Propagate switch statement value for 'eval'

src/parser.cc

Index: src/parser.cc
diff --git a/src/parser.cc b/src/parser.cc
index 3f635c70df275ea837606aa81354f6daea36a882..048216ca7a323a69185a66f252b837a34fe8a6c0 100644
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -2990,7 +2990,7 @@ Statement* Parser::ParseSwitchStatement(ZoneList<const AstRawString*>* labels,
   // }
 
   Block* switch_block =
-      factory()->NewBlock(NULL, 2, true, RelocInfo::kNoPosition);
+      factory()->NewBlock(NULL, 2, false, RelocInfo::kNoPosition);

[adamk, 2015/08/28 22:03:20]

We really ought to change this param to an enum so the callsites are clearer,
but that's a cleanup for a future CL.

   int switch_pos = peek_position();
 
   Expect(Token::SWITCH, CHECK_OK);
@@ -3007,8 +3007,17 @@ Statement* Parser::ParseSwitchStatement(ZoneList<const AstRawString*>* labels,
       factory()->NewExpressionStatement(tag_assign, RelocInfo::kNoPosition);
   switch_block->AddStatement(tag_statement, zone());
 
+  // make statement: undefined;
+  // This is needed so the tag isn't returned as the value, in case the switch
+  // statements don't have a value.
+  switch_block->AddStatement(
+      factory()->NewExpressionStatement(
+          factory()->NewUndefinedLiteral(RelocInfo::kNoPosition),
+          RelocInfo::kNoPosition),
+      zone());
+
   Block* cases_block =
-      factory()->NewBlock(NULL, 1, true, RelocInfo::kNoPosition);
+      factory()->NewBlock(NULL, 1, false, RelocInfo::kNoPosition);
   Scope* cases_scope = NewScope(scope_, BLOCK_SCOPE);
 
   SwitchStatement* switch_statement =