[parser] Skipping inner funcs: produce the same scopes / variables for parameters (part 2).

This CL covers simple ("simple") rest param cases.

BUG=v8:5516
R=vogelheim@chromium.org

Change-Id: I254c2eb81d759eb2ea2a3d5e7c46bcdc2ccef707
Reviewed-on: https://chromium-review.googlesource.com/440984Reviewed-by: Daniel Vogelheim <vogelheim@chromium.org>
Commit-Queue: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43106}

src/parsing/preparser.cc

@@ -133,6 +133,7 @@ PreParser::PreParseResult PreParser::PreParseFunction(
         !classifier()->is_valid_formal_parameter_list_without_duplicates();
   }
 
+  Expect(Token::LBRACE, CHECK_OK_VALUE(kPreParseSuccess));
   DeclarationScope* inner_scope = function_scope;
   LazyParsingResult result;
 
@@ -143,18 +144,18 @@ PreParser::PreParseResult PreParser::PreParseFunction(
 
   {
     BlockState block_state(&scope_state_, inner_scope);
-    Expect(Token::LBRACE, CHECK_OK_VALUE(kPreParseSuccess));
     result = ParseStatementListAndLogFunction(
         &formals, has_duplicate_parameters, may_abort, ok);
   }
 
-  if (!formals.is_simple) {
-    SetLanguageMode(function_scope, inner_scope->language_mode());
-    inner_scope->set_end_position(scanner()->location().end_pos);
+  if (is_sloppy(inner_scope->language_mode())) {
+    inner_scope->HoistSloppyBlockFunctions(nullptr);
   }
 
-  if (is_sloppy(function_scope->language_mode())) {
-    function_scope->HoistSloppyBlockFunctions(nullptr);
+  if (!formals.is_simple) {
+    SetLanguageMode(function_scope, inner_scope->language_mode());
+    inner_scope->set_end_position(scanner()->peek_location().end_pos);
+    inner_scope->FinalizeBlockScope();
   }
 
   if (!IsArrowFunction(kind) && track_unresolved_variables_) {

test/cctest/parsing/test-preparser.cc

@@ -20,6 +20,9 @@ TEST(PreParserScopeAnalysis) {
   i::HandleScope scope(isolate);
   LocalContext env;
 
+  // FIXME(marja): Add tests where the test cases are deeper (in a second-level
+  // inner function or second-level inner arrow function). Remove redundant test
+  // cases.
   const char* prefix = "(function outer() { ";
   const char* suffix = " })();";
   int prefix_len = Utf8LengthHelper(prefix);
@@ -299,9 +302,18 @@ TEST(PreParserScopeAnalysis) {
       {"var1, var1", "function f1() { var1; }"},
       {"var1, var1", "function f1() { var1 = 9; }"},
 
-      // FIXME(marja): destructuring parameters, rest parameter, default
-      // parameters, shadowing parameters, default parameters referring to other
-      // parameters, arguments parameter, eval in default parameter.
+      // Rest parameter.
+      {"...var2", ""},
+      {"...var2", "var2;"},
+      {"...var2", "var2 = 9;"},
+      {"...var2", "function f1() { var2; }"},
+      {"...var2", "function f1() { var2 = 9; }"},
+
+      // FIXME(marja): destructuring parameters, default parameters, shadowing
+      // parameters, default parameters referring to other parameters, arguments
+      // parameter, eval in default parameter, params and locals, multiple
+      // params, many params and rest, destructuring rest, rest with default
+      // value, locals shadowing params.
   };
 
   for (unsigned i = 0; i < arraysize(inners); ++i) {