Use the FutureBackend approach by default, if the backend implements it

Author: HenrikBengtsson

.github/workflows/R-CMD-check.yaml

@@ -28,7 +28,7 @@ jobs:
           - {os: ubuntu-latest,  r: 'oldrel-1' }
           - {os: ubuntu-latest,  r: 'oldrel-2' }
           - {os: ubuntu-latest,  r: '4.0'      }
-          - {os: ubuntu-latest,  r: 'release'  , backend_version: 2, label: 'backend_version=2' }
+          - {os: ubuntu-latest,  r: 'release'  , backend_version: 1, label: 'backend_version=1' }
           - {os: ubuntu-latest,  r: 'release'  , language: ko,    label: ko    }
           - {os: ubuntu-latest,  r: 'release'  , language: zh_CN, label: zh_CN }
           - {os: ubuntu-latest,  r: 'release'  , language: zh_TW, label: zh_TW }

DESCRIPTION

@@ -1,5 +1,5 @@
 Package: future
-Version: 1.34.0-9202
+Version: 1.34.0-9203
 Title: Unified Parallel and Distributed Processing in R for Everyone
 Imports:
     digest,

R/backend_api-Future-class.R

@@ -428,7 +428,7 @@ run.Future <- function(future, ...) {
   if (debug) mdebug("- Future backend: ", commaq(class(makeFuture)))
 
   ## Use new FutureBackend approach?
-  if (getOption("future.backend.version", 1L) == 2L) {
+  if (getOption("future.backend.version", 2L) == 2L) {
     ## Implements a FutureBackend?
     backend <- attr(makeFuture, "backend")
     if (is.function(backend)) {