Add optional types to function/method declarations

src/parsing/preparser.cc

 // 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"
@@ skipping 76 matching lines @@
 
 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,
-    LanguageMode language_mode, bool* ok) {
+    LanguageMode language_mode, typesystem::TypeFlags type_flags, bool* ok) {
   return pre_parser_->ParseFunctionLiteral(
       name, function_name_location, function_name_validity, kind,
-      function_token_position, type, language_mode, ok);
+      function_token_position, type, language_mode, type_flags, 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);
@@ skipping 301 matching lines @@
   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::kDeclaration, language_mode(),
-                       CHECK_OK);
+                       typesystem::kAllowSignature, 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();
@@ skipping 106 matching lines @@
       pattern = ParsePrimaryExpression(&pattern_classifier, CHECK_OK);
 
       ValidateBindingPattern(&pattern_classifier, CHECK_OK);
       if (lexical) {
         ValidateLetPattern(&pattern_classifier, CHECK_OK);
       }
     }
 
     is_pattern = pattern.IsObjectLiteral() || pattern.IsArrayLiteral();
 
-    // Optional type annotation.
-    if (scope_->typed() && Check(Token::COLON)) {
+    // Parse optional type annotation.
+    if (scope_->typed() && Check(Token::COLON)) {  // Braces required here.
       ParseValidType(CHECK_OK);
     }
 
     Scanner::Location variable_loc = scanner()->location();
     nvars++;
     if (Check(Token::ASSIGN)) {
       ExpressionClassifier classifier(this);
       ParseAssignmentExpression(var_context != kForStatement, &classifier,
                                 CHECK_OK);
       ValidateExpression(&classifier, CHECK_OK);
@@ skipping 441 matching lines @@
   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,
-    LanguageMode language_mode, bool* ok) {
+    LanguageMode language_mode, typesystem::TypeFlags type_flags, 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(this, &duplicate_finder);
 
+  // Parse optional type parameters.
+  if (scope_->typed() && !(type_flags & typesystem::kDisallowTypeParameters) &&
+      peek() == Token::LT) {  // Braces required here.
+    ParseTypeParameters(CHECK_OK);
+  }
+
   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, kind, 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;
 
+  // Parse optional type annotation.
+  if (scope_->typed() && Check(Token::COLON)) {  // Braces required here.
+    ParseValidType(CHECK_OK);
+  }
+
+  // Allow for a function signature (i.e., a literal without body).
+  if (peek() != Token::LBRACE && scope_->typed() &&
+      (type_flags & typesystem::kAllowSignature)) {
+    ExpectSemicolon(CHECK_OK);
+    return this->EmptyExpression();
+  }
+
   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();
@@ skipping 123 matching lines @@
     Expect(Token::RBRACE, CHECK_OK);
     return PreParserExpression::Default();
   }
 }
 
 #undef CHECK_OK
 
 
 }  // namespace internal
 }  // namespace v8