatement> parseDoWhileStatement(ASTPointer<ASTString> const& _docString);
ASTPointer<ForStatement> parseForStatement(ASTPointer<ASTString> const& _docString);
ASTPointer<EmitStatement> parseEmitStatement(ASTPointer<ASTString> const& docString);
/// A "simple statement" can be a variable declaration statement or an expression statement.
ASTPointer<Statement> parseSimpleStatement(ASTPointer<ASTString> const& _docString);
ASTPointer<VariableDeclarationStatement> parseVariableDeclarationStatement(
ASTPointer<ASTString> const& _docString,
ASTPointer<TypeName> const& _lookAheadArrayType = ASTPointer<TypeName>()
);
ASTPointer<ExpressionStatement> parseExpressionStatement(
ASTPointer<ASTString> const& _docString,
ASTPointer<Expression> const& _partiallyParsedExpression = ASTPointer<Expression>()
);
ASTPointer<Expression> parseExpression(
ASTPointer<Expression> const& _partiallyParsedExpression = ASTPointer<Expression>()
);
ASTPointer<Expression> parseBinaryExpression(int _minPrecedence = 4,
ASTPointer<Expression> const& _partiallyParsedExpression = ASTPointer<Expression>()
);
ASTPointer<Expression> parseUnaryExpression(
ASTPointer<Expression> const& _partiallyParsedExpression = ASTPointer<Expression>()
);
ASTPointer<Expression> parseLeftHandSideExpression(
ASTPointer<Expression> const& _partiallyParsedExpression = ASTPointer<Expression>()
);
ASTPointer<Expression> parsePrimaryExpression();
std::vector<ASTPointer<Expression>> parseFunctionCallListArguments();
std::pair<std::vector<ASTPointer<Expression>>, std::vector<ASTPointer<ASTString>>> parseFunctionCallArguments();
std::pair<std::vector<ASTPointer<Expression>>, std::vector<ASTPointer<ASTString>>> parseNamedArguments();
///@}
///@{
///@name Helper functions
/// @return true if we are at the start of a variable declaration.
bool variableDeclarationStart();
/// Used as return value of @see peekStatementType.
enum class LookAheadInfo
{
IndexAccessStructure, VariableDeclaration, Expression
};
/// Structure that represents a.b.c[x][y][z]. Can be converted either to an expression
/// or to a type name. For this to be valid, path cannot be empty, but indices can be empty.
struct IndexAccessedPath
{
struct Index
{
ASTPointer<Expression> start;
std::optional<ASTPointer<Expression>> end;
langutil::SourceLocation location;
};
std::vector<ASTPointer<PrimaryExpression>> path;
std::vector<Index> indices;
bool empty() const;
};
std::optional<std::string> findLicenseString(std::vector<ASTPointer<ASTNode>> const& _nodes);
/// Returns the next AST node ID
int64_t nextID() { return ++m_currentNodeID; }
std::pair<LookAheadInfo, IndexAccessedPath> tryParseIndexAccessedPath();
/// Performs limited look-ahead to distinguish between variable declaration and expression statement.
/// For source code of the form "a[][8]" ("IndexAccessStructure"), this is not possible to
/// decide with constant look-ahead.
LookAheadInfo peekStatementType() const;
/// @returns an IndexAccessedPath as a prestage to parsing a variable declaration (type name)
/// or an expression;
IndexAccessedPath parseIndexAccessedPath();
/// @returns a typename parsed in look-ahead fashion from something like "a.b[8][2**70]",
/// or an empty pointer if an empty @a _pathAndIncides has been supplied.
ASTPointer<TypeName> typeNameFromIndexAccessStructure(IndexAccessedPath const& _pathAndIndices);
/// @returns an expression parsed in look-ahead fashion from something like "a.b[8][2**70]",
/// or an empty pointer if an empty @a _pathAndIncides has been supplied.
ASTPointer<Expression> expressionFromIndexAccessStructure(IndexAccessedPath const& _pathAndIndices);
ASTPointer<ASTString> expectIdentifierToken();
ASTPointer<ASTString> getLiteralAndAdvance();
///@}
/// Creates an empty ParameterList at the current location (used if parameters can be omitted).
ASTPointer<ParameterList> createEmptyParameterList();
/// Flag that signifies whether '_' is parsed as a PlaceholderStatement or a regular identifier.
bool m_insideModifier = false;
langutil::EVMVersion m_evmVersion;
/// Counter for the next AST node ID
int64_t m_currentNodeID = 0;
};
}