3 files changed, 93 insertions, 8 deletions
diff --git a/core/java/com/android/internal/util/StateMachine.java b/core/java/com/android/internal/util/StateMachine.java
index d67cef3f0dda..8d9630fe5654 100644
--- a/core/java/com/android/internal/util/StateMachine.java
+++ b/core/java/com/android/internal/util/StateMachine.java
@@ -2070,8 +2070,6 @@ public class StateMachine {
      * @param args
      */
     public void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
-        // Cannot just invoke pw.println(this.toString()) because if the
-        // resulting string is to long it won't be displayed.
         pw.println(getName() + ":");
         pw.println(" total records=" + getLogRecCount());
         for (int i = 0; i < getLogRecSize(); i++) {
@@ -2083,12 +2081,15 @@ public class StateMachine {
 
     @Override
     public String toString() {
-        StringWriter sr = new StringWriter();
-        PrintWriter pr = new PrintWriter(sr);
-        dump(null, pr, null);
-        pr.flush();
-        pr.close();
-        return sr.toString();
+        String name = "(null)";
+        String state = "(null)";
+        try {
+            name = mName.toString();
+            state = mSmHandler.getCurrentState().getName().toString();
+        } catch (NullPointerException npe) {
+            // Will use default(s) initialized above.
+        }
+        return "name=" + name + " state=" + state;
     }
 
     /**
diff --git a/core/tests/utiltests/runtests.sh b/core/tests/utiltests/runtests.sh
new file mode 100755
index 000000000000..853119f62334
--- /dev/null
+++ b/core/tests/utiltests/runtests.sh
@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+
+if [ -z $ANDROID_BUILD_TOP ]; then
+  echo "You need to source and lunch before you can use this script"
+  exit 1
+fi
+
+echo "Running tests"
+
+set -e # fail early
+
+echo "+ mmma -j32 $ANDROID_BUILD_TOP/frameworks/base/core/tests/utiltests"
+# NOTE Don't actually run the command above since this shell doesn't inherit functions from the
+#      caller.
+make -j32 -C $ANDROID_BUILD_TOP -f build/core/main.mk MODULES-IN-frameworks-base-core-tests-utiltests
+
+set -x # print commands
+
+adb root
+adb wait-for-device
+
+adb install -r -g "$OUT/data/app/FrameworksUtilTests/FrameworksUtilTests.apk"
+
+adb shell am instrument -w "$@" 'com.android.frameworks.utiltests/android.support.test.runner.AndroidJUnitRunner'
diff --git a/core/tests/utiltests/src/com/android/internal/util/StateMachineTest.java b/core/tests/utiltests/src/com/android/internal/util/StateMachineTest.java
index d29b5723065b..eb2a5165dc4f 100644
--- a/core/tests/utiltests/src/com/android/internal/util/StateMachineTest.java
+++ b/core/tests/utiltests/src/com/android/internal/util/StateMachineTest.java
@@ -80,6 +80,66 @@ public class StateMachineTest extends TestCase {
     }
 
     /**
+     * Tests {@link StateMachine#toString()}.
+     */
+    class StateMachineToStringTest extends StateMachine {
+        StateMachineToStringTest(String name) {
+            super(name);
+        }
+    }
+
+    class ExampleState extends State {
+        String mName;
+
+        ExampleState(String name) {
+            mName = name;
+        }
+
+        @Override
+        public String getName() {
+            return mName;
+        }
+    }
+
+    @SmallTest
+    public void testToStringSucceedsEvenIfMachineHasNoStates() throws Exception {
+        StateMachine stateMachine = new StateMachineToStringTest("TestStateMachine");
+        assertTrue(stateMachine.toString().contains("TestStateMachine"));
+    }
+
+    @SmallTest
+    public void testToStringSucceedsEvenIfStateHasNoName() throws Exception {
+        StateMachine stateMachine = new StateMachineToStringTest("TestStateMachine");
+        State exampleState = new ExampleState(null);
+        stateMachine.addState(exampleState);
+        stateMachine.setInitialState(exampleState);
+        stateMachine.start();
+        assertTrue(stateMachine.toString().contains("TestStateMachine"));
+        assertTrue(stateMachine.toString().contains("(null)"));
+    }
+
+    @SmallTest
+    public void testToStringIncludesMachineAndStateNames() throws Exception {
+        StateMachine stateMachine = new StateMachineToStringTest("TestStateMachine");
+        State exampleState = new ExampleState("exampleState");
+        stateMachine.addState(exampleState);
+        stateMachine.setInitialState(exampleState);
+        stateMachine.start();
+        assertTrue(stateMachine.toString().contains("TestStateMachine"));
+        assertTrue(stateMachine.toString().contains("exampleState"));
+    }
+
+    @SmallTest
+    public void testToStringDoesNotContainMultipleLines() throws Exception {
+        StateMachine stateMachine = new StateMachineToStringTest("TestStateMachine");
+        State exampleState = new ExampleState("exampleState");
+        stateMachine.addState(exampleState);
+        stateMachine.setInitialState(exampleState);
+        stateMachine.start();
+        assertFalse(stateMachine.toString().contains("\n"));
+    }
+
+    /**
      * Tests {@link StateMachine#quit()}.
      */
     class StateMachineQuitTest extends StateMachine {