public void JsCanBeDebugged()
{
string fibonacci = @"
function fibonacci(num){
var a = 1, b = 0, temp;
while (num >= 0){
temp = a;
a = a + b;
b = temp;
num--;
}
return b;
};
fibonacci(50);
";
using (var runtimeHandle = Engine.JsCreateRuntime(JavaScriptRuntimeAttributes.None, null))
{
using (var contextHandle = Engine.JsCreateContext(runtimeHandle))
{
Engine.JsSetCurrentContext(contextHandle);
//Get the JSON.stringify function for later...
var globalObjectHandle = Engine.JsGetGlobalObject();
var jsonPropertyHandle = Engine.JsCreatePropertyId("JSON", (ulong)"JSON".Length);
var stringifyPropertyHandle = Engine.JsCreatePropertyId("stringify", (ulong)"stringify".Length);
var jsonObjectHandle = Engine.JsGetProperty(globalObjectHandle, jsonPropertyHandle);
var fnStringifyHandle = Engine.JsGetProperty(jsonObjectHandle, stringifyPropertyHandle);
bool firstLineHit = false;
string fibonacciFunctionPosition = "";
string firstFrameProperties = "";
string firstFrameChildren = "";
string firstStackObjectName = "";
var numDecrementing = new List <int>();
int calledCount = 0;
//Callback that is run for each breakpoint.
JavaScriptDiagDebugEventCallback callback = (JavaScriptDiagDebugEventType eventType, IntPtr eventData, IntPtr callbackState) =>
{
if (eventType == JavaScriptDiagDebugEventType.JsDiagDebugEventRuntimeException)
{
//When a problem comes along you must skip it
//Before the cream sits out too long you must skip it
Engine.JsDiagSetStepType(JavaScriptDiagStepType.StepIn);
}
var stackTrace = Engine.JsDiagGetStackTrace();
//Get the first frame in the stack.
var ix = Engine.JsIntToNumber(0);
var objFrameHandle = Engine.JsGetIndexedProperty(stackTrace, ix);
//Get the line and the source
var linePropertyHandle = Engine.JsCreatePropertyId("line", (ulong)"line".Length);
var lineHandle = Engine.JsGetProperty(objFrameHandle, linePropertyHandle);
var line = Engine.JsNumberToInt(lineHandle);
var functionHandlePropertyHandle = Engine.JsCreatePropertyId("functionHandle", (ulong)"functionHandle".Length);
var functionHandleHandle = Engine.JsGetProperty(objFrameHandle, functionHandlePropertyHandle);
var functionHandle = Engine.JsNumberToInt(functionHandleHandle);
var sourceTextPropertyHandle = Engine.JsCreatePropertyId("sourceText", (ulong)"sourceText".Length);
var sourceTextHandle = Engine.JsGetProperty(objFrameHandle, sourceTextPropertyHandle);
var sourceLength = Engine.JsGetStringLength(sourceTextHandle);
byte[] buffer = new byte[sourceLength];
var written = Engine.JsCopyString(sourceTextHandle, buffer, (ulong)sourceLength);
var sourceText = Encoding.UTF8.GetString(buffer);
//If we hit the first line...
if (sourceText == "fibonacci(50)")
{
firstLineHit = true;
//Get some information about the stack frame.
var stackProperties = Engine.JsDiagGetStackProperties(0);
//Stringify the propertyHandle.
var stringifiedPropertyHandle = Engine.JsCallFunction(fnStringifyHandle, new IntPtr[] { globalObjectHandle.DangerousGetHandle(), stackProperties.DangerousGetHandle() }, 2);
var stringifiedPropertyLength = Engine.JsGetStringLength(stringifiedPropertyHandle);
byte[] serializedPropertyBuffer = new byte[stringifiedPropertyLength];
var stringifiedPropertyWritten = Engine.JsCopyString(stringifiedPropertyHandle, serializedPropertyBuffer, (ulong)stringifiedPropertyLength);
firstFrameProperties = Encoding.UTF8.GetString(serializedPropertyBuffer);
//Get information about the 'fibonacci' local -- which should be our function.
var localsPropertyHandle = Engine.JsCreatePropertyId("locals", (ulong)"locals".Length);
var localsHandle = Engine.JsGetProperty(stackProperties, localsPropertyHandle);
var objLocalHandle = Engine.JsGetIndexedProperty(localsHandle, ix);
//I'm not impressed with the naming of these... ;)
var handlePropertyHandle = Engine.JsCreatePropertyId("handle", (ulong)"handle".Length);
var handleHandle = Engine.JsGetProperty(objLocalHandle, handlePropertyHandle);
var handle = Engine.JsNumberToInt(handleHandle);
var objectHandle = Engine.JsDiagGetObjectFromHandle((uint)handle);
var namePropertyHandle = Engine.JsCreatePropertyId("name", (ulong)"name".Length);
var nameHandle = Engine.JsGetProperty(objectHandle, namePropertyHandle);
var nameLength = Engine.JsGetStringLength(nameHandle);
byte[] nameBuffer = new byte[nameLength];
var nameWritten = Engine.JsCopyString(nameHandle, nameBuffer, (ulong)nameLength);
firstStackObjectName = Encoding.UTF8.GetString(nameBuffer);
//Get the child properties
var objectChildrenHandle = Engine.JsDiagGetProperties((uint)handle, 0, 6);
//Stringify the children (muahaha).
var stringifiedChildrenHandle = Engine.JsCallFunction(fnStringifyHandle, new IntPtr[] { globalObjectHandle.DangerousGetHandle(), objectChildrenHandle.DangerousGetHandle() }, 2);
var stringifiedChildrenLength = Engine.JsGetStringLength(stringifiedChildrenHandle);
byte[] serializedChildrenBuffer = new byte[stringifiedChildrenLength];
var stringifiedChildrenWritten = Engine.JsCopyString(stringifiedChildrenHandle, serializedChildrenBuffer, (ulong)stringifiedChildrenLength);
firstFrameChildren = Encoding.UTF8.GetString(serializedChildrenBuffer);
//Set the step
Engine.JsDiagSetStepType(JavaScriptDiagStepType.StepIn);
}
else if (sourceText == "var a = 1")
{
//this is our step.
//do naught.
}
else if (sourceText == "throw new Error('we did it jim!')")
{
//This is the exception we're skipping.
//do naught.
}
//Otherwise...
else
{
var evalScript = Engine.JsCreateString("num", (ulong)"num".Length);
var numHandle = Engine.JsDiagEvaluate(evalScript, 0, JavaScriptParseScriptAttributes.None, false);
var valuePropertyHandle = Engine.JsCreatePropertyId("value", (ulong)"value".Length);
var valueHandle = Engine.JsGetProperty(numHandle, valuePropertyHandle);
numDecrementing.Add(Engine.JsNumberToInt(valueHandle));
}
//Increment our call counter (that we're asserting against) and continue.
calledCount++;
return(true);
};
var callbackHandle = GCHandle.Alloc(callback);
try
{
using (var ss = new ScriptSource(Engine, fibonacci))
{
Engine.JsDiagStartDebugging(runtimeHandle, callback, IntPtr.Zero);
var scripts = Engine.JsDiagGetScripts();
Assert.NotEqual(JavaScriptValueSafeHandle.Invalid, scripts);
var ix = Engine.JsIntToNumber(0);
var objScriptHandle = Engine.JsGetIndexedProperty(scripts, ix);
var handleType = Engine.JsGetValueType(objScriptHandle);
Assert.True(handleType == JsValueType.Object);
//Not sure if the ScriptId varies independently of the ScriptContext cookie
var scriptIdPropertyHandle = Engine.JsCreatePropertyId("scriptId", (ulong)"scriptId".Length);
var scriptIdHandle = Engine.JsGetProperty(objScriptHandle, scriptIdPropertyHandle);
var scriptId = Engine.JsNumberToInt(scriptIdHandle);
//Assert that we can get the source for the script id.
var objSourceHandle = Engine.JsDiagGetSource((uint)scriptId);
var sourcePropertyHandle = Engine.JsCreatePropertyId("source", (ulong)"source".Length);
var sourceHandle = Engine.JsGetProperty(objSourceHandle, sourcePropertyHandle);
handleType = Engine.JsGetValueType(sourceHandle);
Assert.True(handleType == JsValueType.String);
var sourceLength = Engine.JsGetStringLength(sourceHandle);
byte[] buffer = new byte[sourceLength];
var written = Engine.JsCopyString(sourceHandle, buffer, (ulong)sourceLength);
var source = Encoding.UTF8.GetString(buffer);
Assert.Equal(fibonacci, source);
//Set a breakpoint with a knkown position
var breakPointHandle = Engine.JsDiagSetBreakpoint((uint)scriptId, 5, 0);
//Assert that the breakpoint has been set
var breakpointsHandle = Engine.JsDiagGetBreakpoints();
var objBreakpointHandle = Engine.JsGetIndexedProperty(breakpointsHandle, ix);
var breakpointIdPropertyHandle = Engine.JsCreatePropertyId("breakpointId", (ulong)"breakpointId".Length);
var breakpointIdHandle = Engine.JsGetProperty(objBreakpointHandle, breakpointIdPropertyHandle);
var linePropertyHandle = Engine.JsCreatePropertyId("line", (ulong)"line".Length);
var lineHandle = Engine.JsGetProperty(objBreakpointHandle, linePropertyHandle);
var line = Engine.JsNumberToInt(lineHandle);
var breakPointId = Engine.JsNumberToInt(breakpointIdHandle);
Assert.Equal(5, line);
Assert.Equal(1, breakPointId);
//Get/set the break on exception setting.
var breakOnExceptionSetting = Engine.JsDiagGetBreakOnException(runtimeHandle);
Assert.True(breakOnExceptionSetting == JavaScriptDiagBreakOnExceptionAttributes.Uncaught);
Engine.JsDiagSetBreakOnException(runtimeHandle, JavaScriptDiagBreakOnExceptionAttributes.None);
breakOnExceptionSetting = Engine.JsDiagGetBreakOnException(runtimeHandle);
Assert.True(breakOnExceptionSetting == JavaScriptDiagBreakOnExceptionAttributes.None);
//Get the function position
var fibonacciFunctionPositionHandle = Engine.JsDiagGetFunctionPosition(ss.FunctionHandle);
//Stringify the function position.
var stringifiedFibonacciHandle = Engine.JsCallFunction(fnStringifyHandle, new IntPtr[] { globalObjectHandle.DangerousGetHandle(), fibonacciFunctionPositionHandle.DangerousGetHandle() }, 2);
var stringifiedFibonacciLength = Engine.JsGetStringLength(stringifiedFibonacciHandle);
byte[] serializedFibonacciBuffer = new byte[stringifiedFibonacciLength];
var stringifiedFibonacciWritten = Engine.JsCopyString(stringifiedFibonacciHandle, serializedFibonacciBuffer, (ulong)stringifiedFibonacciLength);
fibonacciFunctionPosition = Encoding.UTF8.GetString(serializedFibonacciBuffer);
//Break on the first line
Engine.JsDiagRequestAsyncBreak(runtimeHandle);
var finalResult = Engine.JsCallFunction(ss.FunctionHandle, new IntPtr[] { ss.FunctionHandle.DangerousGetHandle() }, 1);
handleType = Engine.JsGetValueType(finalResult);
//Fib = 51, first break = 1, step = 1. 51+1+1 = 53
Assert.Equal(53, calledCount);
//Remove our previous breakpoint
Engine.JsDiagRemoveBreakpoint((uint)breakPointId);
//Assert the breakpoint has been removed.
breakpointsHandle = Engine.JsDiagGetBreakpoints();
objBreakpointHandle = Engine.JsGetIndexedProperty(breakpointsHandle, ix);
handleType = Engine.JsGetValueType(objBreakpointHandle);
Assert.True(handleType == JsValueType.Undefined);
Engine.JsDiagStopDebugging(runtimeHandle);
}
Assert.True(firstLineHit);
Assert.False(string.IsNullOrWhiteSpace(fibonacciFunctionPosition));
Assert.False(string.IsNullOrWhiteSpace(firstFrameProperties));
Assert.False(string.IsNullOrWhiteSpace(firstFrameChildren));
Assert.Equal("fibonacci", firstStackObjectName);
Assert.True(numDecrementing.Count == 51);
}
finally
{
callbackHandle.Free();
}
}
}
}