Function to use synchronously a function returning its value by a lambda

resynchronize.kt

package com.github.gist.mbiamont

import kotlinx.coroutines.runBlocking
import kotlin.coroutines.resume
import kotlin.coroutines.resumeWithException
import kotlin.coroutines.suspendCoroutine


inline fun <T> resynchronize(crossinline block: (onSuccess: (result: T) -> Unit, onError: (e: Throwable) -> Unit) -> Unit): T {
    return runBlocking {
        suspendCoroutine<T> { continuation ->
            block.invoke({ result ->
                continuation.resume(result)
            }, { e ->
                continuation.resumeWithException(e)
            })
        }
    }
}

inline fun <T> resynchronize(crossinline block: (onSuccess: (result: T) -> Unit) -> Unit): T {
    return runBlocking {
        suspendCoroutine<T> { continuation ->
            block.invoke { result ->
                continuation.resume(result)
            }
        }
    }
}


inline fun <T, V> resynchronize(p1: V, crossinline block: (p1: V, onSuccess: (result: T) -> Unit) -> Unit): T {
    return runBlocking {
        suspendCoroutine<T> { continuation ->
            block.invoke(p1) { result ->
                continuation.resume(result)
            }
        }
    }
}


inline fun <T, V> resynchronize(
    p1: V,
    crossinline block: (p1: V, onSuccess: (result: T) -> Unit, onError: (e: Throwable) -> Unit) -> Unit
): T {
    return runBlocking {
        suspendCoroutine<T> { continuation ->
            block.invoke(p1, { result ->
                continuation.resume(result)
            }, { e ->
                continuation.resumeWithException(e)
            })
        }
    }
}

sample.kt

package com.github.gist.mbiamont


class UserRepository(
    private val localUserService: ILocalUserService
) : UserDataSource {
  
    fun getAccessToken() : String = resynchronize(::getAccessTokenAsync)

    private fun getAccessTokenAsync(onSuccess: (accessToken: String) -> Unit, onError: (e: Throwable) -> Unit) =
        localUserService.getUserAccessToken(onSuccess, onError)
}