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Promise inside of forEach in Typescript

I have the following code:

original_test(){
    var arr=[1,2,3]
    arr.forEach((a: any) => {
        console.log("Before")
        this.test().then(()=>{
            console.log("After")
        });
    });
}
test(){
    return new Promise((resolve) => {
        resolve(true)
    });
 }

My problem is that I want my code to wait for the next iteration of forEach (until the promise completes). That means I want as console output:

"Before"

"After"

"Before"

"After"

"Before"

"After"

And what I get is:

"Before"

"Before"

"Before"

"After"

"After"

"After"

Many thanks!

I would do it like this:

async original_test() {
    var arr=[1, 2, 3];
    for(const item of arr) {
        console.log("Before")
        await this.test()
        console.log("After")
    }
};

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