AuroraMiddleware/v8
1
0
Fork 0
Code Issues 2 Pull Requests Releases Wiki Activity
72bc4b5c8a
v8/src/preparser.cc
conradw 05f01b3f8e [strong] Class constructor bodies cannot contain "use strong" directive 
Since the constructor is also the class object itself, allowing it to
retroactively become a strong object would have unintuitive consequences
wrt the strength of the other functions of the class, and whether instances
would be considered instances of a strong class.

BUG=v8:3956
LOG=N

Review URL: https://codereview.chromium.org/1314203002

Cr-Commit-Position: refs/heads/master@{#30519}
2015-09-01 18:29:35 +00:00

1241 lines
41 KiB
C++
Raw Blame History

// Copyright 2011 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <cmath>
#include "src/allocation.h"
#include "src/base/logging.h"
#include "src/conversions-inl.h"
#include "src/conversions.h"
#include "src/globals.h"
#include "src/hashmap.h"
#include "src/list.h"
#include "src/preparse-data.h"
#include "src/preparse-data-format.h"
#include "src/preparser.h"
#include "src/unicode.h"
#include "src/utils.h"
namespace v8 {
namespace internal {
void PreParserTraits::ReportMessageAt(Scanner::Location location,
MessageTemplate::Template message,
const char* arg,
ParseErrorType error_type) {
ReportMessageAt(location.beg_pos, location.end_pos, message, arg, error_type);
}
void PreParserTraits::ReportMessageAt(int start_pos, int end_pos,
MessageTemplate::Template message,
const char* arg,
ParseErrorType error_type) {
pre_parser_->log_->LogMessage(start_pos, end_pos, message, arg, error_type);
}
PreParserIdentifier PreParserTraits::GetSymbol(Scanner* scanner) {
if (scanner->current_token() == Token::FUTURE_RESERVED_WORD) {
return PreParserIdentifier::FutureReserved();
} else if (scanner->current_token() ==
Token::FUTURE_STRICT_RESERVED_WORD) {
return PreParserIdentifier::FutureStrictReserved();
} else if (scanner->current_token() == Token::LET) {
return PreParserIdentifier::Let();
} else if (scanner->current_token() == Token::STATIC) {
return PreParserIdentifier::Static();
} else if (scanner->current_token() == Token::YIELD) {
return PreParserIdentifier::Yield();
}
if (scanner->UnescapedLiteralMatches("eval", 4)) {
return PreParserIdentifier::Eval();
}
if (scanner->UnescapedLiteralMatches("arguments", 9)) {
return PreParserIdentifier::Arguments();
}
if (scanner->UnescapedLiteralMatches("undefined", 9)) {
return PreParserIdentifier::Undefined();
}
if (scanner->LiteralMatches("prototype", 9)) {
return PreParserIdentifier::Prototype();
}
if (scanner->LiteralMatches("constructor", 11)) {
return PreParserIdentifier::Constructor();
}
return PreParserIdentifier::Default();
}
PreParserIdentifier PreParserTraits::GetNumberAsSymbol(Scanner* scanner) {
return PreParserIdentifier::Default();
}
PreParserExpression PreParserTraits::ExpressionFromString(
int pos, Scanner* scanner, PreParserFactory* factory) {
if (scanner->UnescapedLiteralMatches("use strict", 10)) {
return PreParserExpression::UseStrictStringLiteral();
} else if (scanner->UnescapedLiteralMatches("use strong", 10)) {
return PreParserExpression::UseStrongStringLiteral();
}
return PreParserExpression::StringLiteral();
}
PreParserExpression PreParserTraits::ParseV8Intrinsic(bool* ok) {
return pre_parser_->ParseV8Intrinsic(ok);
}
PreParserExpression PreParserTraits::ParseFunctionLiteral(
PreParserIdentifier name, Scanner::Location function_name_location,
FunctionNameValidity function_name_validity, FunctionKind kind,
int function_token_position, FunctionLiteral::FunctionType type,
FunctionLiteral::ArityRestriction arity_restriction,
LanguageMode language_mode, bool* ok) {
return pre_parser_->ParseFunctionLiteral(
name, function_name_location, function_name_validity, kind,
function_token_position, type, arity_restriction, language_mode, ok);
}
PreParser::PreParseResult PreParser::PreParseLazyFunction(
LanguageMode language_mode, FunctionKind kind, bool has_simple_parameters,
ParserRecorder* log, Scanner::BookmarkScope* bookmark) {
log_ = log;
// Lazy functions always have trivial outer scopes (no with/catch scopes).
Scope* top_scope = NewScope(scope_, SCRIPT_SCOPE);
PreParserFactory top_factory(NULL);
FunctionState top_state(&function_state_, &scope_, top_scope, kNormalFunction,
&top_factory);
scope_->SetLanguageMode(language_mode);
Scope* function_scope = NewScope(
scope_, IsArrowFunction(kind) ? ARROW_SCOPE : FUNCTION_SCOPE, kind);
if (!has_simple_parameters) function_scope->SetHasNonSimpleParameters();
PreParserFactory function_factory(NULL);
FunctionState function_state(&function_state_, &scope_, function_scope, kind,
&function_factory);
DCHECK_EQ(Token::LBRACE, scanner()->current_token());
bool ok = true;
int start_position = peek_position();
ParseLazyFunctionLiteralBody(&ok, bookmark);
if (bookmark && bookmark->HasBeenReset()) {
; // Do nothing, as we've just aborted scanning this function.
} else if (stack_overflow()) {
return kPreParseStackOverflow;
} else if (!ok) {
ReportUnexpectedToken(scanner()->current_token());
} else {
DCHECK_EQ(Token::RBRACE, scanner()->peek());
if (is_strict(scope_->language_mode())) {
int end_pos = scanner()->location().end_pos;
CheckStrictOctalLiteral(start_position, end_pos, &ok);
if (!ok) return kPreParseSuccess;
if (is_strong(scope_->language_mode()) && IsSubclassConstructor(kind)) {
if (!function_state.super_location().IsValid()) {
ReportMessageAt(Scanner::Location(start_position, start_position + 1),
MessageTemplate::kStrongSuperCallMissing,
kReferenceError);
return kPreParseSuccess;
}
}
}
}
return kPreParseSuccess;
}
PreParserExpression PreParserTraits::ParseClassLiteral(
PreParserIdentifier name, Scanner::Location class_name_location,
bool name_is_strict_reserved, int pos, bool* ok) {
return pre_parser_->ParseClassLiteral(name, class_name_location,
name_is_strict_reserved, pos, ok);
}
// Preparsing checks a JavaScript program and emits preparse-data that helps
// a later parsing to be faster.
// See preparser-data.h for the data.
// The PreParser checks that the syntax follows the grammar for JavaScript,
// and collects some information about the program along the way.
// The grammar check is only performed in order to understand the program
// sufficiently to deduce some information about it, that can be used
// to speed up later parsing. Finding errors is not the goal of pre-parsing,
// rather it is to speed up properly written and correct programs.
// That means that contextual checks (like a label being declared where
// it is used) are generally omitted.
PreParser::Statement PreParser::ParseStatementListItem(bool* ok) {
// ECMA 262 6th Edition
// StatementListItem[Yield, Return] :
// Statement[?Yield, ?Return]
// Declaration[?Yield]
//
// Declaration[Yield] :
// HoistableDeclaration[?Yield]
// ClassDeclaration[?Yield]
// LexicalDeclaration[In, ?Yield]
//
// HoistableDeclaration[Yield, Default] :
// FunctionDeclaration[?Yield, ?Default]
// GeneratorDeclaration[?Yield, ?Default]
//
// LexicalDeclaration[In, Yield] :
// LetOrConst BindingList[?In, ?Yield] ;
switch (peek()) {
case Token::FUNCTION:
return ParseFunctionDeclaration(ok);
case Token::CLASS:
return ParseClassDeclaration(ok);
case Token::CONST:
if (allow_const()) {
return ParseVariableStatement(kStatementListItem, ok);
}
break;
case Token::LET:
if (IsNextLetKeyword()) {
return ParseVariableStatement(kStatementListItem, ok);
}
break;
default:
break;
}
return ParseStatement(ok);
}
void PreParser::ParseStatementList(int end_token, bool* ok,
Scanner::BookmarkScope* bookmark) {
// SourceElements ::
// (Statement)* <end_token>
// Bookkeeping for trial parse if bookmark is set:
DCHECK_IMPLIES(bookmark, bookmark->HasBeenSet());
bool maybe_reset = bookmark != nullptr;
int count_statements = 0;
bool directive_prologue = true;
while (peek() != end_token) {
if (directive_prologue && peek() != Token::STRING) {
directive_prologue = false;
}
bool starts_with_identifier = peek() == Token::IDENTIFIER;
Scanner::Location token_loc = scanner()->peek_location();
Scanner::Location old_this_loc = function_state_->this_location();
Scanner::Location old_super_loc = function_state_->super_location();
Statement statement = ParseStatementListItem(ok);
if (!*ok) return;
if (is_strong(language_mode()) &&
scope_->is_function_scope() &&
i::IsConstructor(function_state_->kind())) {
Scanner::Location this_loc = function_state_->this_location();
Scanner::Location super_loc = function_state_->super_location();
if (this_loc.beg_pos != old_this_loc.beg_pos &&
this_loc.beg_pos != token_loc.beg_pos) {
ReportMessageAt(this_loc, MessageTemplate::kStrongConstructorThis);
*ok = false;
return;
}
if (super_loc.beg_pos != old_super_loc.beg_pos &&
super_loc.beg_pos != token_loc.beg_pos) {
ReportMessageAt(super_loc, MessageTemplate::kStrongConstructorSuper);
*ok = false;
return;
}
}
if (directive_prologue) {
bool use_strict_found = statement.IsUseStrictLiteral();
bool use_strong_found =
statement.IsUseStrongLiteral() && allow_strong_mode();
if (use_strict_found) {
scope_->SetLanguageMode(
static_cast<LanguageMode>(scope_->language_mode() | STRICT));
} else if (use_strong_found) {
scope_->SetLanguageMode(static_cast<LanguageMode>(
scope_->language_mode() | STRONG));
if (i::IsConstructor(function_state_->kind())) {
// "use strong" cannot occur in a class constructor body, to avoid
// unintuitive strong class object semantics.
PreParserTraits::ReportMessageAt(
token_loc, MessageTemplate::kStrongConstructorDirective);
*ok = false;
return;
}
} else if (!statement.IsStringLiteral()) {
directive_prologue = false;
}
if ((use_strict_found || use_strong_found) &&
!scope_->HasSimpleParameters()) {
// TC39 deemed "use strict" directives to be an error when occurring
// in the body of a function with non-simple parameter list, on
// 29/7/2015. https://goo.gl/ueA7Ln
//
// In V8, this also applies to "use strong " directives.
PreParserTraits::ReportMessageAt(
token_loc, MessageTemplate::kIllegalLanguageModeDirective,
use_strict_found ? "use strict" : "use strong");
*ok = false;
return;
}
}
// If we're allowed to reset to a bookmark, we will do so when we see a long
// and trivial function.
// Our current definition of 'long and trivial' is:
// - over 200 statements
// - all starting with an identifier (i.e., no if, for, while, etc.)
if (maybe_reset && (!starts_with_identifier ||
++count_statements > kLazyParseTrialLimit)) {
if (count_statements > kLazyParseTrialLimit) {
bookmark->Reset();
return;
}
maybe_reset = false;
}
}
}
#define CHECK_OK ok); \
if (!*ok) return Statement::Default(); \
((void)0
#define DUMMY ) // to make indentation work
#undef DUMMY
PreParser::Statement PreParser::ParseStatement(bool* ok) {
// Statement ::
// EmptyStatement
// ...
if (peek() == Token::SEMICOLON) {
Next();
return Statement::Default();
}
return ParseSubStatement(ok);
}
PreParser::Statement PreParser::ParseSubStatement(bool* ok) {
// Statement ::
// Block
// VariableStatement
// EmptyStatement
// ExpressionStatement
// IfStatement
// IterationStatement
// ContinueStatement
// BreakStatement
// ReturnStatement
// WithStatement
// LabelledStatement
// SwitchStatement
// ThrowStatement
// TryStatement
// DebuggerStatement
// Note: Since labels can only be used by 'break' and 'continue'
// statements, which themselves are only valid within blocks,
// iterations or 'switch' statements (i.e., BreakableStatements),
// labels can be simply ignored in all other cases; except for
// trivial labeled break statements 'label: break label' which is
// parsed into an empty statement.
// Keep the source position of the statement
switch (peek()) {
case Token::LBRACE:
return ParseBlock(ok);
case Token::SEMICOLON:
if (is_strong(language_mode())) {
PreParserTraits::ReportMessageAt(scanner()->peek_location(),
MessageTemplate::kStrongEmpty);
*ok = false;
return Statement::Default();
}
Next();
return Statement::Default();
case Token::IF:
return ParseIfStatement(ok);
case Token::DO:
return ParseDoWhileStatement(ok);
case Token::WHILE:
return ParseWhileStatement(ok);
case Token::FOR:
return ParseForStatement(ok);
case Token::CONTINUE:
return ParseContinueStatement(ok);
case Token::BREAK:
return ParseBreakStatement(ok);
case Token::RETURN:
return ParseReturnStatement(ok);
case Token::WITH:
return ParseWithStatement(ok);
case Token::SWITCH:
return ParseSwitchStatement(ok);
case Token::THROW:
return ParseThrowStatement(ok);
case Token::TRY:
return ParseTryStatement(ok);
case Token::FUNCTION: {
Scanner::Location start_location = scanner()->peek_location();
Statement statement = ParseFunctionDeclaration(CHECK_OK);
Scanner::Location end_location = scanner()->location();
if (is_strict(language_mode())) {
PreParserTraits::ReportMessageAt(start_location.beg_pos,
end_location.end_pos,
MessageTemplate::kStrictFunction);
*ok = false;
return Statement::Default();
} else {
return statement;
}
}
case Token::DEBUGGER:
return ParseDebuggerStatement(ok);
case Token::VAR:
return ParseVariableStatement(kStatement, ok);
case Token::CONST:
// In ES6 CONST is not allowed as a Statement, only as a
// LexicalDeclaration, however we continue to allow it in sloppy mode for
// backwards compatibility.
if (is_sloppy(language_mode()) && allow_legacy_const()) {
return ParseVariableStatement(kStatement, ok);
}
// Fall through.
default:
return ParseExpressionOrLabelledStatement(ok);
}
}
PreParser::Statement PreParser::ParseFunctionDeclaration(bool* ok) {
// FunctionDeclaration ::
// 'function' Identifier '(' FormalParameterListopt ')' '{' FunctionBody '}'
// GeneratorDeclaration ::
// 'function' '*' Identifier '(' FormalParameterListopt ')'
// '{' FunctionBody '}'
Expect(Token::FUNCTION, CHECK_OK);
int pos = position();
bool is_generator = Check(Token::MUL);
bool is_strict_reserved = false;
Identifier name = ParseIdentifierOrStrictReservedWord(
&is_strict_reserved, CHECK_OK);
ParseFunctionLiteral(name, scanner()->location(),
is_strict_reserved ? kFunctionNameIsStrictReserved
: kFunctionNameValidityUnknown,
is_generator ? FunctionKind::kGeneratorFunction
: FunctionKind::kNormalFunction,
pos, FunctionLiteral::DECLARATION,
FunctionLiteral::NORMAL_ARITY, language_mode(),
CHECK_OK);
return Statement::FunctionDeclaration();
}
PreParser::Statement PreParser::ParseClassDeclaration(bool* ok) {
Expect(Token::CLASS, CHECK_OK);
if (!allow_harmony_sloppy() && is_sloppy(language_mode())) {
ReportMessage(MessageTemplate::kSloppyLexical);
*ok = false;
return Statement::Default();
}
int pos = position();
bool is_strict_reserved = false;
Identifier name =
ParseIdentifierOrStrictReservedWord(&is_strict_reserved, CHECK_OK);
ParseClassLiteral(name, scanner()->location(), is_strict_reserved, pos,
CHECK_OK);
return Statement::Default();
}
PreParser::Statement PreParser::ParseBlock(bool* ok) {
// Block ::
// '{' Statement* '}'
// Note that a Block does not introduce a new execution scope!
// (ECMA-262, 3rd, 12.2)
//
Expect(Token::LBRACE, CHECK_OK);
Statement final = Statement::Default();
while (peek() != Token::RBRACE) {
if (is_strict(language_mode()) || allow_harmony_sloppy()) {
final = ParseStatementListItem(CHECK_OK);
} else {
final = ParseStatement(CHECK_OK);
}
}
Expect(Token::RBRACE, ok);
return final;
}
PreParser::Statement PreParser::ParseVariableStatement(
VariableDeclarationContext var_context,
bool* ok) {
// VariableStatement ::
// VariableDeclarations ';'
Statement result = ParseVariableDeclarations(var_context, nullptr, nullptr,
nullptr, CHECK_OK);
ExpectSemicolon(CHECK_OK);
return result;
}
// If the variable declaration declares exactly one non-const
// variable, then *var is set to that variable. In all other cases,
// *var is untouched; in particular, it is the caller's responsibility
// to initialize it properly. This mechanism is also used for the parsing
// of 'for-in' loops.
PreParser::Statement PreParser::ParseVariableDeclarations(
VariableDeclarationContext var_context, int* num_decl,
Scanner::Location* first_initializer_loc, Scanner::Location* bindings_loc,
bool* ok) {
// VariableDeclarations ::
// ('var' | 'const') (Identifier ('=' AssignmentExpression)?)+[',']
//
// The ES6 Draft Rev3 specifies the following grammar for const declarations
//
// ConstDeclaration ::
// const ConstBinding (',' ConstBinding)* ';'
// ConstBinding ::
// Identifier '=' AssignmentExpression
//
// TODO(ES6):
// ConstBinding ::
// BindingPattern '=' AssignmentExpression
bool require_initializer = false;
bool is_strict_const = false;
if (peek() == Token::VAR) {
if (is_strong(language_mode())) {
Scanner::Location location = scanner()->peek_location();
ReportMessageAt(location, MessageTemplate::kStrongVar);
*ok = false;
return Statement::Default();
}
Consume(Token::VAR);
} else if (peek() == Token::CONST && allow_const()) {
// TODO(ES6): The ES6 Draft Rev4 section 12.2.2 reads:
//
// ConstDeclaration : const ConstBinding (',' ConstBinding)* ';'
//
// * It is a Syntax Error if the code that matches this production is not
// contained in extended code.
//
// However disallowing const in sloppy mode will break compatibility with
// existing pages. Therefore we keep allowing const with the old
// non-harmony semantics in sloppy mode.
Consume(Token::CONST);
if (is_strict(language_mode()) ||
(allow_harmony_sloppy() && !allow_legacy_const())) {
DCHECK(var_context != kStatement);
is_strict_const = true;
require_initializer = var_context != kForStatement;
}
} else if (peek() == Token::LET && allow_let()) {
Consume(Token::LET);
DCHECK(var_context != kStatement);
} else {
*ok = false;
return Statement::Default();
}
// The scope of a var/const declared variable anywhere inside a function
// is the entire function (ECMA-262, 3rd, 10.1.3, and 12.2). The scope
// of a let declared variable is the scope of the immediately enclosing
// block.
int nvars = 0; // the number of variables declared
int bindings_start = peek_position();
do {
// Parse binding pattern.
if (nvars > 0) Consume(Token::COMMA);
{
ExpressionClassifier pattern_classifier;
Token::Value next = peek();
PreParserExpression pattern =
ParsePrimaryExpression(&pattern_classifier, CHECK_OK);
ValidateBindingPattern(&pattern_classifier, CHECK_OK);
if (!allow_harmony_destructuring() && !pattern.IsIdentifier()) {
ReportUnexpectedToken(next);
*ok = false;
return Statement::Default();
}
}
Scanner::Location variable_loc = scanner()->location();
nvars++;
if (peek() == Token::ASSIGN || require_initializer ||
// require initializers for multiple consts.
(is_strict_const && peek() == Token::COMMA)) {
Expect(Token::ASSIGN, CHECK_OK);
ExpressionClassifier classifier;
ParseAssignmentExpression(var_context != kForStatement, &classifier,
CHECK_OK);
ValidateExpression(&classifier, CHECK_OK);
variable_loc.end_pos = scanner()->location().end_pos;
if (first_initializer_loc && !first_initializer_loc->IsValid()) {
*first_initializer_loc = variable_loc;
}
}
} while (peek() == Token::COMMA);
if (bindings_loc) {
*bindings_loc =
Scanner::Location(bindings_start, scanner()->location().end_pos);
}
if (num_decl != NULL) *num_decl = nvars;
return Statement::Default();
}
PreParser::Statement PreParser::ParseExpressionOrLabelledStatement(bool* ok) {
// ExpressionStatement | LabelledStatement ::
// Expression ';'
// Identifier ':' Statement
switch (peek()) {
case Token::FUNCTION:
case Token::LBRACE:
UNREACHABLE(); // Always handled by the callers.
case Token::CLASS:
ReportUnexpectedToken(Next());
*ok = false;
return Statement::Default();
case Token::THIS:
if (!FLAG_strong_this) break;
// Fall through.
case Token::SUPER:
if (is_strong(language_mode()) &&
i::IsConstructor(function_state_->kind())) {
bool is_this = peek() == Token::THIS;
Expression expr = Expression::Default();
ExpressionClassifier classifier;
if (is_this) {
expr = ParseStrongInitializationExpression(&classifier, CHECK_OK);
} else {
expr = ParseStrongSuperCallExpression(&classifier, CHECK_OK);
}
ValidateExpression(&classifier, CHECK_OK);
switch (peek()) {
case Token::SEMICOLON:
Consume(Token::SEMICOLON);
break;
case Token::RBRACE:
case Token::EOS:
break;
default:
if (!scanner()->HasAnyLineTerminatorBeforeNext()) {
ReportMessageAt(function_state_->this_location(),
is_this
? MessageTemplate::kStrongConstructorThis
: MessageTemplate::kStrongConstructorSuper);
*ok = false;
return Statement::Default();
}
}
return Statement::ExpressionStatement(expr);
}
break;
// TODO(arv): Handle `let [`
// https://code.google.com/p/v8/issues/detail?id=3847
default:
break;
}
bool starts_with_identifier = peek_any_identifier();
ExpressionClassifier classifier;
Expression expr = ParseExpression(true, &classifier, CHECK_OK);
ValidateExpression(&classifier, CHECK_OK);
// Even if the expression starts with an identifier, it is not necessarily an
// identifier. For example, "foo + bar" starts with an identifier but is not
// an identifier.
if (starts_with_identifier && expr.IsIdentifier() && peek() == Token::COLON) {
// Expression is a single identifier, and not, e.g., a parenthesized
// identifier.
DCHECK(!expr.AsIdentifier().IsFutureReserved());
DCHECK(is_sloppy(language_mode()) ||
!IsFutureStrictReserved(expr.AsIdentifier()));
Consume(Token::COLON);
Statement statement = ParseStatement(ok);
return statement.IsJumpStatement() ? Statement::Default() : statement;
// Preparsing is disabled for extensions (because the extension details
// aren't passed to lazily compiled functions), so we don't
// accept "native function" in the preparser.
}
// Parsed expression statement.
// Detect attempts at 'let' declarations in sloppy mode.
if (peek() == Token::IDENTIFIER && is_sloppy(language_mode()) &&
expr.IsIdentifier() && expr.AsIdentifier().IsLet()) {
ReportMessage(MessageTemplate::kSloppyLexical, NULL);
*ok = false;
return Statement::Default();
}
ExpectSemicolon(CHECK_OK);
return Statement::ExpressionStatement(expr);
}
PreParser::Statement PreParser::ParseIfStatement(bool* ok) {
// IfStatement ::
// 'if' '(' Expression ')' Statement ('else' Statement)?
Expect(Token::IF, CHECK_OK);
Expect(Token::LPAREN, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(Token::RPAREN, CHECK_OK);
Statement stat = ParseSubStatement(CHECK_OK);
if (peek() == Token::ELSE) {
Next();
Statement else_stat = ParseSubStatement(CHECK_OK);
stat = (stat.IsJumpStatement() && else_stat.IsJumpStatement()) ?
Statement::Jump() : Statement::Default();
} else {
stat = Statement::Default();
}
return stat;
}
PreParser::Statement PreParser::ParseContinueStatement(bool* ok) {
// ContinueStatement ::
// 'continue' [no line terminator] Identifier? ';'
Expect(Token::CONTINUE, CHECK_OK);
Token::Value tok = peek();
if (!scanner()->HasAnyLineTerminatorBeforeNext() &&
tok != Token::SEMICOLON &&
tok != Token::RBRACE &&
tok != Token::EOS) {
// ECMA allows "eval" or "arguments" as labels even in strict mode.
ParseIdentifier(kAllowRestrictedIdentifiers, CHECK_OK);
}
ExpectSemicolon(CHECK_OK);
return Statement::Jump();
}
PreParser::Statement PreParser::ParseBreakStatement(bool* ok) {
// BreakStatement ::
// 'break' [no line terminator] Identifier? ';'
Expect(Token::BREAK, CHECK_OK);
Token::Value tok = peek();
if (!scanner()->HasAnyLineTerminatorBeforeNext() &&
tok != Token::SEMICOLON &&
tok != Token::RBRACE &&
tok != Token::EOS) {
// ECMA allows "eval" or "arguments" as labels even in strict mode.
ParseIdentifier(kAllowRestrictedIdentifiers, CHECK_OK);
}
ExpectSemicolon(CHECK_OK);
return Statement::Jump();
}
PreParser::Statement PreParser::ParseReturnStatement(bool* ok) {
// ReturnStatement ::
// 'return' [no line terminator] Expression? ';'
// Consume the return token. It is necessary to do before
// reporting any errors on it, because of the way errors are
// reported (underlining).
Expect(Token::RETURN, CHECK_OK);
function_state_->set_return_location(scanner()->location());
// An ECMAScript program is considered syntactically incorrect if it
// contains a return statement that is not within the body of a
// function. See ECMA-262, section 12.9, page 67.
// This is not handled during preparsing.
Token::Value tok = peek();
if (!scanner()->HasAnyLineTerminatorBeforeNext() &&
tok != Token::SEMICOLON &&
tok != Token::RBRACE &&
tok != Token::EOS) {
if (is_strong(language_mode()) &&
i::IsConstructor(function_state_->kind())) {
int pos = peek_position();
ReportMessageAt(Scanner::Location(pos, pos + 1),
MessageTemplate::kStrongConstructorReturnValue);
*ok = false;
return Statement::Default();
}
ParseExpression(true, CHECK_OK);
}
ExpectSemicolon(CHECK_OK);
return Statement::Jump();
}
PreParser::Statement PreParser::ParseWithStatement(bool* ok) {
// WithStatement ::
// 'with' '(' Expression ')' Statement
Expect(Token::WITH, CHECK_OK);
if (is_strict(language_mode())) {
ReportMessageAt(scanner()->location(), MessageTemplate::kStrictWith);
*ok = false;
return Statement::Default();
}
Expect(Token::LPAREN, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(Token::RPAREN, CHECK_OK);
Scope* with_scope = NewScope(scope_, WITH_SCOPE);
BlockState block_state(&scope_, with_scope);
ParseSubStatement(CHECK_OK);
return Statement::Default();
}
PreParser::Statement PreParser::ParseSwitchStatement(bool* ok) {
// SwitchStatement ::
// 'switch' '(' Expression ')' '{' CaseClause* '}'
Expect(Token::SWITCH, CHECK_OK);
Expect(Token::LPAREN, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(Token::RPAREN, CHECK_OK);
Expect(Token::LBRACE, CHECK_OK);
Token::Value token = peek();
while (token != Token::RBRACE) {
if (token == Token::CASE) {
Expect(Token::CASE, CHECK_OK);
ParseExpression(true, CHECK_OK);
} else {
Expect(Token::DEFAULT, CHECK_OK);
}
Expect(Token::COLON, CHECK_OK);
token = peek();
Statement statement = Statement::Jump();
while (token != Token::CASE &&
token != Token::DEFAULT &&
token != Token::RBRACE) {
statement = ParseStatementListItem(CHECK_OK);
token = peek();
}
if (is_strong(language_mode()) && !statement.IsJumpStatement() &&
token != Token::RBRACE) {
ReportMessageAt(scanner()->location(),
MessageTemplate::kStrongSwitchFallthrough);
*ok = false;
return Statement::Default();
}
}
Expect(Token::RBRACE, ok);
return Statement::Default();
}
PreParser::Statement PreParser::ParseDoWhileStatement(bool* ok) {
// DoStatement ::
// 'do' Statement 'while' '(' Expression ')' ';'
Expect(Token::DO, CHECK_OK);
ParseSubStatement(CHECK_OK);
Expect(Token::WHILE, CHECK_OK);
Expect(Token::LPAREN, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(Token::RPAREN, ok);
if (peek() == Token::SEMICOLON) Consume(Token::SEMICOLON);
return Statement::Default();
}
PreParser::Statement PreParser::ParseWhileStatement(bool* ok) {
// WhileStatement ::
// 'while' '(' Expression ')' Statement
Expect(Token::WHILE, CHECK_OK);
Expect(Token::LPAREN, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(Token::RPAREN, CHECK_OK);
ParseSubStatement(ok);
return Statement::Default();
}
PreParser::Statement PreParser::ParseForStatement(bool* ok) {
// ForStatement ::
// 'for' '(' Expression? ';' Expression? ';' Expression? ')' Statement
Expect(Token::FOR, CHECK_OK);
Expect(Token::LPAREN, CHECK_OK);
bool is_let_identifier_expression = false;
if (peek() != Token::SEMICOLON) {
ForEachStatement::VisitMode mode;
if (peek() == Token::VAR || (peek() == Token::CONST && allow_const()) ||
(peek() == Token::LET && IsNextLetKeyword())) {
int decl_count;
Scanner::Location first_initializer_loc = Scanner::Location::invalid();
Scanner::Location bindings_loc = Scanner::Location::invalid();
ParseVariableDeclarations(kForStatement, &decl_count,
&first_initializer_loc, &bindings_loc,
CHECK_OK);
bool accept_IN = decl_count >= 1;
bool accept_OF = true;
if (accept_IN && CheckInOrOf(accept_OF, &mode, ok)) {
if (!*ok) return Statement::Default();
if (decl_count != 1) {
const char* loop_type =
mode == ForEachStatement::ITERATE ? "for-of" : "for-in";
PreParserTraits::ReportMessageAt(
bindings_loc, MessageTemplate::kForInOfLoopMultiBindings,
loop_type);
*ok = false;
return Statement::Default();
}
if (first_initializer_loc.IsValid() &&
(is_strict(language_mode()) || mode == ForEachStatement::ITERATE)) {
if (mode == ForEachStatement::ITERATE) {
ReportMessageAt(first_initializer_loc,
MessageTemplate::kForOfLoopInitializer);
} else {
// TODO(caitp): This should be an error in sloppy mode, too.
ReportMessageAt(first_initializer_loc,
MessageTemplate::kForInLoopInitializer);
}
*ok = false;
return Statement::Default();
}
ParseExpression(true, CHECK_OK);
Expect(Token::RPAREN, CHECK_OK);
ParseSubStatement(CHECK_OK);
return Statement::Default();
}
} else {
int lhs_beg_pos = peek_position();
Expression lhs = ParseExpression(false, CHECK_OK);
int lhs_end_pos = scanner()->location().end_pos;
is_let_identifier_expression =
lhs.IsIdentifier() && lhs.AsIdentifier().IsLet();
if (CheckInOrOf(lhs.IsIdentifier(), &mode, ok)) {
if (!*ok) return Statement::Default();
lhs = CheckAndRewriteReferenceExpression(
lhs, lhs_beg_pos, lhs_end_pos, MessageTemplate::kInvalidLhsInFor,
kSyntaxError, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(Token::RPAREN, CHECK_OK);
ParseSubStatement(CHECK_OK);
return Statement::Default();
}
}
}
// Parsed initializer at this point.
// Detect attempts at 'let' declarations in sloppy mode.
if (peek() == Token::IDENTIFIER && is_sloppy(language_mode()) &&
is_let_identifier_expression) {
ReportMessage(MessageTemplate::kSloppyLexical, NULL);
*ok = false;
return Statement::Default();
}
Expect(Token::SEMICOLON, CHECK_OK);
if (peek() != Token::SEMICOLON) {
ParseExpression(true, CHECK_OK);
}
Expect(Token::SEMICOLON, CHECK_OK);
if (peek() != Token::RPAREN) {
ParseExpression(true, CHECK_OK);
}
Expect(Token::RPAREN, CHECK_OK);
ParseSubStatement(ok);
return Statement::Default();
}
PreParser::Statement PreParser::ParseThrowStatement(bool* ok) {
// ThrowStatement ::
// 'throw' [no line terminator] Expression ';'
Expect(Token::THROW, CHECK_OK);
if (scanner()->HasAnyLineTerminatorBeforeNext()) {
ReportMessageAt(scanner()->location(), MessageTemplate::kNewlineAfterThrow);
*ok = false;
return Statement::Default();
}
ParseExpression(true, CHECK_OK);
ExpectSemicolon(ok);
return Statement::Jump();
}
PreParser::Statement PreParser::ParseTryStatement(bool* ok) {
// TryStatement ::
// 'try' Block Catch
// 'try' Block Finally
// 'try' Block Catch Finally
//
// Catch ::
// 'catch' '(' Identifier ')' Block
//
// Finally ::
// 'finally' Block
Expect(Token::TRY, CHECK_OK);
ParseBlock(CHECK_OK);
Token::Value tok = peek();
if (tok != Token::CATCH && tok != Token::FINALLY) {
ReportMessageAt(scanner()->location(), MessageTemplate::kNoCatchOrFinally);
*ok = false;
return Statement::Default();
}
if (tok == Token::CATCH) {
Consume(Token::CATCH);
Expect(Token::LPAREN, CHECK_OK);
ParseIdentifier(kDontAllowRestrictedIdentifiers, CHECK_OK);
Expect(Token::RPAREN, CHECK_OK);
{
Scope* with_scope = NewScope(scope_, WITH_SCOPE);
BlockState block_state(&scope_, with_scope);
ParseBlock(CHECK_OK);
}
tok = peek();
}
if (tok == Token::FINALLY) {
Consume(Token::FINALLY);
ParseBlock(CHECK_OK);
}
return Statement::Default();
}
PreParser::Statement PreParser::ParseDebuggerStatement(bool* ok) {
// In ECMA-262 'debugger' is defined as a reserved keyword. In some browser
// contexts this is used as a statement which invokes the debugger as if a
// break point is present.
// DebuggerStatement ::
// 'debugger' ';'
Expect(Token::DEBUGGER, CHECK_OK);
ExpectSemicolon(ok);
return Statement::Default();
}
#undef CHECK_OK
#define CHECK_OK ok); \
if (!*ok) return Expression::Default(); \
((void)0
#define DUMMY ) // to make indentation work
#undef DUMMY
PreParser::Expression PreParser::ParseFunctionLiteral(
Identifier function_name, Scanner::Location function_name_location,
FunctionNameValidity function_name_validity, FunctionKind kind,
int function_token_pos, FunctionLiteral::FunctionType function_type,
FunctionLiteral::ArityRestriction arity_restriction,
LanguageMode language_mode, bool* ok) {
// Function ::
// '(' FormalParameterList? ')' '{' FunctionBody '}'
// Parse function body.
bool outer_is_script_scope = scope_->is_script_scope();
Scope* function_scope = NewScope(scope_, FUNCTION_SCOPE, kind);
function_scope->SetLanguageMode(language_mode);
PreParserFactory factory(NULL);
FunctionState function_state(&function_state_, &scope_, function_scope, kind,
&factory);
DuplicateFinder duplicate_finder(scanner()->unicode_cache());
ExpressionClassifier formals_classifier(&duplicate_finder);
Expect(Token::LPAREN, CHECK_OK);
int start_position = scanner()->location().beg_pos;
function_scope->set_start_position(start_position);
PreParserFormalParameters formals(function_scope);
ParseFormalParameterList(&formals, &formals_classifier, CHECK_OK);
Expect(Token::RPAREN, CHECK_OK);
int formals_end_position = scanner()->location().end_pos;
CheckArityRestrictions(formals.arity, arity_restriction,
formals.has_rest, start_position,
formals_end_position, CHECK_OK);
// See Parser::ParseFunctionLiteral for more information about lazy parsing
// and lazy compilation.
bool is_lazily_parsed =
(outer_is_script_scope && allow_lazy() && !parenthesized_function_);
parenthesized_function_ = false;
Expect(Token::LBRACE, CHECK_OK);
if (is_lazily_parsed) {
ParseLazyFunctionLiteralBody(CHECK_OK);
} else {
ParseStatementList(Token::RBRACE, CHECK_OK);
}
Expect(Token::RBRACE, CHECK_OK);
// Parsing the body may change the language mode in our scope.
language_mode = function_scope->language_mode();
// Validate name and parameter names. We can do this only after parsing the
// function, since the function can declare itself strict.
CheckFunctionName(language_mode, function_name, function_name_validity,
function_name_location, CHECK_OK);
const bool allow_duplicate_parameters =
is_sloppy(language_mode) && formals.is_simple && !IsConciseMethod(kind);
ValidateFormalParameters(&formals_classifier, language_mode,
allow_duplicate_parameters, CHECK_OK);
if (is_strict(language_mode)) {
int end_position = scanner()->location().end_pos;
CheckStrictOctalLiteral(start_position, end_position, CHECK_OK);
}
if (is_strong(language_mode) && IsSubclassConstructor(kind)) {
if (!function_state.super_location().IsValid()) {
ReportMessageAt(function_name_location,
MessageTemplate::kStrongSuperCallMissing,
kReferenceError);
*ok = false;
return Expression::Default();
}
}
return Expression::Default();
}
void PreParser::ParseLazyFunctionLiteralBody(bool* ok,
Scanner::BookmarkScope* bookmark) {
int body_start = position();
ParseStatementList(Token::RBRACE, ok, bookmark);
if (!*ok) return;
if (bookmark && bookmark->HasBeenReset()) return;
// Position right after terminal '}'.
DCHECK_EQ(Token::RBRACE, scanner()->peek());
int body_end = scanner()->peek_location().end_pos;
log_->LogFunction(body_start, body_end,
function_state_->materialized_literal_count(),
function_state_->expected_property_count(), language_mode(),
scope_->uses_super_property(), scope_->calls_eval());
}
PreParserExpression PreParser::ParseClassLiteral(
PreParserIdentifier name, Scanner::Location class_name_location,
bool name_is_strict_reserved, int pos, bool* ok) {
// All parts of a ClassDeclaration and ClassExpression are strict code.
if (name_is_strict_reserved) {
ReportMessageAt(class_name_location,
MessageTemplate::kUnexpectedStrictReserved);
*ok = false;
return EmptyExpression();
}
if (IsEvalOrArguments(name)) {
ReportMessageAt(class_name_location, MessageTemplate::kStrictEvalArguments);
*ok = false;
return EmptyExpression();
}
LanguageMode class_language_mode = language_mode();
if (is_strong(class_language_mode) && IsUndefined(name)) {
ReportMessageAt(class_name_location, MessageTemplate::kStrongUndefined);
*ok = false;
return EmptyExpression();
}
Scope* scope = NewScope(scope_, BLOCK_SCOPE);
BlockState block_state(&scope_, scope);
scope_->SetLanguageMode(
static_cast<LanguageMode>(class_language_mode | STRICT));
// TODO(marja): Make PreParser use scope names too.
// scope_->SetScopeName(name);
bool has_extends = Check(Token::EXTENDS);
if (has_extends) {
ExpressionClassifier classifier;
ParseLeftHandSideExpression(&classifier, CHECK_OK);
ValidateExpression(&classifier, CHECK_OK);
}
ClassLiteralChecker checker(this);
bool has_seen_constructor = false;
Expect(Token::LBRACE, CHECK_OK);
while (peek() != Token::RBRACE) {
if (Check(Token::SEMICOLON)) continue;
const bool in_class = true;
const bool is_static = false;
bool is_computed_name = false; // Classes do not care about computed
// property names here.
ExpressionClassifier classifier;
ParsePropertyDefinition(&checker, in_class, has_extends, is_static,
&is_computed_name, &has_seen_constructor,
&classifier, CHECK_OK);
ValidateExpression(&classifier, CHECK_OK);
}
Expect(Token::RBRACE, CHECK_OK);
return Expression::Default();
}
PreParser::Expression PreParser::ParseV8Intrinsic(bool* ok) {
// CallRuntime ::
// '%' Identifier Arguments
Expect(Token::MOD, CHECK_OK);
if (!allow_natives()) {
*ok = false;
return Expression::Default();
}
// Allow "eval" or "arguments" for backward compatibility.
ParseIdentifier(kAllowRestrictedIdentifiers, CHECK_OK);
Scanner::Location spread_pos;
ExpressionClassifier classifier;
ParseArguments(&spread_pos, &classifier, ok);
ValidateExpression(&classifier, CHECK_OK);
DCHECK(!spread_pos.IsValid());
return Expression::Default();
}
#undef CHECK_OK
} } // v8::internal
Reference in New Issue View Git Blame Copy Permalink