MOJavaScriptObject function execution

MOJavaScriptObject.m

@import JavaScriptCore;

///	Retaining MOJavaScriptObject retains your JSContext/JSObject as well

@interface MOJavaScriptObject : NSObject

	@property (readonly) JSObjectRef JSObject;

	@property (readonly) JSContextRef JSContext;

@end
  
@implementation MOJavaScriptObject ()
 
	- (JSValue*) callWithArguments:(NSArray*)argumentsArray {
		JSContext *context = [JSContext contextWithJSGlobalContextRef:(JSGlobalContextRef)self.JSContext];
		JSValue *function = [JSValue valueWithJSValueRef:self.JSObject inContext:context];
		
		return [function callWithArguments:argumentsArray];
	}

@end

Thanks Matt, in additional to the original questions, I was trying to execute the code in background. I dispatched the operation in a global queue caused crash, even main thread caused crash. Would you happen to have some pointers for me on that?

// This works
- (void)runSomething:(MOJavaScriptObject *)closure {
    NSArray *args = @[@1, @3];
    JSContext *ctx = [JSContext contextWithJSGlobalContextRef:(JSGlobalContextRef)closure.JSContext];
    JSObjectRef fn = [closure JSObject];
    JSValue *value = [JSValue valueWithJSValueRef:fn inContext:ctx];
    JSValue *result = [value callWithArguments:args];   // result = 4

    NSLog(@"result %@", [result toString]);    // prints "result 4";
}


// This version is causing crash
- (void)runSomething:(MOJavaScriptObject *)closure  {
    dispatch_async(dispatch_get_main_queue(), ^{
        NSArray *args = @[@1, @3];
        JSContext *ctx = [JSContext contextWithJSGlobalContextRef:(JSGlobalContextRef)closure.JSContext];
        JSObjectRef fn = [closure JSObject];
        JSValue *value = [JSValue valueWithJSValueRef:fn inContext:ctx];
        JSValue *result = [value callWithArguments:args];       // cause crash here

        NSLog(@"result %@", [result toString]);
    });
}

@jamztang can you paste your closure code witch is how you trigger the runSomething method.

@jamztang I'm trying to do the exact same thing. I was not able to get this working. Do you mind sharing a full example?

What functions you expose in cocoascript?
And how do you call them from the framework code?

For anyone else who finds this gist and has the same questions as @websiddu and @nikogu:

The problem in James's case was that his JSContext was being released by Sketch before the function could execute. The solution was to use coscript.setShouldKeepAround(true) to prevent Sketch from releasing the context early.

@jamztang can you paste your closure code witch is how you trigger the runSomething method.

fn1(a, b) { return a + b; }