Create a character stream and hook it up to the parse info

src/parsing/parser.cc

 // Copyright 2012 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 "src/parsing/parser.h"
 
 #include <memory>
 
 #include "src/api.h"
 #include "src/ast/ast.h"
@@ skipping 28 matching lines @@
     data_ = copy;
     AcquireDataOwnership();
   }
 }
 
 ParseInfo::ParseInfo(Zone* zone)
     : zone_(zone),
       flags_(0),
       source_stream_(nullptr),
       source_stream_encoding_(ScriptCompiler::StreamedSource::ONE_BYTE),
+      character_stream_(nullptr),
       extension_(nullptr),
       compile_options_(ScriptCompiler::kNoCompileOptions),
       script_scope_(nullptr),
       unicode_cache_(nullptr),
       stack_limit_(0),
       hash_seed_(0),
       isolate_(nullptr),
       cached_data_(nullptr),
       ast_value_factory_(nullptr),
       literal_(nullptr),
@@ skipping 762 matching lines @@
       original_scope_(NULL),
       target_stack_(NULL),
       compile_options_(info->compile_options()),
       cached_parse_data_(NULL),
       total_preparse_skipped_(0),
       pre_parse_timer_(NULL),
       parsing_on_main_thread_(true) {
   // Even though we were passed ParseInfo, we should not store it in
   // Parser - this makes sure that Isolate is not accidentally accessed via
   // ParseInfo during background parsing.
-  DCHECK(!info->script().is_null() || info->source_stream() != NULL);
+  DCHECK(!info->script().is_null() || info->source_stream() != nullptr ||
+         info->character_stream() != nullptr);
   set_allow_lazy(info->allow_lazy_parsing());
   set_allow_natives(FLAG_allow_natives_syntax || info->is_native());
   set_allow_tailcalls(FLAG_harmony_tailcalls && !info->is_native() &&
                       info->isolate()->is_tail_call_elimination_enabled());
   set_allow_harmony_do_expressions(FLAG_harmony_do_expressions);
   set_allow_harmony_for_in(FLAG_harmony_for_in);
   set_allow_harmony_function_sent(FLAG_harmony_function_sent);
   set_allow_harmony_restrictive_declarations(
       FLAG_harmony_restrictive_declarations);
   set_allow_harmony_exponentiation_operator(
@@ skipping 4627 matching lines @@
 void Parser::ParseOnBackground(ParseInfo* info) {
   parsing_on_main_thread_ = false;
 
   DCHECK(info->literal() == NULL);
   FunctionLiteral* result = NULL;
   fni_ = new (zone()) FuncNameInferrer(ast_value_factory(), zone());
 
   CompleteParserRecorder recorder;
   if (produce_cached_parse_data()) log_ = &recorder;
 
-  DCHECK(info->source_stream() != NULL);
-  ExternalStreamingStream stream(info->source_stream(),
-                                 info->source_stream_encoding());
-  scanner_.Initialize(&stream);
+  std::unique_ptr<Utf16CharacterStream> stream;
+  Utf16CharacterStream* stream_ptr;
+  if (info->character_stream()) {
+    DCHECK(info->source_stream() == nullptr);
+    stream_ptr = info->character_stream();
+  } else {
+    DCHECK(info->character_stream() == nullptr);
+    stream.reset(new ExternalStreamingStream(info->source_stream(),
+                                             info->source_stream_encoding()));
+    stream_ptr = stream.get();
+  }
+  scanner_.Initialize(stream_ptr);
   DCHECK(info->context().is_null() || info->context()->IsNativeContext());
 
   // When streaming, we don't know the length of the source until we have parsed
   // it. The raw data can be UTF-8, so we wouldn't know the source length until
   // we have decoded it anyway even if we knew the raw data length (which we
   // don't). We work around this by storing all the scopes which need their end
   // position set at the end of the script (the top scope and possible eval
   // scopes) and set their end position after we know the script length.
   result = DoParseProgram(info);
 
@@ skipping 1607 matching lines @@
   node->Print(Isolate::Current());
 }
 #endif  // DEBUG
 
 #undef CHECK_OK
 #undef CHECK_OK_VOID
 #undef CHECK_FAILED
 
 }  // namespace internal
 }  // namespace v8