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JavaScript javascript image promise stuck in constructor class

vissaeus

New Coder
the code gets stuck in a promise (prom1) when image onload. I using await promise inside drawCanvas() because i need to work with this.image after it has loaded.

HTML:
<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Untitled</title>
    <style>body{margin:0;padding:0;background:rgb(30,60,90);}
    canvas{border:1px solid white;background-color:white}
    </style>
    <canvas id="canvas2" width="120" height= "144" style="border:1px solid black;margin:0 auto;display:block;background:lightgray"></canvas>
    <canvas id="canvas3" width="120" height= "144" style="border:1px solid black;margin:0 auto;display:block;background:lightgray"></canvas>
</head>
<body>
    <script src="main.js"></script>
</body>
</html>

JavaScript:
var tempClass = function(_cfg) {

this.image = new Image()
    this.image.src = _cfg.src
}

tempClass.prototype.drawCanvas = async function(_arg) {
    let prom1 = await new Promise(resolve => {
        this.image.onload = _=> {resolve()}
    })
    console.log('done: ' + _arg)
}

var handler = new tempClass({src: 'vulture.png?var=' + Math.random()})

handler.drawCanvas(1)
handler.drawCanvas(2)

vulture.png: vulture.png
 
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