given the following object :
----------------------------------------------
function SomeObject() {}
SomeObject.prototype.exec = function() {
var local = this.someField;
}
----------------------------------------------
i create an 'instance', set a field and call the exec method :
----------------------------------------------
var someField = "global field value";
var anInstance = new SomeObject();
anInstance.someField = "instance field value";
anInstance.exec();
----------------------------------------------
then the local variable 'local' in the exec() method is assigned the value
of the global 'someField' variable instead of the instance field value.
the problem seems to be in the ScriptRuntime.callOrNewSpecial() method,
which is called, because the parser treats the name 'exec' specially. in
this method the exec() method gets called with
return call(cx, fun, thisArg, args, scope);
where the 'thisArg' parameter really is the global this value instead of
the dynamic this value, which is in the jsThis variable and which would be
the one needed...
is it legitimate to replace the above call in callOrNewSpecial() with the
following line :
return call(cx, fun, jsThis, args, scope);
this seems to only happen for methods named 'exec', which are identified as
special in the NodeTransformer.isSpecialCallName() method.
any help is appreciated. thank you very much for your time.
kind regards,
felix
The attached patch adds support for debugging eval and Function code transparently. It changes omj.NativeGlobal and omj.BaseFunction to embed line number of origin of eval and Function scripts into source name and pass 1 as base line for script code. In this way a debugger implementation can treat eval and Function code in the same way as scripts loaded from some url while giving more information about error location in case of an error in eval code as the error source would contain both line number of eval origin and line number in eval code itself.
I chose to embed line numbers via patterns like
sourcefile#<line-number>(eval)
sourcefile#<line-number>(Function)
just to be able to to pass the constructed name to URL constructor if the original sourcefile is a valid URL but it is pretty arbitrary.
I have noticed that attempting to call a java method like this:
public void foo(String foo, Serializable bar)
{
// un-important details
}
from script using foo("foo", "bar"); fails because the second argument
is not deemed coercable to Serializable. A preliminary look at the
coercion code shows that no check is made in this case with
isAssignableFrom().
The to type is only tested against StringClass and ObjectClass (non
primitive case).
(See NativeJavaObject.getConversionWeight())
I attach the patch to move away setting/quering for breakpoints from the Rhino core to application as a debugger implementation can check if a particular line has a breakpoint or not. The changes to omj/tools/debugger takes more then few lines I initially thought but they are mostly caused by refactoring to implement different view to set/query breakpoints.
The patch replaces getLineNumbers, placeBreakpoint and removeBreakpoint in DebuggableScript by getFirstLine, getEndLine and getInstructionLines where the last function fills a boolean array to indicate which script lines can ever occur in DebugFrame.onLineChange. These are read-only functions so InterpeterData are never mdofied by the debugger.
omj/tools/debugger/Main uses this information to check whether it is possible to place breakpoint at a particular line, and if possible, it sets to true entry at the boolean breakpoint array. In this way testing for break in onLineChange is simple and fast as it just needs to check if breakpoint array holds true at the given line number position.
