Move CancellationFlag to absl::AnyInvocable

PiperOrigin-RevId: 490078293

Package.resolved

@@ -6,7 +6,7 @@
         "repositoryURL": "https://github.com/firebase/abseil-cpp-SwiftPM.git",
         "state": {
           "branch": "main",
-          "revision": "d302de612e3d57c6f4afaf087da18fba8eac72a7",
+          "revision": "da43cbe34db0763a8eaf986ebda8510e7820d7f7",
           "version": null
         }
       },

internal/platform/BUILD

@@ -136,8 +136,8 @@ cc_library(
     ],
     deps = [
         ":base",
-        ":util",
         "@com_google_absl//absl/container:flat_hash_set",
+        "@com_google_absl//absl/functional:any_invocable",
         "@com_google_absl//absl/synchronization",
     ],
 )

internal/platform/cancellation_flag.cc

@@ -48,7 +48,7 @@ void CancellationFlag::Cancel() {
     listeners = listeners_;
   }
 
-  for (const auto *listener : listeners) {
+  for (auto *listener : listeners) {
     (*listener)();
   }
 }

internal/platform/cancellation_flag.h

@@ -18,6 +18,7 @@
 #include <memory>
 
 #include "absl/container/flat_hash_set.h"
+#include "absl/functional/any_invocable.h"
 #include "absl/synchronization/mutex.h"
 
 namespace location {
@@ -28,7 +29,7 @@ namespace nearby {
 class CancellationFlag {
  public:
   // The listener for cancellation.
-  using CancelListener = std::function<void()>;
+  using CancelListener = absl::AnyInvocable<void()>;
 
   CancellationFlag();
   explicit CancellationFlag(bool cancelled);

internal/platform/cancellation_flag_listener.h

@@ -25,7 +25,7 @@ namespace nearby {
 class CancellationFlagListener {
  public:
   CancellationFlagListener(CancellationFlag* flag,
-                           std::function<void()> listener)
+                           CancellationFlag::CancelListener listener)
       : flag_(flag), listener_(std::move(listener)) {
     flag_->RegisterOnCancelListener(&listener_);
   }
@@ -34,7 +34,7 @@ class CancellationFlagListener {
 
  private:
   CancellationFlag* flag_;
-  std::function<void()> listener_;
+  CancellationFlag::CancelListener listener_;
 };
 
 }  // namespace nearby

internal/platform/cancellation_flag_test.cc

@@ -14,7 +14,9 @@
 
 #include "internal/platform/cancellation_flag.h"
 
+#include <functional>
 #include <memory>
+#include <utility>
 
 #include "gmock/gmock.h"
 #include "protobuf-matchers/protocol-buffer-matchers.h"
@@ -96,7 +98,8 @@ TEST_P(CancellationFlagTest, CanCancel) {
   EXPECT_CALL(mock_cancel_callback, Call)
       .Times(feature_flags_.enable_cancellation_flag ? 1 : 0);
   CancellationFlag flag;
-  CancellationFlagListener cancellation_flag_listener(&flag, cancel_callback);
+  CancellationFlagListener cancellation_flag_listener(
+      &flag, std::move(cancel_callback));
   flag.Cancel();
 
   // If FeatureFlag is disabled, return as no-op immediately and
@@ -117,7 +120,8 @@ TEST_P(CancellationFlagTest, ShouldOnlyCancelOnce) {
       .Times(feature_flags_.enable_cancellation_flag ? 1 : 0);
 
   CancellationFlag flag;
-  CancellationFlagListener cancellation_flag_listener(&flag, cancel_callback);
+  CancellationFlagListener cancellation_flag_listener(
+      &flag, std::move(cancel_callback));
   flag.Cancel();
   flag.Cancel();
   flag.Cancel();
@@ -139,8 +143,8 @@ TEST_P(CancellationFlagTest, CannotCancelAfterUnregister) {
   EXPECT_CALL(mock_cancel_callback, Call).Times(0);
 
   CancellationFlag flag;
-  auto cancellation_flag_listener =
-      std::make_unique<CancellationFlagListener>(&flag, cancel_callback);
+  auto cancellation_flag_listener = std::make_unique<CancellationFlagListener>(
+      &flag, std::move(cancel_callback));
   // Release immediately.
   cancellation_flag_listener.reset();
   flag.Cancel();
@@ -162,11 +166,12 @@ TEST(CancellationFlagTest,
   StrictMock<MockFunction<void()>> mock_cancel_callback;
   CancellationFlag::CancelListener cancel_callback =
       mock_cancel_callback.AsStdFunction();
+  CancellationFlag::CancelListener cancel_callback_copy =
+      mock_cancel_callback.AsStdFunction();
 
   CancellationFlag::CancelListener* callback_pointer_1 = &cancel_callback;
-  auto callback_pointer_2 =
-      std::make_unique<CancellationFlag::CancelListener>();
-  *callback_pointer_2 = cancel_callback;
+  auto callback_pointer_2 = std::make_unique<CancellationFlag::CancelListener>(
+      std::move(cancel_callback_copy));
 
   EXPECT_NE(callback_pointer_1, callback_pointer_2.get());
   EXPECT_CALL(mock_cancel_callback, Call).Times(2);