Merge \"Add ApplicationErrorReport tests\" into nyc-mr1-dev

am: f86d855125

Change-Id: I57d00e200ebf03010fca4ae0753200b981faaad4

core/tests/coretests/src/android/app/ApplicationErrorReportTest.java

@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2016 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
+ */
+
+package android.app;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import android.app.ApplicationErrorReport.CrashInfo;
+import android.support.test.filters.SmallTest;
+import android.support.test.runner.AndroidJUnit4;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+@RunWith(AndroidJUnit4.class)
+@SmallTest
+public class ApplicationErrorReportTest {
+
+    @Test
+    public void testHugeStacktraceLeadsToReasonableReport() {
+        Throwable deepStackTrace = deepStackTrace();
+        CrashInfo crashInfo = new CrashInfo(deepStackTrace);
+
+        assertTrue("stack trace is longer than 50'000 characters",
+                crashInfo.stackTrace.length() < 50000);
+    }
+
+    @Test
+    public void testHugeExceptionMessageLeadsToReasonableReport() {
+        StringBuilder msg = new StringBuilder();
+        for (int i = 0; i < 1000000; i++) {
+            msg.append('x');
+        }
+
+        CrashInfo crashInfo = new CrashInfo(new Throwable(msg.toString()));
+
+        assertTrue("message is longer than 50'000 characters",
+                crashInfo.exceptionMessage.length() < 50000);
+    }
+
+    @Test
+    public void testTruncationKeepsStartAndEndIntact() {
+        StringBuilder msg = new StringBuilder("start");
+        for (int i = 0; i < 1000000; i++) {
+            msg.append('x');
+        }
+        msg.append("end");
+
+        CrashInfo crashInfo = new CrashInfo(new Throwable(msg.toString()));
+
+        String exceptionMessage = crashInfo.exceptionMessage;
+        assertEquals("start", exceptionMessage.substring(0, "start".length()));
+        assertEquals("end", exceptionMessage.substring(exceptionMessage.length() - "end".length()));
+    }
+
+    /**
+     * @return a Throwable with a very long stack trace.
+     */
+    private Throwable deepStackTrace() {
+        return stackTraceGenerator__aaaaaaaaa_aaaaaaaaa_aaaaaaaaa_aaaaaaaaa_aaaaaaaaa(1000);
+    }
+
+    private Throwable stackTraceGenerator__aaaaaaaaa_aaaaaaaaa_aaaaaaaaa_aaaaaaaaa_aaaaaaaaa(
+            int d) {
+        if (d > 0) {
+            return stackTraceGenerator__aaaaaaaaa_aaaaaaaaa_aaaaaaaaa_aaaaaaaaa_aaaaaaaaa(d - 1);
+        } else {
+            return new Throwable("here");
+        }
+    }
+}