Sounds like this conversion might be being done in the wrong place, it doesn't feel like this should be the responsibility of this method since "undefined" is a valid return value from any JavaScript call.
On Wed, Dec 22, 2010 at 4:41 PM, Yury Semikhatsky <[email protected]> wrote: > > > On Wed, Dec 22, 2010 at 7:22 PM, Tom Rathbone <[email protected]> > wrote: >> >> From my experiments calling executeScriptAndReturnValue "function >> foo() { } foo();" will also return an empty handle meaning that this >> can't reliably be used to detect errors. Is there another way to >> distinguish non values from errors? > > I see, the problem is that 'undefined' value is converted into an empty > ScriptValue in ScriptController::evaluate: > http://codesearch.google.com/codesearch/p?hl=en#OAMlx_jo-ck/src/third_party/WebKit/WebCore/bindings/v8/ScriptController.cpp&q=::executeScriptAndReturnValue%5C(&gs=cpp:WebCore::ScriptController::executeScript(const%2520WebCore::ScriptSourceCode%2520&,%2520enum%2520ShouldAllowXSS)@chrome/trunk/src/third_party/WebKit/WebCore/bindings/v8/ScriptController.h%257Cdecl&gsn=executeScript&d=5&l=260 > Not sure what this conversion is used for. > Yury > > >> >> On Wed, Dec 22, 2010 at 2:35 PM, Yury Semikhatsky <[email protected]> >> wrote: >> > Hi Tom, >> > In case of uncaught JS exception returned v8::Handle will always be >> > empty >> > (v8::Handle<v8::Value>::IsEmpty() will return true) while in case of >> > successful >> > evaluation the result is always non-empty. Also uncaught JS exception >> > will >> > be >> > reported to the console object(see Console.cpp) which will propagate >> > them >> > to >> > InspectorController and ChromeClient. >> > Thanks, >> > Yury >> > >> > On Wed, Dec 22, 2010 at 12:58 PM, Tom Rathbone <[email protected]> >> > wrote: >> >> >> >> Hi Guys, >> >> >> >> I was wondering if it would be possible to expose v8 exceptions >> >> through WebFrameImpl::executeScriptAndReturnValue and >> >> ScriptController::executeScript, perhaps as an output reference >> >> argument. >> >> >> >> The effected methods would be: >> >> >> >> v8::Handle<v8::Value> WebFrameImpl::executeScriptAndReturnValue(const >> >> WebScriptSource& source) >> >> ScriptValue ScriptController::executeScript(const ScriptSourceCode& >> >> sourceCode, ShouldAllowXSS shouldAllowXSS) >> >> ScriptValue ScriptController::evaluate(const ScriptSourceCode& >> >> sourceCode, ShouldAllowXSS shouldAllowXSS) >> >> v8::Local<v8::Value> V8Proxy::evaluate(const ScriptSourceCode& source, >> >> Node* node) >> >> >> >> If I've read the source correctly V8 exceptions are caught in >> >> V8Proxy::evaluate and swallowed. This means clients calling >> >> executeScriptAndReturnValue have no easy way of determining what went >> >> wrong or of responding to script errors. >> >> >> >> Maybe... >> >> >> >> v8::Handle<v8::Value> WebFrameImpl::executeScriptAndReturnValue(const >> >> WebScriptSource& source, bool& exceptionReturned) >> >> >> >> If others think these changes are worthwhile then I'll have a go at >> >> crafting a patch. >> >> >> >> Thanks, >> >> >> >> Tom. >> >> _______________________________________________ >> >> webkit-dev mailing list >> >> [email protected] >> >> http://lists.webkit.org/mailman/listinfo.cgi/webkit-dev >> > >> > > > _______________________________________________ webkit-dev mailing list [email protected] http://lists.webkit.org/mailman/listinfo.cgi/webkit-dev
