1 files changed, 135 insertions, 0 deletions
diff --git a/tests/AtomicState_test.cpp b/tests/AtomicState_test.cpp
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+++ b/tests/AtomicState_test.cpp
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+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <AtomicState.h>
+
+#include <chrono>
+#include <thread>
+
+#include <gtest/gtest.h>
+
+using namespace std::chrono_literals;
+
+namespace android {
+
+enum AtomicStateTestEnum {
+  A,
+  B,
+  C,
+  D,
+  E,
+};
+
+class AtomicStateTest : public testing::Test {
+ protected:
+  AtomicStateTest() : state_(A) {}
+  virtual void SetUp() {}
+  virtual void TearDown() {}
+
+  AtomicState<AtomicStateTestEnum> state_;
+};
+
+TEST_F(AtomicStateTest, transition) {
+  ASSERT_EQ(A, state_.state_);
+
+  // Starts as A, transition from B fails
+  ASSERT_FALSE(state_.transition(B, C));
+  ASSERT_EQ(A, state_.state_);
+
+  // transition from A to B
+  ASSERT_TRUE(state_.transition(A, B));
+  ASSERT_EQ(B, state_.state_);
+
+  // State is B, transition from A fails
+  ASSERT_FALSE(state_.transition(A, B));
+  ASSERT_EQ(B, state_.state_);
+
+  // State is B, transition_or from A calls the lambda
+  bool lambda = false;
+  bool already_locked = false;
+  state_.transition_or(A, B, [&] {
+    // The lock should be held in the lambda
+    if (state_.m_.try_lock()) {
+      state_.m_.unlock();
+    } else {
+      already_locked = true;
+    }
+    lambda = true;
+    return B;
+  });
+  ASSERT_TRUE(lambda);
+  ASSERT_TRUE(already_locked);
+  ASSERT_EQ(B, state_.state_);
+
+  // State is C, transition_or from B to C does not call the lambda
+  lambda = false;
+  state_.transition_or(B, C, [&] {
+    lambda = true;
+    return C;
+  });
+  ASSERT_FALSE(lambda);
+  ASSERT_EQ(C, state_.state_);
+}
+
+TEST_F(AtomicStateTest, wait) {
+  ASSERT_EQ(A, state_.state_);
+
+  // Starts as A, wait_for_either_of B, C returns false
+  ASSERT_FALSE(state_.wait_for_either_of(B, C, 10ms));
+
+  // Starts as A, wait_for_either_of A, B returns true
+  ASSERT_TRUE(state_.wait_for_either_of(A, B, 1s));
+
+  {
+    std::thread t([&] {
+      usleep(10000);
+      state_.set(B);
+    });
+
+    // Wait ing for B or C returns true after state is set to B
+    ASSERT_TRUE(state_.wait_for_either_of(B, C, 1s));
+
+    t.join();
+  }
+
+  ASSERT_EQ(B, state_.state_);
+  {
+    std::thread t([&] {
+      usleep(10000);
+      state_.transition(B, C);
+    });
+
+    // Waiting for A or C returns true after state is transitioned to C
+    ASSERT_TRUE(state_.wait_for_either_of(A, C, 1s));
+
+    t.join();
+  }
+
+  ASSERT_EQ(C, state_.state_);
+  {
+    std::thread t([&] {
+      usleep(10000);
+      state_.transition(C, D);
+    });
+
+    // Waiting for A or B returns false after state is transitioned to D
+    ASSERT_FALSE(state_.wait_for_either_of(A, B, 100ms));
+
+    t.join();
+  }
+}
+
+}  // namespace android