Re-apply formal argument, arrow function parsing refactors

src/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 908 matching lines @@
     FunctionLiteral::ArityRestriction arity_restriction, bool* ok) {
   // Function ::
   //   '(' FormalParameterList? ')' '{' FunctionBody '}'
 
   // Parse function body.
   bool outer_is_script_scope = scope_->is_script_scope();
   Scope* function_scope = NewScope(scope_, FUNCTION_SCOPE);
   PreParserFactory factory(NULL);
   FunctionState function_state(&function_state_, &scope_, function_scope, kind,
                                &factory);
-  //  FormalParameterList ::
-  //    '(' (Identifier)*[','] ')'
-  Expect(Token::LPAREN, CHECK_OK);
-  int start_position = position();
-  DuplicateFinder duplicate_finder(scanner()->unicode_cache());
-  // We don't yet know if the function will be strict, so we cannot yet produce
-  // errors for parameter names or duplicates. However, we remember the
-  // locations of these errors if they occur and produce the errors later.
-  Scanner::Location eval_args_loc = Scanner::Location::invalid();
-  Scanner::Location dupe_loc = Scanner::Location::invalid();
-  Scanner::Location reserved_loc = Scanner::Location::invalid();
-
-  // Similarly for strong mode.
-  Scanner::Location undefined_loc = Scanner::Location::invalid();
+  FormalParameterErrorLocations error_locs;
 
   bool is_rest = false;
-  bool done = arity_restriction == FunctionLiteral::GETTER_ARITY ||
-      (peek() == Token::RPAREN &&
-       arity_restriction != FunctionLiteral::SETTER_ARITY);
-  while (!done) {
-    bool is_strict_reserved = false;
-    is_rest = peek() == Token::ELLIPSIS && allow_harmony_rest_params();
-    if (is_rest) {
-      Consume(Token::ELLIPSIS);
-    }
+  Expect(Token::LPAREN, CHECK_OK);
+  int start_position = scanner()->location().beg_pos;
+  function_scope->set_start_position(start_position);
+  int num_parameters = ParseFormalParameterList(function_scope, &error_locs,
+                                                &is_rest, CHECK_OK);
+  Expect(Token::RPAREN, CHECK_OK);
+  int formals_end_position = scanner()->location().end_pos;
 
-    Identifier param_name =
-        ParseIdentifierOrStrictReservedWord(&is_strict_reserved, CHECK_OK);
-    if (!eval_args_loc.IsValid() && param_name.IsEvalOrArguments()) {
-      eval_args_loc = scanner()->location();
-    }
-    if (!undefined_loc.IsValid() && param_name.IsUndefined()) {
-      undefined_loc = scanner()->location();
-    }
-    if (!reserved_loc.IsValid() && is_strict_reserved) {
-      reserved_loc = scanner()->location();
-    }
-
-    int prev_value = scanner()->FindSymbol(&duplicate_finder, 1);
-
-    if (!dupe_loc.IsValid() && prev_value != 0) {
-      dupe_loc = scanner()->location();
-    }
-
-    if (arity_restriction == FunctionLiteral::SETTER_ARITY) break;
-    done = (peek() == Token::RPAREN);
-    if (!done) {
-      if (is_rest) {
-        ReportMessageAt(scanner()->peek_location(), "param_after_rest");
-        *ok = false;
-        return Expression::Default();
-      }
-      Expect(Token::COMMA, CHECK_OK);
-    }
-  }
-  Expect(Token::RPAREN, CHECK_OK);
+  CheckArityRestrictions(num_parameters, arity_restriction,
+                         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);
 
   // Validate name and parameter names. We can do this only after parsing the
   // function, since the function can declare itself strict.
   CheckFunctionName(language_mode(), kind, function_name,
                     name_is_strict_reserved, function_name_location, CHECK_OK);
   const bool use_strict_params = is_rest || IsConciseMethod(kind);
-  CheckFunctionParameterNames(language_mode(), use_strict_params, eval_args_loc,
-                              undefined_loc, dupe_loc, reserved_loc, CHECK_OK);
+  CheckFunctionParameterNames(language_mode(), use_strict_params, error_locs,
+                              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_call_location().IsValid()) {
       ReportMessageAt(function_name_location, "strong_super_call_missing",
                       kReferenceError);
@@ skipping 89 matching lines @@
 
   DCHECK(!spread_pos.IsValid());
 
   return Expression::Default();
 }
 
 #undef CHECK_OK
 
 
 } }  // v8::internal