bindings: Use Maybe APIs in toXXX() functions

Source/bindings/core/v8/V8Binding.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 146 matching lines @@
     static const unsigned numberOfValues = 65536; // 2^16
 };
 
 template <typename T>
 static inline T toSmallerInt(v8::Isolate* isolate, v8::Handle<v8::Value> value, IntegerConversionConfiguration configuration, const char* typeName, ExceptionState& exceptionState)
 {
     typedef IntTypeLimits<T> LimitsTrait;
 
     // Fast case. The value is already a 32-bit integer in the right range.
     if (value->IsInt32()) {
-        int32_t result = value->Int32Value();
+        int32_t result = value.As<v8::Int32>()->Value();
         if (result >= LimitsTrait::minValue && result <= LimitsTrait::maxValue)
             return static_cast<T>(result);
         if (configuration == EnforceRange) {
             exceptionState.throwTypeError("Value is outside the '" + String(typeName) + "' value range.");
             return 0;
         }
         if (configuration == Clamp)
             return clampTo<T>(result);
         result %= LimitsTrait::numberOfValues;
         return static_cast<T>(result > LimitsTrait::maxValue ? result - LimitsTrait::numberOfValues : result);
     }
 
     v8::Local<v8::Number> numberObject;
     if (value->IsNumber()) {
         numberObject = value.As<v8::Number>();
     } else {
         // Can the value be converted to a number?
         v8::TryCatch block(isolate);
-        numberObject = value->ToNumber(isolate);
-        if (block.HasCaught()) {
+        if (!v8Call(value->ToNumber(isolate->GetCurrentContext()), numberObject, block)) {
             exceptionState.rethrowV8Exception(block.Exception());
             return 0;
         }
     }
     ASSERT(!numberObject.IsEmpty());
 
     if (configuration == EnforceRange)
         return enforceRange(numberObject->Value(), LimitsTrait::minValue, LimitsTrait::maxValue, typeName, exceptionState);
 
     double numberValue = numberObject->Value();
@@ skipping 12 matching lines @@
     return static_cast<T>(numberValue > LimitsTrait::maxValue ? numberValue - LimitsTrait::numberOfValues : numberValue);
 }
 
 template <typename T>
 static inline T toSmallerUInt(v8::Isolate* isolate, v8::Handle<v8::Value> value, IntegerConversionConfiguration configuration, const char* typeName, ExceptionState& exceptionState)
 {
     typedef IntTypeLimits<T> LimitsTrait;
 
     // Fast case. The value is a 32-bit signed integer - possibly positive?
     if (value->IsInt32()) {
-        int32_t result = value->Int32Value();
+        int32_t result = value.As<v8::Int32>()->Value();
         if (result >= 0 && result <= LimitsTrait::maxValue)
             return static_cast<T>(result);
         if (configuration == EnforceRange) {
             exceptionState.throwTypeError("Value is outside the '" + String(typeName) + "' value range.");
             return 0;
         }
         if (configuration == Clamp)
             return clampTo<T>(result);
         return static_cast<T>(result);
     }
 
     v8::Local<v8::Number> numberObject;
     if (value->IsNumber()) {
         numberObject = value.As<v8::Number>();
     } else {
         // Can the value be converted to a number?
         v8::TryCatch block(isolate);
-        numberObject = value->ToNumber(isolate);
-        if (block.HasCaught()) {
+        if (!v8Call(value->ToNumber(isolate->GetCurrentContext()), numberObject, block)) {
             exceptionState.rethrowV8Exception(block.Exception());
             return 0;
         }
     }
     ASSERT(!numberObject.IsEmpty());
 
     if (configuration == EnforceRange)
         return enforceRange(numberObject->Value(), 0, LimitsTrait::maxValue, typeName, exceptionState);
 
     double numberValue = numberObject->Value();
@@ skipping 29 matching lines @@
 uint16_t toUInt16(v8::Isolate* isolate, v8::Handle<v8::Value> value, IntegerConversionConfiguration configuration, ExceptionState& exceptionState)
 {
     return toSmallerUInt<uint16_t>(isolate, value, configuration, "unsigned short", exceptionState);
 }
 
 int32_t toInt32Slow(v8::Isolate* isolate, v8::Handle<v8::Value> value, IntegerConversionConfiguration configuration, ExceptionState& exceptionState)
 {
     ASSERT(!value->IsInt32());
     // Can the value be converted to a number?
     v8::TryCatch block(isolate);
-    v8::Local<v8::Number> numberObject = value->ToNumber(isolate);
-    if (block.HasCaught()) {
+    v8::Local<v8::Number> numberObject;
+    if (!v8Call(value->ToNumber(isolate->GetCurrentContext()), numberObject, block)) {
         exceptionState.rethrowV8Exception(block.Exception());
         return 0;
     }
 
     ASSERT(!numberObject.IsEmpty());
 
     double numberValue = numberObject->Value();
     if (configuration == EnforceRange)
         return enforceRange(numberValue, kMinInt32, kMaxInt32, "long", exceptionState);
 
     if (std::isnan(numberValue))
         return 0;
 
     if (configuration == Clamp)
         return clampTo<int32_t>(numberValue);
 
     if (std::isinf(numberValue))
         return 0;
 
-    return numberObject->Int32Value();
+    int32_t result;
+    if (!v8Call(numberObject->Int32Value(isolate->GetCurrentContext()), result, block)) {
+        exceptionState.rethrowV8Exception(block.Exception());

[Jens Widell, 2015/03/25 11:11:15]

Technically, this call can't fail, since numberObject is known to be a number.
It's really just performing a double->int conversion (according to the rules of
ECMA-262).

We might want to replace the error handling with some variation of assertions.

[haraken, 2015/03/25 11:53:44]

In practice this call won't fail, but conceptually there is no guarantee that
Int32Value() does something that can receive a worker termination signal and
throw an exception. Personally I don't want to put too much assumptions on what
V8 APIs will do, so I'd slightly prefer having the rethrowV8Exception in these
non-trivial cases. For the same reason, I might want to limit the places we use
ToLocalChecked. (ToLocalChecked means that we're assuming that the V8 API never
throws an exception, but this kind of assumption sounds a bit too implicit to
me.)

+        return 0;
+    }
+    return result;
 }
 
 uint32_t toUInt32Slow(v8::Isolate* isolate, v8::Handle<v8::Value> value, IntegerConversionConfiguration configuration, ExceptionState& exceptionState)
 {
     ASSERT(!value->IsUint32());
     if (value->IsInt32()) {
         ASSERT(configuration != NormalConversion);
-        int32_t result = value->Int32Value();
+        int32_t result = value.As<v8::Int32>()->Value();
         if (result >= 0)
             return result;
         if (configuration == EnforceRange) {
             exceptionState.throwTypeError("Value is outside the 'unsigned long' value range.");
             return 0;
         }
         ASSERT(configuration == Clamp);
         return clampTo<uint32_t>(result);
     }
 
     // Can the value be converted to a number?
     v8::TryCatch block(isolate);
-    v8::Local<v8::Number> numberObject = value->ToNumber(isolate);
-    if (block.HasCaught()) {
+    v8::Local<v8::Number> numberObject;
+    if (!v8Call(value->ToNumber(isolate->GetCurrentContext()), numberObject, block)) {
         exceptionState.rethrowV8Exception(block.Exception());
         return 0;
     }
     ASSERT(!numberObject.IsEmpty());
 
     if (configuration == EnforceRange)
         return enforceRange(numberObject->Value(), 0, kMaxUInt32, "unsigned long", exceptionState);
 
     double numberValue = numberObject->Value();
 
     if (std::isnan(numberValue))
         return 0;
 
     if (configuration == Clamp)
         return clampTo<uint32_t>(numberValue);
 
     if (std::isinf(numberValue))
         return 0;
 
-    return numberObject->Uint32Value();
+    uint32_t result;
+    if (!v8Call(numberObject->Uint32Value(isolate->GetCurrentContext()), result, block)) {
+        exceptionState.rethrowV8Exception(block.Exception());

[Jens Widell, 2015/03/25 11:11:15]

Same here.

+        return 0;
+    }
+    return result;
 }
 
 int64_t toInt64Slow(v8::Isolate* isolate, v8::Handle<v8::Value> value, IntegerConversionConfiguration configuration, ExceptionState& exceptionState)
 {
     ASSERT(!value->IsInt32());
 
     v8::Local<v8::Number> numberObject;
     // Can the value be converted to a number?
     v8::TryCatch block(isolate);
-    numberObject = value->ToNumber(isolate);
-    if (block.HasCaught()) {
+    if (!v8Call(value->ToNumber(isolate->GetCurrentContext()), numberObject, block)) {
         exceptionState.rethrowV8Exception(block.Exception());
         return 0;
     }
     ASSERT(!numberObject.IsEmpty());
 
     double numberValue = numberObject->Value();
 
     if (configuration == EnforceRange)
         return enforceRange(numberValue, -kJSMaxInteger, kJSMaxInteger, "long long", exceptionState);
 
     if (std::isnan(numberValue) || std::isinf(numberValue))
         return 0;
 
     // NaNs and +/-Infinity should be 0, otherwise modulo 2^64.
     unsigned long long integer;
     doubleToInteger(numberValue, integer);
     return integer;
 }
 
 uint64_t toUInt64Slow(v8::Isolate* isolate, v8::Handle<v8::Value> value, IntegerConversionConfiguration configuration, ExceptionState& exceptionState)
 {
     ASSERT(!value->IsUint32());
     if (value->IsInt32()) {
         ASSERT(configuration != NormalConversion);
-        int32_t result = value->Int32Value();
+        int32_t result = value.As<v8::Int32>()->Value();
         if (result >= 0)
             return result;
         if (configuration == EnforceRange) {
             exceptionState.throwTypeError("Value is outside the 'unsigned long long' value range.");
             return 0;
         }
         ASSERT(configuration == Clamp);
         return clampTo<uint64_t>(result);
     }
 
     v8::Local<v8::Number> numberObject;
     // Can the value be converted to a number?
     v8::TryCatch block(isolate);
-    numberObject = value->ToNumber(isolate);
-    if (block.HasCaught()) {
+    if (!v8Call(value->ToNumber(isolate->GetCurrentContext()), numberObject, block)) {
         exceptionState.rethrowV8Exception(block.Exception());
         return 0;
     }
     ASSERT(!numberObject.IsEmpty());
 
     double numberValue = numberObject->Value();
 
     if (configuration == EnforceRange)
         return enforceRange(numberValue, 0, kJSMaxInteger, "unsigned long long", exceptionState);
 
@@ skipping 21 matching lines @@
         exceptionState.throwTypeError("The provided float value is non-finite.");
         return 0;
     }
     return numberValue;
 }
 
 double toDoubleSlow(v8::Isolate* isolate, v8::Handle<v8::Value> value, ExceptionState& exceptionState)
 {
     ASSERT(!value->IsNumber());
     v8::TryCatch block(isolate);
-    double doubleValue = value->NumberValue();
-    if (block.HasCaught()) {
+    double doubleValue;
+    if (!v8Call(value->NumberValue(isolate->GetCurrentContext()), doubleValue, block)) {
         exceptionState.rethrowV8Exception(block.Exception());
         return 0;
     }
     return doubleValue;
 }
 
 double toRestrictedDouble(v8::Isolate* isolate, v8::Handle<v8::Value> value, ExceptionState& exceptionState)
 {
     double numberValue = toDouble(isolate, value, exceptionState);
     if (exceptionState.hadException())
@@ skipping 14 matching lines @@
     // From the Web IDL spec: http://heycam.github.io/webidl/#es-ByteString
     if (value.IsEmpty())
         return String();
 
     // 1. Let x be ToString(v)
     v8::Local<v8::String> stringObject;
     if (value->IsString()) {
         stringObject = value.As<v8::String>();
     } else {
         v8::TryCatch block(isolate);
-        stringObject = value->ToString(isolate);
-        if (block.HasCaught()) {
+        if (!v8Call(value->ToString(isolate->GetCurrentContext()), stringObject, block)) {
             exceptionState.rethrowV8Exception(block.Exception());
             return String();
         }
     }
 
     String x = toCoreString(stringObject);
 
     // 2. If the value of any element of x is greater than 255, then throw a TypeError.
     if (!x.containsOnlyLatin1()) {
         exceptionState.throwTypeError("Value is not a valid ByteString.");
@@ skipping 113 matching lines @@
 {
     // http://heycam.github.io/webidl/#es-USVString
     if (value.IsEmpty())
         return String();
 
     v8::Local<v8::String> stringObject;
     if (value->IsString()) {
         stringObject = value.As<v8::String>();
     } else {
         v8::TryCatch block(isolate);
-        stringObject = value->ToString(isolate);
-        if (block.HasCaught()) {
+        if (!v8Call(value->ToString(isolate->GetCurrentContext()), stringObject, block)) {
             exceptionState.rethrowV8Exception(block.Exception());
             return String();
         }
     }
 
     // USVString is identical to DOMString except that "convert a
     // DOMString to a sequence of Unicode characters" is used subsequently
     // when converting to an IDL value
     String x = toCoreString(stringObject);
     return replaceUnmatchedSurrogates(x);
@@ skipping 315 matching lines @@
     v8::Local<v8::Value> data = info.Data();
     ASSERT(data->IsExternal());
     V8PerContextData* perContextData = V8PerContextData::from(info.Holder()->CreationContext());
     if (!perContextData)
         return;
     v8SetReturnValue(info, perContextData->constructorForType(WrapperTypeInfo::unwrap(data)));
     TRACE_EVENT_SET_SAMPLING_STATE("v8", "V8Execution");
 }
 
 } // namespace blink