@Test
public void testStackFrameMatcher() {

  String[] validFrames = new String[] {
    "at com.example.t1.MainActivity.one(MainActivity.java:31)",
    "      at android.app.ActivityThread.access$700(ActivityThread.java:134)",
    "\tat java.lang.reflect.Method.invokeNative(Native Method)",
  };
  for (String frame: validFrames) {
    assertThat(StackTraceExpander.getStackLine(frame)).isEqualTo(frame.trim());
  }
  String[] invalidFrames = new String[] {
    "Caused by: java.lang.RuntimeException",
    "... 15 more"
  };
  for (String frame: invalidFrames) {
    Assert.assertNull(StackTraceExpander.getStackLine(frame));
  }
}