Skip to content

F
folly
Commit e0d04ed7 authored by Lee Howes's avatar Lee Howes Committed by Facebook Github Bot
Browse files
Options

Add getSemiFuture and storage of executor to FutureSplitter so that returned... 

Add getSemiFuture and storage of executor to FutureSplitter so that returned future completes on the expected executor.

Summary:
Remove calls to Promise::getFuture in FutureSplitter test.

Add getSemiFuture to FutureSplitter for consistency with Promise.

Keep getFuture method but ensure that it completes on the same executor as the input future (or Inline if the executor on the input future was null, due to legacy code).

Reviewed By: yfeldblum

Differential Revision: D7105806

fbshipit-source-id: 63a919ba9dcf0f189782a3e2a362fad4d86ac91f
parent f0d42801
Hide whitespace changes
Inline Side-by-side
Showing with 81 additions and 18 deletions
folly/futures/Future.h
View file @ e0d04ed7
......@@ -48,6 +48,9 @@ class Future;
template <class T>
class SemiFuture;
template <class T>
class FutureSplitter;
namespace futures {
namespace detail {
template <class T>
......@@ -781,6 +784,8 @@ class Future : private futures::detail::FutureBase<T> {
friend class Future;
template <class>
friend class SemiFuture;
template <class>
friend class FutureSplitter;
using Base::setExecutor;
using Base::throwIfInvalid;
......
folly/futures/FutureSplitter.h
View file @ e0d04ed7
......@@ -45,8 +45,9 @@ class FutureSplitter {
* Provide a way to split a Future<T>.
*/
explicit FutureSplitter(Future<T>&& future)
: promise_(std::make_shared<SharedPromise<T>>()) {
future.then([promise = promise_](Try<T> && theTry) {
: promise_(std::make_shared<SharedPromise<T>>()),
e_(getExecutorFrom(future)) {
future.then([promise = promise_](Try<T>&& theTry) {
promise->setTry(std::move(theTry));
});
}
......@@ -58,11 +59,29 @@ class FutureSplitter {
if (promise_ == nullptr) {
throwNoFutureInSplitter();
}
return promise_->getFuture();
return promise_->getSemiFuture().via(e_);
}
/**
* This can be called an unlimited number of times per FutureSplitter.
*/
SemiFuture<T> getSemiFuture() {
if (promise_ == nullptr) {
throwNoFutureInSplitter();
}
return promise_->getSemiFuture();
}
private:
std::shared_ptr<SharedPromise<T>> promise_;
Executor* e_ = nullptr;
static Executor* getExecutorFrom(Future<T>& f) {
// If the passed future had a null executor, use an inline executor
// to ensure that .via is safe
auto* e = f.getExecutor();
return e ? e : &folly::InlineExecutor::instance();
}
};
/**
......
folly/futures/test/FutureSplitterTest.cpp
View file @ e0d04ed7
......@@ -21,7 +21,40 @@ using namespace folly;
TEST(FutureSplitter, splitFutureSuccess) {
Promise<int> p;
FutureSplitter<int> sp(p.getFuture());
folly::FutureSplitter<int> sp(
p.getSemiFuture().via(&folly::InlineExecutor::instance()));
auto f1 = sp.getFuture();
EXPECT_FALSE(f1.isReady());
p.setValue(1);
EXPECT_TRUE(f1.isReady());
EXPECT_TRUE(f1.hasValue());
auto f2 = sp.getFuture();
EXPECT_TRUE(f2.isReady());
EXPECT_TRUE(f2.hasValue());
}
TEST(FutureSplitter, splitFutureSuccessSemiFuture) {
Promise<int> p;
folly::FutureSplitter<int> sp(
p.getSemiFuture().via(&folly::InlineExecutor::instance()));
auto f1 = sp.getSemiFuture();
EXPECT_FALSE(f1.isReady());
p.setValue(1);
EXPECT_TRUE(f1.isReady());
EXPECT_TRUE(f1.hasValue());
auto f2 = sp.getSemiFuture();
EXPECT_TRUE(f2.isReady());
EXPECT_TRUE(f2.hasValue());
}
TEST(FutureSplitter, splitFutureSuccessNullExecutor) {
Promise<int> p;
auto sf = p.getSemiFuture();
// Double via because a null executor to SemiFuture.via is invalid but we
// are testing a situation where we have a FutureSplitter from a future with
// a null executor to account for legacy code.
auto f = std::move(sf).via(&folly::InlineExecutor::instance()).via(nullptr);
folly::FutureSplitter<int> sp(std::move(f));
auto f1 = sp.getFuture();
EXPECT_FALSE(f1.isReady());
p.setValue(1);
......@@ -34,8 +67,9 @@ TEST(FutureSplitter, splitFutureSuccess) {
TEST(FutureSplitter, splitFutureCopyable) {
Promise<int> p;
FutureSplitter<int> sp1(p.getFuture());
FutureSplitter<int> sp2(sp1);
folly::FutureSplitter<int> sp1(
p.getSemiFuture().via(&folly::InlineExecutor::instance()));
folly::FutureSplitter<int> sp2(sp1);
auto f1 = sp1.getFuture();
EXPECT_FALSE(f1.isReady());
p.setValue(1);
......@@ -44,7 +78,7 @@ TEST(FutureSplitter, splitFutureCopyable) {
auto f2 = sp2.getFuture();
EXPECT_TRUE(f2.isReady());
EXPECT_TRUE(f2.hasValue());
FutureSplitter<int> sp3(sp1);
folly::FutureSplitter<int> sp3(sp1);
auto f3 = sp3.getFuture();
EXPECT_TRUE(f3.isReady());
EXPECT_TRUE(f3.hasValue());
......@@ -52,9 +86,10 @@ TEST(FutureSplitter, splitFutureCopyable) {
TEST(FutureSplitter, splitFutureMovable) {
Promise<int> p;
FutureSplitter<int> sp1(p.getFuture());
folly::FutureSplitter<int> sp1(
p.getSemiFuture().via(&folly::InlineExecutor::instance()));
auto f1 = sp1.getFuture();
FutureSplitter<int> sp2(std::move(sp1));
folly::FutureSplitter<int> sp2(std::move(sp1));
EXPECT_FALSE(f1.isReady());
p.setValue(1);
EXPECT_TRUE(f1.isReady());
......@@ -62,7 +97,7 @@ TEST(FutureSplitter, splitFutureMovable) {
auto f2 = sp2.getFuture();
EXPECT_TRUE(f2.isReady());
EXPECT_TRUE(f2.hasValue());
FutureSplitter<int> sp3(std::move(sp2));
folly::FutureSplitter<int> sp3(std::move(sp2));
auto f3 = sp3.getFuture();
EXPECT_TRUE(f3.isReady());
EXPECT_TRUE(f3.hasValue());
......@@ -70,8 +105,9 @@ TEST(FutureSplitter, splitFutureMovable) {
TEST(FutureSplitter, splitFutureCopyAssignable) {
Promise<int> p;
FutureSplitter<int> sp1(p.getFuture());
FutureSplitter<int> sp2{};
folly::FutureSplitter<int> sp1(
p.getSemiFuture().via(&folly::InlineExecutor::instance()));
folly::FutureSplitter<int> sp2{};
sp2 = sp1;
auto f1 = sp1.getFuture();
EXPECT_FALSE(f1.isReady());
......@@ -81,7 +117,7 @@ TEST(FutureSplitter, splitFutureCopyAssignable) {
auto f2 = sp2.getFuture();
EXPECT_TRUE(f2.isReady());
EXPECT_TRUE(f2.hasValue());
FutureSplitter<int> sp3(sp1);
folly::FutureSplitter<int> sp3(sp1);
auto f3 = sp3.getFuture();
EXPECT_TRUE(f3.isReady());
EXPECT_TRUE(f3.hasValue());
......@@ -89,9 +125,10 @@ TEST(FutureSplitter, splitFutureCopyAssignable) {
TEST(FutureSplitter, splitFutureMoveAssignable) {
Promise<int> p;
FutureSplitter<int> sp1(p.getFuture());
folly::FutureSplitter<int> sp1(
p.getSemiFuture().via(&folly::InlineExecutor::instance()));
auto f1 = sp1.getFuture();
FutureSplitter<int> sp2{};
folly::FutureSplitter<int> sp2{};
sp2 = std::move(sp1);
EXPECT_FALSE(f1.isReady());
p.setValue(1);
......@@ -100,7 +137,7 @@ TEST(FutureSplitter, splitFutureMoveAssignable) {
auto f2 = sp2.getFuture();
EXPECT_TRUE(f2.isReady());
EXPECT_TRUE(f2.hasValue());
FutureSplitter<int> sp3(std::move(sp2));
folly::FutureSplitter<int> sp3(std::move(sp2));
auto f3 = sp3.getFuture();
EXPECT_TRUE(f3.isReady());
EXPECT_TRUE(f3.hasValue());
......@@ -108,7 +145,8 @@ TEST(FutureSplitter, splitFutureMoveAssignable) {
TEST(FutureSplitter, splitFutureScope) {
Promise<int> p;
auto pSP = std::make_unique<FutureSplitter<int>>(p.getFuture());
auto pSP = std::make_unique<folly::FutureSplitter<int>>(
p.getSemiFuture().via(&folly::InlineExecutor::instance()));
auto f1 = pSP->getFuture();
EXPECT_FALSE(f1.isReady());
pSP.reset();
......@@ -121,7 +159,8 @@ TEST(FutureSplitter, splitFutureScope) {
TEST(FutureSplitter, splitFutureFailure) {
Promise<int> p;
FutureSplitter<int> sp(p.getFuture());
folly::FutureSplitter<int> sp(
p.getSemiFuture().via(&folly::InlineExecutor::instance()));
auto f1 = sp.getFuture();
EXPECT_FALSE(f1.isReady());
try {
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment