Merge pull request #553 from JuliaParallel/jps/dtask-sync-fix

@Spawn: Properly rethrow in @sync

Author: jpsamaroo

Diff for: src/thunk.jl

@@ -402,7 +402,7 @@ function _par(ex::Expr; lazy=true, recur=true, opts=())
                 let
                     $result = $spawn($f, $Options(;$(opts...)), $(args...); $(kwargs...))
                     if $(Expr(:islocal, sync_var))
-                        put!($sync_var, schedule(Task(()->wait($result))))
+                        put!($sync_var, schedule(Task(()->fetch($result; raw=true))))
                     end
                     $result
                 end

Diff for: test/thunk.jl

@@ -348,5 +348,9 @@ end
             result = Dagger.@spawn sleep(1)
         end
         @test isready(result)
+
+        @test_throws Exception @sync begin
+            Dagger.@spawn error()
+        end
     end
 end