scripts/stack_core.py

#!/usr/bin/env python3
#
# Copyright (C) 2013 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.

"""stack symbolizes native crash dumps."""

import os
import re
import subprocess
import symbol
import tempfile
import unittest

import example_crashes

def ConvertTrace(lines):
  tracer = TraceConverter()
  print("Reading symbols from", symbol.SYMBOLS_DIR)
  tracer.ConvertTrace(lines)

class TraceConverter:
  process_info_line = re.compile(r"(pid: [0-9]+, tid: [0-9]+.*)")
  revision_line = re.compile(r"(Revision: '(.*)')")
  signal_line = re.compile(r"(signal [0-9]+ \(.*\).*)")
  abort_message_line = re.compile(r"(Abort message: '.*')")
  thread_line = re.compile(r"(.*)(--- ){15}---")
  dalvik_jni_thread_line = re.compile("(\".*\" prio=[0-9]+ tid=[0-9]+ NATIVE.*)")
  dalvik_native_thread_line = re.compile("(\".*\" sysTid=[0-9]+ nice=[0-9]+.*)")
  register_line = re.compile("$a")
  trace_line = re.compile("$a")
  sanitizer_trace_line = re.compile("$a")
  value_line = re.compile("$a")
  code_line = re.compile("$a")
  zipinfo_central_directory_line = re.compile(r"Central\s+directory\s+entry")
  zipinfo_central_info_match = re.compile(
      r"^\s*(\S+)$\s*offset of local header from start of archive:\s*(\d+)"
      r".*^\s*compressed size:\s+(\d+)", re.M | re.S)
  unreachable_line = re.compile(r"((\d+ bytes in \d+ unreachable allocations)|"
                                r"(\d+ bytes unreachable at [0-9a-f]+)|"
                                r"(referencing \d+ unreachable bytes in \d+ allocation(s)?)|"
                                r"(and \d+ similar unreachable bytes in \d+ allocation(s)?))")
  trace_lines = []
  value_lines = []
  last_frame = -1
  width = "{8}"
  spacing = ""
  apk_info = dict()

  register_names = {
    "arm": "r0|r1|r2|r3|r4|r5|r6|r7|r8|r9|sl|fp|ip|sp|lr|pc|cpsr",
    "arm64": "x0|x1|x2|x3|x4|x5|x6|x7|x8|x9|x10|x11|x12|x13|x14|x15|x16|x17|x18|x19|x20|x21|x22|x23|x24|x25|x26|x27|x28|x29|x30|sp|pc|pstate",
    "mips": "zr|at|v0|v1|a0|a1|a2|a3|t0|t1|t2|t3|t4|t5|t6|t7|s0|s1|s2|s3|s4|s5|s6|s7|t8|t9|k0|k1|gp|sp|s8|ra|hi|lo|bva|epc",
    "mips64": "zr|at|v0|v1|a0|a1|a2|a3|a4|a5|a6|a7|t0|t1|t2|t3|s0|s1|s2|s3|s4|s5|s6|s7|t8|t9|k0|k1|gp|sp|s8|ra|hi|lo|bva|epc",
    "x86": "eax|ebx|ecx|edx|esi|edi|x?cs|x?ds|x?es|x?fs|x?ss|eip|ebp|esp|flags",
    "x86_64": "rax|rbx|rcx|rdx|rsi|rdi|r8|r9|r10|r11|r12|r13|r14|r15|cs|ss|rip|rbp|rsp|eflags",
  }

  def UpdateAbiRegexes(self):
    if symbol.ARCH == "arm64" or symbol.ARCH == "mips64" or symbol.ARCH == "x86_64":
      self.width = "{16}"
      self.spacing = "        "
    else:
      self.width = "{8}"
      self.spacing = ""

    self.register_line = re.compile("(([ ]*\\b(" + self.register_names[symbol.ARCH] + ")\\b +[0-9a-f]" + self.width + "){2,5})")

    # Note that both trace and value line matching allow for variable amounts of
    # whitespace (e.g. \t). This is because the we want to allow for the stack
    # tool to operate on AndroidFeedback provided system logs. AndroidFeedback
    # strips out double spaces that are found in tombsone files and logcat output.
    #
    # Examples of matched trace lines include lines from tombstone files like:
    #   #00  pc 001cf42e  /data/data/com.my.project/lib/libmyproject.so
    #
    # Or lines from AndroidFeedback crash report system logs like:
    #   03-25 00:51:05.520 I/DEBUG ( 65): #00 pc 001cf42e /data/data/com.my.project/lib/libmyproject.so
    # Please note the spacing differences.
    self.trace_line = re.compile(
        r".*"                                                 # Random start stuff.
        r"\#(?P<frame>[0-9]+)"                                # Frame number.
        r"[ \t]+..[ \t]+"                                     # (space)pc(space).
        r"(?P<offset>[0-9a-f]" + self.width + ")[ \t]+"       # Offset (hex number given without
                                                              #         0x prefix).
        r"(?P<dso>\[[^\]]+\]|[^\r\n \t]*)"                    # Library name.
        r"( \(offset (?P<so_offset>0x[0-9a-fA-F]+)\))?"       # Offset into the file to find the start of the shared so.
        r"(?P<symbolpresent> \((?P<symbol>.*)\))?")           # Is the symbol there?
                                                              # pylint: disable-msg=C6310
    # Sanitizer output. This is different from debuggerd output, and it is easier to handle this as
    # its own regex. Example:
    # 08-19 05:29:26.283   397   403 I         :     #0 0xb6a15237  (/system/lib/libclang_rt.asan-arm-android.so+0x4f237)
    self.sanitizer_trace_line = re.compile(
        r".*"                                                 # Random start stuff.
        r"\#(?P<frame>[0-9]+)"                                # Frame number.
        r"[ \t]+0x[0-9a-f]+[ \t]+"                            # PC, not interesting to us.
        r"\("                                                 # Opening paren.
        r"(?P<dso>[^+]+)"                                     # Library name.
        r"\+"                                                 # '+'
        r"0x(?P<offset>[0-9a-f]+)"                            # Offset (hex number given with
                                                              #         0x prefix).
        r"\)")                                                # Closing paren.
                                                              # pylint: disable-msg=C6310
    # Examples of matched value lines include:
    #   bea4170c  8018e4e9  /data/data/com.my.project/lib/libmyproject.so
    #   bea4170c  8018e4e9  /data/data/com.my.project/lib/libmyproject.so (symbol)
    #   03-25 00:51:05.530 I/DEBUG ( 65): bea4170c 8018e4e9 /data/data/com.my.project/lib/libmyproject.so
    # Again, note the spacing differences.
    self.value_line = re.compile(r"(.*)([0-9a-f]" + self.width + r")[ \t]+([0-9a-f]" + self.width + r")[ \t]+([^\r\n \t]*)( \((.*)\))?")
    # Lines from 'code around' sections of the output will be matched before
    # value lines because otheriwse the 'code around' sections will be confused as
    # value lines.
    #
    # Examples include:
    #   801cf40c ffffc4cc 00b2f2c5 00b2f1c7 00c1e1a8
    #   03-25 00:51:05.530 I/DEBUG ( 65): 801cf40c ffffc4cc 00b2f2c5 00b2f1c7 00c1e1a8
    self.code_line = re.compile(r"(.*)[ \t]*[a-f0-9]" + self.width +
                                r"[ \t]*[a-f0-9]" + self.width +
                                r"[ \t]*[a-f0-9]" + self.width +
                                r"[ \t]*[a-f0-9]" + self.width +
                                r"[ \t]*[a-f0-9]" + self.width +
                                r"[ \t]*[ \r\n]")  # pylint: disable-msg=C6310

  def CleanLine(self, ln):
    # AndroidFeedback adds zero width spaces into its crash reports. These
    # should be removed or the regular expresssions will fail to match.
    return ln.encode().decode(encoding='utf8', errors='ignore')

  def PrintTraceLines(self, trace_lines):
    """Print back trace."""
    maxlen = max(len(tl[1]) for tl in trace_lines)
    print("\nStack Trace:")
    print("  RELADDR   " + self.spacing + "FUNCTION".ljust(maxlen) + "  FILE:LINE")
    for tl in self.trace_lines:
      (addr, symbol_with_offset, location) = tl
      print("  %8s  %s  %s" % (addr, symbol_with_offset.ljust(maxlen), location))

  def PrintValueLines(self, value_lines):
    """Print stack data values."""
    maxlen = max(len(tl[2]) for tl in self.value_lines)
    print("\nStack Data:")
    print("  ADDR      " + self.spacing + "VALUE     " + "FUNCTION".ljust(maxlen) + "  FILE:LINE")
    for vl in self.value_lines:
      (addr, value, symbol_with_offset, location) = vl
      print("  %8s  %8s  %s  %s" % (addr, value, symbol_with_offset.ljust(maxlen), location))

  def PrintOutput(self, trace_lines, value_lines):
    if self.trace_lines:
      self.PrintTraceLines(self.trace_lines)
    if self.value_lines:
      self.PrintValueLines(self.value_lines)

  def PrintDivider(self):
    print("\n-----------------------------------------------------\n")

  def DeleteApkTmpFiles(self):
    for _, _, tmp_files in self.apk_info.values():
      for tmp_file in tmp_files.values():
        os.unlink(tmp_file)

  def ConvertTrace(self, lines):
    lines = [self.CleanLine(line) for line in lines]
    try:
      if not symbol.ARCH:
        symbol.SetAbi(lines)
      self.UpdateAbiRegexes()
      for line in lines:
        self.ProcessLine(line)
      self.PrintOutput(self.trace_lines, self.value_lines)
    finally:
      # Delete any temporary files created while processing the lines.
      self.DeleteApkTmpFiles()

  def MatchTraceLine(self, line):
    if self.trace_line.match(line):
      match = self.trace_line.match(line)
      return {"frame": match.group("frame"),
              "offset": match.group("offset"),
              "so_offset": match.group("so_offset"),
              "dso": match.group("dso"),
              "symbol_present": bool(match.group("symbolpresent")),
              "symbol_name": match.group("symbol")}
    if self.sanitizer_trace_line.match(line):
      match = self.sanitizer_trace_line.match(line)
      return {"frame": match.group("frame"),
              "offset": match.group("offset"),
              "so_offset": None,
              "dso": match.group("dso"),
              "symbol_present": False,
              "symbol_name": None}
    return None

  def ExtractLibFromApk(self, apk, shared_lib_name):
    # Create a temporary file containing the shared library from the apk.
    tmp_file = None
    try:
      tmp_fd, tmp_file = tempfile.mkstemp()
      if subprocess.call(["unzip", "-p", apk, shared_lib_name], stdout=tmp_fd) == 0:
        os.close(tmp_fd)
        shared_file = tmp_file
        tmp_file = None
        return shared_file
    finally:
      if tmp_file:
        os.close(tmp_fd)
        os.unlink(tmp_file)
    return None

  def ProcessCentralInfo(self, offset_list, central_info):
    match = self.zipinfo_central_info_match.search(central_info)
    if not match:
      raise Exception("Cannot find all info from zipinfo\n" + central_info)
    name = match.group(1)
    start = int(match.group(2))
    end = start + int(match.group(3))

    offset_list.append([name, start, end])
    return name, start, end

  def GetLibFromApk(self, apk, offset):
    # Convert the string to hex.
    offset = int(offset, 16)

    # Check if we already have information about this offset.
    if apk in self.apk_info:
      apk_full_path, offset_list, tmp_files = self.apk_info[apk]
      for file_name, start, end in offset_list:
        if offset >= start and offset < end:
          if file_name in tmp_files:
            return file_name, tmp_files[file_name]
          tmp_file = self.ExtractLibFromApk(apk_full_path, file_name)
          if tmp_file:
            tmp_files[file_name] = tmp_file
            return file_name, tmp_file
          break
      return None, None

    if not "ANDROID_PRODUCT_OUT" in os.environ:
      print("ANDROID_PRODUCT_OUT environment variable not set.")
      return None, None
    out_dir = os.environ["ANDROID_PRODUCT_OUT"]
    if not os.path.exists(out_dir):
      print("ANDROID_PRODUCT_OUT", out_dir, "does not exist.")
      return None, None
    if apk.startswith("/"):
      apk_full_path = out_dir + apk
    else:
      apk_full_path = os.path.join(out_dir, apk)
    if not os.path.exists(apk_full_path):
      print("Cannot find apk", apk)
      return None, None

    cmd = subprocess.Popen(["zipinfo", "-v", apk_full_path], stdout=subprocess.PIPE,
                           encoding='utf8')
    # Find the first central info marker.
    for line in cmd.stdout:
      if self.zipinfo_central_directory_line.search(line):
        break

    central_info = ""
    file_name = None
    offset_list = []
    for line in cmd.stdout:
      match = self.zipinfo_central_directory_line.search(line)
      if match:
        cur_name, start, end = self.ProcessCentralInfo(offset_list, central_info)
        if not file_name and offset >= start and offset < end:
          file_name = cur_name
        central_info = ""
      else:
        central_info += line
    if central_info:
      cur_name, start, end = self.ProcessCentralInfo(offset_list, central_info)
      if not file_name and offset >= start and offset < end:
        file_name = cur_name

    # Make sure the offset_list is sorted, the zip file does not guarantee
    # that the entries are in order.
    offset_list = sorted(offset_list, key=lambda entry: entry[1])

    # Save the information from the zip.
    tmp_files = dict()
    self.apk_info[apk] = [apk_full_path, offset_list, tmp_files]
    if not file_name:
      return None, None
    tmp_shared_lib = self.ExtractLibFromApk(apk_full_path, file_name)
    if tmp_shared_lib:
      tmp_files[file_name] = tmp_shared_lib
      return file_name, tmp_shared_lib
    return None, None

  def GetLibPath(self, lib):
    symbol_dir = symbol.SYMBOLS_DIR
    if os.path.isfile(symbol_dir + lib):
      return lib

    # When using atest, test paths are different between the out/ directory
    # and device. Apply fixups.
    if not lib.startswith("/data/local/tests/") and not lib.startswith("/data/local/tmp/"):
      print("WARNING: Cannot find %s in symbol directory" % lib)
      return lib

    test_name = lib.rsplit("/", 1)[-1]
    test_dir = "/data/nativetest"
    test_dir_bitness = ""
    if symbol.ARCH.endswith("64"):
      bitness = "64"
      test_dir_bitness = "64"
    else:
      bitness = "32"

    # Unfortunately, the location of the real symbol file is not
    # standardized, so we need to go hunting for it.

    # This is in vendor, look for the value in:
    #   /data/nativetest{64}/vendor/test_name/test_name
    if lib.startswith("/data/local/tests/vendor/"):
       lib_path = os.path.join(test_dir + test_dir_bitness, "vendor", test_name, test_name)
       if os.path.isfile(symbol_dir + lib_path):
         return lib_path

    # Look for the path in:
    #   /data/nativetest{64}/test_name/test_name
    lib_path = os.path.join(test_dir + test_dir_bitness, test_name, test_name)
    if os.path.isfile(symbol_dir + lib_path):
      return lib_path

    # CtsXXX tests are in really non-standard locations try:
    #  /data/nativetest/{test_name}
    lib_path = os.path.join(test_dir, test_name)
    if os.path.isfile(symbol_dir + lib_path):
      return lib_path
    # Try:
    #   /data/nativetest/{test_name}{32|64}
    lib_path += bitness
    if os.path.isfile(symbol_dir + lib_path):
      return lib_path

    # Cannot find location, give up and return the original path
    print("WARNING: Cannot find %s in symbol directory" % lib)
    return lib


  def ProcessLine(self, line):
    ret = False
    process_header = self.process_info_line.search(line)
    signal_header = self.signal_line.search(line)
    abort_message_header = self.abort_message_line.search(line)
    thread_header = self.thread_line.search(line)
    register_header = self.register_line.search(line)
    revision_header = self.revision_line.search(line)
    dalvik_jni_thread_header = self.dalvik_jni_thread_line.search(line)
    dalvik_native_thread_header = self.dalvik_native_thread_line.search(line)
    unreachable_header = self.unreachable_line.search(line)
    if process_header or signal_header or abort_message_header or thread_header or \
        register_header or dalvik_jni_thread_header or dalvik_native_thread_header or \
        revision_header or unreachable_header:
      ret = True
      if self.trace_lines or self.value_lines:
        self.PrintOutput(self.trace_lines, self.value_lines)
        self.PrintDivider()
        self.trace_lines = []
        self.value_lines = []
        self.last_frame = -1
      if process_header:
        print(process_header.group(1))
      if signal_header:
        print(signal_header.group(1))
      if abort_message_header:
        print(abort_message_header.group(1))
      if register_header:
        print(register_header.group(1))
      if thread_header:
        print(thread_header.group(1))
      if dalvik_jni_thread_header:
        print(dalvik_jni_thread_header.group(1))
      if dalvik_native_thread_header:
        print(dalvik_native_thread_header.group(1))
      if revision_header:
        print(revision_header.group(1))
      if unreachable_header:
        print(unreachable_header.group(1))
      return True
    trace_line_dict = self.MatchTraceLine(line)
    if trace_line_dict is not None:
      ret = True
      frame = int(trace_line_dict["frame"])
      code_addr = trace_line_dict["offset"]
      area = trace_line_dict["dso"]
      so_offset = trace_line_dict["so_offset"]
      symbol_present = trace_line_dict["symbol_present"]
      symbol_name = trace_line_dict["symbol_name"]

      if frame <= self.last_frame and (self.trace_lines or self.value_lines):
        self.PrintOutput(self.trace_lines, self.value_lines)
        self.PrintDivider()
        self.trace_lines = []
        self.value_lines = []
      self.last_frame = frame

      if area == "<unknown>" or area == "[heap]" or area == "[stack]":
        self.trace_lines.append((code_addr, "", area))
      else:
        # If this is an apk, it usually means that there is actually
        # a shared so that was loaded directly out of it. In that case,
        # extract the shared library and the name of the shared library.
        lib = None
        # The format of the map name:
        #   Some.apk!libshared.so
        # or
        #   Some.apk
        if so_offset:
          # If it ends in apk, we are done.
          apk = None
          if area.endswith(".apk"):
            apk = area
          else:
            index = area.rfind(".so!")
            if index != -1:
              # Sometimes we'll see something like:
              #   #01 pc abcd  libart.so!libart.so (offset 0x134000)
              # Remove everything after the ! and zero the offset value.
              area = area[0:index + 3]
              so_offset = 0
            else:
              index = area.rfind(".apk!")
              if index != -1:
                apk = area[0:index + 4]
          if apk:
            lib_name, lib = self.GetLibFromApk(apk, so_offset)
        if not lib:
          lib = area
          lib_name = None

        # When using atest, test paths are different between the out/ directory
        # and device. Apply fixups.
        lib = self.GetLibPath(lib)

        # If a calls b which further calls c and c is inlined to b, we want to
        # display "a -> b -> c" in the stack trace instead of just "a -> c"
        info = symbol.SymbolInformation(lib, code_addr)
        nest_count = len(info) - 1
        for (source_symbol, source_location, object_symbol_with_offset) in info:
          if not source_symbol:
            if symbol_present:
              source_symbol = symbol.CallCppFilt(symbol_name)
            else:
              source_symbol = "<unknown>"
          if not source_location:
            source_location = area
            if lib_name:
              source_location += "(" + lib_name + ")"
          if nest_count > 0:
            nest_count = nest_count - 1
            arrow = "v------>"
            if symbol.ARCH == "arm64" or symbol.ARCH == "mips64" or symbol.ARCH == "x86_64":
              arrow = "v-------------->"
            self.trace_lines.append((arrow, source_symbol, source_location))
          else:
            if not object_symbol_with_offset:
              object_symbol_with_offset = source_symbol
            self.trace_lines.append((code_addr,
                                object_symbol_with_offset,
                                source_location))
    if self.code_line.match(line):
      # Code lines should be ignored. If this were exluded the 'code around'
      # sections would trigger value_line matches.
      return ret
    if self.value_line.match(line):
      ret = True
      match = self.value_line.match(line)
      (unused_, addr, value, area, symbol_present, symbol_name) = match.groups()
      if area == "<unknown>" or area == "[heap]" or area == "[stack]" or not area:
        self.value_lines.append((addr, value, "", area))
      else:
        info = symbol.SymbolInformation(area, value)
        (source_symbol, source_location, object_symbol_with_offset) = info.pop()
        # If there is no information, skip this.
        if source_symbol or source_location or object_symbol_with_offset:
          if not source_symbol:
            if symbol_present:
              source_symbol = symbol.CallCppFilt(symbol_name)
            else:
              source_symbol = "<unknown>"
          if not source_location:
            source_location = area
          if not object_symbol_with_offset:
            object_symbol_with_offset = source_symbol
          self.value_lines.append((addr,
                                   value,
                                   object_symbol_with_offset,
                                   source_location))

    return ret


class RegisterPatternTests(unittest.TestCase):
  def assert_register_matches(self, abi, example_crash, stupid_pattern):
    tc = TraceConverter()
    lines = example_crash.split('\n')
    symbol.SetAbi(lines)
    tc.UpdateAbiRegexes()
    for line in lines:
      tc.ProcessLine(line)
      is_register = (re.search(stupid_pattern, line) is not None)
      matched = (tc.register_line.search(line) is not None)
      self.assertEqual(matched, is_register, line)
    tc.PrintOutput(tc.trace_lines, tc.value_lines)

  def test_arm_registers(self):
    self.assert_register_matches("arm", example_crashes.arm, '\\b(r0|r4|r8|ip)\\b')

  def test_arm64_registers(self):
    self.assert_register_matches("arm64", example_crashes.arm64, '\\b(x0|x4|x8|x12|x16|x20|x24|x28|sp)\\b')

  def test_mips_registers(self):
    self.assert_register_matches("mips", example_crashes.mips, '\\b(zr|a0|t0|t4|s0|s4|t8|gp|hi)\\b')

  def test_mips64_registers(self):
    self.assert_register_matches("mips64", example_crashes.mips64, '\\b(zr|a0|a4|t0|s0|s4|t8|gp|hi)\\b')

  def test_x86_registers(self):
    self.assert_register_matches("x86", example_crashes.x86, '\\b(eax|esi|xcs|eip)\\b')

  def test_x86_64_registers(self):
    self.assert_register_matches("x86_64", example_crashes.x86_64, '\\b(rax|rsi|r8|r12|cs|rip)\\b')

class LibmemunreachablePatternTests(unittest.TestCase):
  def test_libmemunreachable(self):
    tc = TraceConverter()
    lines = example_crashes.libmemunreachable.split('\n')

    symbol.SetAbi(lines)
    self.assertEqual(symbol.ARCH, "arm")

    tc.UpdateAbiRegexes()
    header_lines = 0
    trace_lines = 0
    for line in lines:
      tc.ProcessLine(line)
      if re.search(tc.unreachable_line, line) is not None:
        header_lines += 1
      if tc.MatchTraceLine(line) is not None:
        trace_lines += 1
    self.assertEqual(header_lines, 3)
    self.assertEqual(trace_lines, 2)
    tc.PrintOutput(tc.trace_lines, tc.value_lines)

class LongASANStackTests(unittest.TestCase):
  # Test that a long ASAN-style (non-padded frame numbers) stack trace is not split into two
  # when the frame number becomes two digits. This happened before as the frame number was
  # handled as a string and not converted to an integral.
  def test_long_asan_crash(self):
    tc = TraceConverter()
    lines = example_crashes.long_asan_crash.splitlines()
    symbol.SetAbi(lines)
    tc.UpdateAbiRegexes()
    # Test by making sure trace_line_count is monotonically non-decreasing. If the stack trace
    # is split, a separator is printed and trace_lines is flushed.
    trace_line_count = 0
    for line in lines:
      tc.ProcessLine(line)
      self.assertLessEqual(trace_line_count, len(tc.trace_lines))
      trace_line_count = len(tc.trace_lines)
    # The split happened at transition of frame #9 -> #10. Make sure we have parsed (and stored)
    # more than ten frames.
    self.assertGreater(trace_line_count, 10)
    tc.PrintOutput(tc.trace_lines, tc.value_lines)

class ValueLinesTest(unittest.TestCase):
  def test_value_line_skipped(self):
    tc = TraceConverter()
    symbol.SetAbi(["ABI: 'arm'"])
    tc.UpdateAbiRegexes()
    tc.ProcessLine("    12345678  00001000  .")
    self.assertEqual([], tc.value_lines)

if __name__ == '__main__':
    unittest.main(verbosity=2)