Fix for issue 7089 (Symbols::New was not quite working correctly

vm/symbols.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/symbols.h"
 
 #include "vm/isolate.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/raw_object.h"
@@ skipping 79 matching lines @@
 void Symbols::Add(const Array& symbol_table, const String& str) {
   // Should only be run by the vm isolate.
   ASSERT(Isolate::Current() == Dart::vm_isolate());
   intptr_t hash = str.Hash();
   intptr_t index = FindIndex(symbol_table, str, 0, str.Length(), hash);
   ASSERT(symbol_table.At(index) == String::null());
   InsertIntoSymbolTable(symbol_table, str, index);
 }
 
 
-RawString* Symbols::New(const char* str) {
-  ASSERT(str != NULL);
+RawString* Symbols::New(const char* cstr) {
+  ASSERT(cstr != NULL);
+  intptr_t array_len = strlen(cstr);
+  const uint8_t* utf8_array = reinterpret_cast<const uint8_t*>(cstr);
+  return Symbols::New(utf8_array, array_len);
+}
+
+
+RawString* Symbols::New(const uint8_t* utf8_array, intptr_t array_len) {
+  if (array_len == 0 || utf8_array == NULL) {
+    return NewSymbol(reinterpret_cast<uint8_t*>(NULL), 0);
+  }
   Utf8::Type type;
-  intptr_t str_len = strlen(str);
-  const uint8_t* utf8_array = reinterpret_cast<const uint8_t*>(str);
-  intptr_t len = Utf8::CodeUnitCount(utf8_array, str_len, &type);
+  intptr_t len = Utf8::CodeUnitCount(utf8_array, array_len, &type);
+  ASSERT(len != 0);
   Zone* zone = Isolate::Current()->current_zone();
-  if (len == 0) {
-    return Symbols::New(reinterpret_cast<uint8_t*>(NULL), 0);
-  }
   if (type == Utf8::kLatin1) {
     uint8_t* characters = zone->Alloc<uint8_t>(len);
-    Utf8::DecodeToLatin1(utf8_array, str_len, characters, len);
-    return New(characters, len);
+    Utf8::DecodeToLatin1(utf8_array, array_len, characters, len);
+    return NewSymbol(characters, len);
   }
   ASSERT((type == Utf8::kBMP) || (type == Utf8::kSupplementary));
   uint16_t* characters = zone->Alloc<uint16_t>(len);
-  Utf8::DecodeToUTF16(utf8_array, str_len, characters, len);
-  return New(characters, len);
+  Utf8::DecodeToUTF16(utf8_array, array_len, characters, len);
+  return NewSymbol(characters, len);
+}
+
+
+RawString* Symbols::New(const uint16_t* characters, intptr_t len) {
+  return NewSymbol(characters, len);
+}
+
+
+RawString* Symbols::New(const int32_t* characters, intptr_t len) {
+  return NewSymbol(characters, len);
 }
 
 
 template<typename T>
-RawString* Symbols::New(const T* characters, intptr_t len) {
+RawString* Symbols::NewSymbol(const T* characters, intptr_t len) {
   Isolate* isolate = Isolate::Current();
   String& symbol = String::Handle(isolate, String::null());
   Array& symbol_table = Array::Handle(isolate, Array::null());
 
   // Calculate the String hash for this sequence of characters.
   intptr_t hash = String::Hash(characters, len);
 
   // First check if a symbol exists in the vm isolate for these characters.
   symbol_table = Dart::vm_isolate()->object_store()->symbol_table();
   intptr_t index = FindIndex(symbol_table, characters, len, hash);
   symbol ^= symbol_table.At(index);
   if (symbol.IsNull()) {
     // Now try in the symbol table of the current isolate.
     symbol_table = isolate->object_store()->symbol_table();
     index = FindIndex(symbol_table, characters, len, hash);
     // Since we leave enough room in the table to guarantee, that we find an
     // empty spot, index is the insertion point if symbol is null.
     symbol ^= symbol_table.At(index);
     if (symbol.IsNull()) {
       // Allocate new result string.
       symbol = String::New(characters, len, Heap::kOld);
       symbol.SetHash(hash);  // Remember the calculated hash value.
       InsertIntoSymbolTable(symbol_table, symbol, index);
     }
   }
   ASSERT(symbol.IsSymbol());
   return symbol.raw();
 }
 
-template RawString* Symbols::New(const uint8_t* characters, intptr_t len);
-template RawString* Symbols::New(const uint16_t* characters, intptr_t len);
-template RawString* Symbols::New(const int32_t* characters, intptr_t len);
+
+template RawString* Symbols::NewSymbol(const uint8_t* characters,
+                                       intptr_t len);
+template RawString* Symbols::NewSymbol(const uint16_t* characters,
+                                       intptr_t len);
+template RawString* Symbols::NewSymbol(const int32_t* characters,
+                                       intptr_t len);
 
 
 RawString* Symbols::New(const String& str) {
   if (str.IsSymbol()) {
     return str.raw();
   }
   return New(str, 0, str.Length());
 }
 
 
@@ skipping 157 matching lines @@
 }
 
 
 RawObject* Symbols::GetVMSymbol(intptr_t object_id) {
   ASSERT(IsVMSymbolId(object_id));
   intptr_t i = (object_id - kMaxPredefinedObjectIds);
   return (i > 0 && i < Symbols::kMaxId) ? predefined_[i] : Object::null();
 }
 
 }  // namespace dart