Lazily format LanguageError messages (fix issue 15069).

runtime/vm/object.h

 // 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.
 
 #ifndef VM_OBJECT_H_
 #define VM_OBJECT_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ skipping 3742 matching lines @@
   virtual const char* ToErrorCString() const;
 
  private:
   HEAP_OBJECT_IMPLEMENTATION(Error, Object);
 };
 
 
 class ApiError : public Error {
  public:
   RawString* message() const { return raw_ptr()->message_; }
-  static intptr_t message_offset() {
-    return OFFSET_OF(RawApiError, message_);
-  }
 
   static intptr_t InstanceSize() {
     return RoundedAllocationSize(sizeof(RawApiError));
   }
 
   static RawApiError* New(const String& message,
                           Heap::Space space = Heap::kNew);
 
   virtual const char* ToErrorCString() const;
 
  private:
   void set_message(const String& message) const;
 
   static RawApiError* New();
 
   FINAL_HEAP_OBJECT_IMPLEMENTATION(ApiError, Error);
   friend class Class;
 };
 
 
 class LanguageError : public Error {
  public:
-  RawString* message() const { return raw_ptr()->message_; }
-  static intptr_t message_offset() {
-    return OFFSET_OF(RawLanguageError, message_);
-  }
+  enum Kind {
+    kWarning,
+    kError,
+    kMalformedType,
+    kMalboundedType,
+  };
+
+  // Build, cache, and return formatted message.
+  RawString* FormatMessage() const;
 
   static intptr_t InstanceSize() {
     return RoundedAllocationSize(sizeof(RawLanguageError));
   }
 
-  static RawLanguageError* New(const String& message,
+  // A null script means no source and a negative token_pos means no position.
+  static RawLanguageError* New(const Error& prev_error,
+                               const Script& script,
+                               intptr_t token_pos,
+                               Kind kind,
+                               const String& message,
+                               Heap::Space space = Heap::kNew);

[Ivan Posva, 2013/11/15 04:42:13]

I find it a bit strange that the space parameter trades places with the
message/format between this method and the the two below. Maybe we should have
the message always after the space parameter.

[regis, 2013/11/15 18:27:38]

The space parameter is optional in most New calls and therefore has to be last.
This is not possible with vargs.
So I could switch the order and make it required, but better still, I can get
rid of this function variant.

+
+  static RawLanguageError* NewFormatted(const Error& prev_error,
+                                        const Script& script,
+                                        intptr_t token_pos,
+                                        Kind kind,
+                                        Heap::Space space,
+                                        const char* format, ...)
+    PRINTF_ATTRIBUTE(6, 7);
+
+  static RawLanguageError* NewFormattedV(const Error& prev_error,
+                                         const Script& script,
+                                         intptr_t token_pos,
+                                         Kind kind,
+                                         Heap::Space space,
+                                         const char* format, va_list args);
+
+  static RawLanguageError* New(const String& formatted_message,
                                Heap::Space space = Heap::kNew);
 
   virtual const char* ToErrorCString() const;
 
  private:
-  void set_message(const String& message) const;
+  RawError* previous_error() const {
+    return raw_ptr()->previous_error_;
+  }
+  void set_previous_error(const Error& value) const;
+
+  RawScript* script() const { return raw_ptr()->script_; }
+  void set_script(const Script& value) const;
+
+  intptr_t token_pos() const { return raw_ptr()->token_pos_; }
+  void set_token_pos(intptr_t value) const;
+
+  Kind kind() const { return static_cast<Kind>(raw_ptr()->kind_); }
+  void set_kind(uint8_t value) const;
+
+  RawString* message() const { return raw_ptr()->message_; }
+  void set_message(const String& value) const;
+
+  RawString* formatted_message() const { return raw_ptr()->formatted_message_; }
+  void set_formatted_message(const String& value) const;
 
   static RawLanguageError* New();
 
   FINAL_HEAP_OBJECT_IMPLEMENTATION(LanguageError, Error);
   friend class Class;
 };
 
 
 class UnhandledException : public Error {
  public:
@@ skipping 22 matching lines @@
   void set_stacktrace(const Instance& stacktrace) const;
 
   FINAL_HEAP_OBJECT_IMPLEMENTATION(UnhandledException, Error);
   friend class Class;
 };
 
 
 class UnwindError : public Error {
  public:
   RawString* message() const { return raw_ptr()->message_; }
-  static intptr_t message_offset() {
-    return OFFSET_OF(RawUnwindError, message_);
-  }
 
   static intptr_t InstanceSize() {
     return RoundedAllocationSize(sizeof(RawUnwindError));
   }
 
   static RawUnwindError* New(const String& message,
                              Heap::Space space = Heap::kNew);
 
   virtual const char* ToErrorCString() const;
 
@@ skipping 2531 matching lines @@
 
 
 RawObject* MegamorphicCache::GetTargetFunction(const Array& array,
                                                intptr_t index) {
   return array.At((index * kEntryLength) + kTargetFunctionIndex);
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_