Add unit tests for memory pressure events.

PiperOrigin-RevId: 415110987

src/test/java/com/google/devtools/build/lib/BUILD

@@ -40,6 +40,7 @@ filegroup(
         "//src/test/java/com/google/devtools/build/lib/packages/metrics:srcs",
         "//src/test/java/com/google/devtools/build/lib/packages/semantics:srcs",
         "//src/test/java/com/google/devtools/build/lib/platform:srcs",
+        "//src/test/java/com/google/devtools/build/lib/platform/darwin:srcs",
         "//src/test/java/com/google/devtools/build/lib/profiler:srcs",
         "//src/test/java/com/google/devtools/build/lib/profiler/callcounts:srcs",
         "//src/test/java/com/google/devtools/build/lib/profiler/memory:srcs",

src/test/java/com/google/devtools/build/lib/platform/BUILD

@@ -39,3 +39,27 @@ java_test(
         "//third_party:truth",
     ],
 )
+
+java_test(
+    name = "SystemMemoryPressureEventTest",
+    timeout = "short",
+    srcs = ["SystemMemoryPressureEventTest.java"],
+    data = select({
+        "//src/conditions:darwin": [
+            "//src/test/java/com/google/devtools/build/lib/platform/darwin:notifier",
+        ],
+        "//conditions:default": [
+        ],
+    }),
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib:runtime",
+        "//src/main/java/com/google/devtools/build/lib/platform:system_memory_pressure_module",
+        "//src/main/java/com/google/devtools/build/lib/platform:system_memory_pressure_monitor",
+        "//src/main/java/com/google/devtools/build/lib/util:os",
+        "//src/test/java/com/google/devtools/build/lib/buildtool/util",
+        "//third_party:guava",
+        "//third_party:junit4",
+        "//third_party:truth",
+        "@bazel_tools//tools/java/runfiles",
+    ],
+)

src/test/java/com/google/devtools/build/lib/platform/SystemMemoryPressureEventTest.java

@@ -0,0 +1,92 @@
+// Copyright 2021 The Bazel Authors. All rights reserved.
+//
+// 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.
+
+package com.google.devtools.build.lib.platform;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import com.google.common.eventbus.Subscribe;
+import com.google.devtools.build.lib.buildtool.util.BuildIntegrationTestCase;
+import com.google.devtools.build.lib.runtime.BlazeModule;
+import com.google.devtools.build.lib.runtime.BlazeRuntime;
+import com.google.devtools.build.lib.runtime.CommandEnvironment;
+import com.google.devtools.build.lib.util.OS;
+import com.google.devtools.build.runfiles.Runfiles;
+import org.junit.Assume;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Tests {@link SystemMemoryPressureEvent} by sending fake notifications. */
+@RunWith(JUnit4.class)
+public final class SystemMemoryPressureEventTest extends BuildIntegrationTestCase {
+  static class SystemMemoryPressureEventListener extends BlazeModule {
+    public int memoryPressureWarningEventCount = 0;
+    public int memoryPressureCriticalEventCount = 0;
+
+    @Override
+    public void beforeCommand(CommandEnvironment env) {
+      env.getEventBus().register(this);
+    }
+
+    @Subscribe
+    public void memoryPressureEvent(SystemMemoryPressureEvent event) {
+      switch (event.level()) {
+        case WARNING:
+          ++memoryPressureWarningEventCount;
+          assertThat(event.logString()).isEqualTo("SystemMemoryPressureEvent: Warning");
+          break;
+
+        case CRITICAL:
+          ++memoryPressureCriticalEventCount;
+          assertThat(event.logString()).isEqualTo("SystemMemoryPressureEvent: Critical");
+          break;
+      }
+    }
+  }
+
+  private final SystemMemoryPressureEventListener eventListener =
+      new SystemMemoryPressureEventListener();
+
+  @Override
+  protected BlazeRuntime.Builder getRuntimeBuilder() throws Exception {
+    return super.getRuntimeBuilder()
+        .addBlazeModule(eventListener)
+        .addBlazeModule(new SystemMemoryPressureModule());
+  }
+
+  @Test
+  public void testMemoryPressure() throws Exception {
+    Assume.assumeTrue(OS.getCurrent() == OS.DARWIN);
+    Runfiles runfiles = Runfiles.create();
+    String notifierFilePath =
+        runfiles.rlocation(
+            "io_bazel/src/test/java/com/google/devtools/build/lib/platform/darwin/notifier");
+    write(
+        "system_suspension_event/BUILD",
+        "genrule(",
+        "  name = 'fire_memory_pressure_notifications',",
+        "  outs = ['fire_memory_pressure_notifications.out'],",
+        "  cmd = '"
+            + notifierFilePath
+            + " com.google.bazel.test.memorypressurelevel.warning 0 > $@; ' + ",
+        "        '"
+            + notifierFilePath
+            + " com.google.bazel.test.memorypressurelevel.critical 0 >> $@',",
+        ")");
+    buildTarget("//system_suspension_event:fire_memory_pressure_notifications");
+    assertThat(eventListener.memoryPressureWarningEventCount).isGreaterThan(0);
+    assertThat(eventListener.memoryPressureCriticalEventCount).isGreaterThan(0);
+  }
+}

src/test/java/com/google/devtools/build/lib/platform/darwin/BUILD

@@ -7,6 +7,13 @@ package(
 
 licenses(["notice"])
 
+filegroup(
+    name = "srcs",
+    testonly = 0,
+    srcs = glob(["**"]),
+    visibility = ["//src:__subpackages__"],
+)
+
 # Utility for sending notifications. It expects one arg which is the
 # notification to send using the notify_post (3) api.
 cc_binary(