Reapply "Import Dexter to debuginfo-tests""

This reverts commit cb935f345683194e42e6e883d79c5a16479acd74.

Discussion in D68708 advises that green dragon is being briskly
refurbished, and it's good to have this patch up testing it.

1 files changed, 299 insertions, 0 deletions

diff --git a/debuginfo-tests/dexter/dex/debugger/Debuggers.py b/debuginfo-tests/dexter/dex/debugger/Debuggers.py
new file mode 100644
index 00000000000..2f246a3fd95
--- /dev/null
+++ b/debuginfo-tests/dexter/dex/debugger/Debuggers.py
@@ -0,0 +1,299 @@
+# DExTer : Debugging Experience Tester
+# ~~~~~~   ~         ~~         ~   ~~
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+"""Discover potential/available debugger interfaces."""
+
+from collections import OrderedDict
+import os
+import pickle
+import subprocess
+import sys
+from tempfile import NamedTemporaryFile
+
+from dex.command import find_all_commands
+from dex.dextIR import DextIR
+from dex.utils import get_root_directory, Timer
+from dex.utils.Environment import is_native_windows
+from dex.utils.Exceptions import CommandParseError, DebuggerException
+from dex.utils.Exceptions import ToolArgumentError
+from dex.utils.Warning import warn
+
+from dex.debugger.dbgeng.dbgeng import DbgEng
+from dex.debugger.lldb.LLDB import LLDB
+from dex.debugger.visualstudio.VisualStudio2015 import VisualStudio2015
+from dex.debugger.visualstudio.VisualStudio2017 import VisualStudio2017
+
+
+def _get_potential_debuggers():  # noqa
+    """Return a dict of the supported debuggers.
+    Returns:
+        { name (str): debugger (class) }
+    """
+    return {
+        DbgEng.get_option_name(): DbgEng,
+        LLDB.get_option_name(): LLDB,
+        VisualStudio2015.get_option_name(): VisualStudio2015,
+        VisualStudio2017.get_option_name(): VisualStudio2017
+    }
+
+
+def _warn_meaningless_option(context, option):
+    if context.options.list_debuggers:
+        return
+
+    warn(context,
+         'option <y>"{}"</> is meaningless with this debugger'.format(option),
+         '--debugger={}'.format(context.options.debugger))
+
+
+def add_debugger_tool_base_arguments(parser, defaults):
+    defaults.lldb_executable = 'lldb.exe' if is_native_windows() else 'lldb'
+    parser.add_argument(
+        '--lldb-executable',
+        type=str,
+        metavar='<file>',
+        default=None,
+        display_default=defaults.lldb_executable,
+        help='location of LLDB executable')
+
+
+def add_debugger_tool_arguments(parser, context, defaults):
+    debuggers = Debuggers(context)
+    potential_debuggers = sorted(debuggers.potential_debuggers().keys())
+
+    add_debugger_tool_base_arguments(parser, defaults)
+
+    parser.add_argument(
+        '--debugger',
+        type=str,
+        choices=potential_debuggers,
+        required=True,
+        help='debugger to use')
+    parser.add_argument(
+        '--max-steps',
+        metavar='<int>',
+        type=int,
+        default=1000,
+        help='maximum number of program steps allowed')
+    parser.add_argument(
+        '--pause-between-steps',
+        metavar='<seconds>',
+        type=float,
+        default=0.0,
+        help='number of seconds to pause between steps')
+    defaults.show_debugger = False
+    parser.add_argument(
+        '--show-debugger',
+        action='store_true',
+        default=None,
+        help='show the debugger')
+    defaults.arch = 'x86_64'
+    parser.add_argument(
+        '--arch',
+        type=str,
+        metavar='<architecture>',
+        default=None,
+        display_default=defaults.arch,
+        help='target architecture')
+
+
+def handle_debugger_tool_base_options(context, defaults):  # noqa
+    options = context.options
+
+    if options.lldb_executable is None:
+        options.lldb_executable = defaults.lldb_executable
+    else:
+        if getattr(options, 'debugger', 'lldb') != 'lldb':
+            _warn_meaningless_option(context, '--lldb-executable')
+
+        options.lldb_executable = os.path.abspath(options.lldb_executable)
+        if not os.path.isfile(options.lldb_executable):
+            raise ToolArgumentError('<d>could not find</> <r>"{}"</>'.format(
+                options.lldb_executable))
+
+
+def handle_debugger_tool_options(context, defaults):  # noqa
+    options = context.options
+
+    handle_debugger_tool_base_options(context, defaults)
+
+    if options.arch is None:
+        options.arch = defaults.arch
+    else:
+        if options.debugger != 'lldb':
+            _warn_meaningless_option(context, '--arch')
+
+    if options.show_debugger is None:
+        options.show_debugger = defaults.show_debugger
+    else:
+        if options.debugger == 'lldb':
+            _warn_meaningless_option(context, '--show-debugger')
+
+
+def _get_command_infos(context):
+    commands = find_all_commands(context.options.source_files)
+    command_infos = OrderedDict()
+    for command_type in commands:
+        for command in commands[command_type].values():
+            if command_type not in command_infos:
+                command_infos[command_type] = []
+            command_infos[command_type].append(command)
+    return OrderedDict(command_infos)
+
+
+def empty_debugger_steps(context):
+    return DextIR(
+        executable_path=context.options.executable,
+        source_paths=context.options.source_files,
+        dexter_version=context.version)
+
+
+def get_debugger_steps(context):
+    step_collection = empty_debugger_steps(context)
+
+    with Timer('parsing commands'):
+        try:
+            step_collection.commands = _get_command_infos(context)
+        except CommandParseError as e:
+            msg = 'parser error: <d>{}({}):</> {}\n{}\n{}\n'.format(
+                e.filename, e.lineno, e.info, e.src, e.caret)
+            raise DebuggerException(msg)
+
+    with NamedTemporaryFile(
+            dir=context.working_directory.path, delete=False) as fp:
+        pickle.dump(step_collection, fp, protocol=pickle.HIGHEST_PROTOCOL)
+        steps_path = fp.name
+
+    with NamedTemporaryFile(
+            dir=context.working_directory.path, delete=False, mode='wb') as fp:
+        pickle.dump(context.options, fp, protocol=pickle.HIGHEST_PROTOCOL)
+        options_path = fp.name
+
+    dexter_py = os.path.basename(sys.argv[0])
+    if not os.path.isfile(dexter_py):
+        dexter_py = os.path.join(get_root_directory(), '..', dexter_py)
+    assert os.path.isfile(dexter_py)
+
+    with NamedTemporaryFile(dir=context.working_directory.path) as fp:
+        args = [
+            sys.executable, dexter_py, 'run-debugger-internal-', steps_path,
+            options_path, '--working-directory', context.working_directory.path,
+            '--unittest=off', '--indent-timer-level={}'.format(Timer.indent + 2)
+        ]
+        try:
+            with Timer('running external debugger process'):
+                subprocess.check_call(args)
+        except subprocess.CalledProcessError as e:
+            raise DebuggerException(e)
+
+    with open(steps_path, 'rb') as fp:
+        step_collection = pickle.load(fp)
+
+    return step_collection
+
+
+class Debuggers(object):
+    @classmethod
+    def potential_debuggers(cls):
+        try:
+            return cls._potential_debuggers
+        except AttributeError:
+            cls._potential_debuggers = _get_potential_debuggers()
+            return cls._potential_debuggers
+
+    def __init__(self, context):
+        self.context = context
+
+    def load(self, key, step_collection=None):
+        with Timer('load {}'.format(key)):
+            return Debuggers.potential_debuggers()[key](self.context,
+                                                        step_collection)
+
+    def _populate_debugger_cache(self):
+        debuggers = []
+        for key in sorted(Debuggers.potential_debuggers()):
+            debugger = self.load(key)
+
+            class LoadedDebugger(object):
+                pass
+
+            LoadedDebugger.option_name = key
+            LoadedDebugger.full_name = '[{}]'.format(debugger.name)
+            LoadedDebugger.is_available = debugger.is_available
+
+            if LoadedDebugger.is_available:
+                try:
+                    LoadedDebugger.version = debugger.version.splitlines()
+                except AttributeError:
+                    LoadedDebugger.version = ['']
+            else:
+                try:
+                    LoadedDebugger.error = debugger.loading_error.splitlines()
+                except AttributeError:
+                    LoadedDebugger.error = ['']
+
+                try:
+                    LoadedDebugger.error_trace = debugger.loading_error_trace
+                except AttributeError:
+                    LoadedDebugger.error_trace = None
+
+            debuggers.append(LoadedDebugger)
+        return debuggers
+
+    def list(self):
+        debuggers = self._populate_debugger_cache()
+
+        max_o_len = max(len(d.option_name) for d in debuggers)
+        max_n_len = max(len(d.full_name) for d in debuggers)
+
+        msgs = []
+
+        for d in debuggers:
+            # Option name, right padded with spaces for alignment
+            option_name = (
+                '{{name: <{}}}'.format(max_o_len).format(name=d.option_name))
+
+            # Full name, right padded with spaces for alignment
+            full_name = ('{{name: <{}}}'.format(max_n_len)
+                         .format(name=d.full_name))
+
+            if d.is_available:
+                name = '<b>{} {}</>'.format(option_name, full_name)
+
+                # If the debugger is available, show the first line of the
+                #  version info.
+                available = '<g>YES</>'
+                info = '<b>({})</>'.format(d.version[0])
+            else:
+                name = '<y>{} {}</>'.format(option_name, full_name)
+
+                # If the debugger is not available, show the first line of the
+                # error reason.
+                available = '<r>NO</> '
+                info = '<y>({})</>'.format(d.error[0])
+
+            msg = '{} {} {}'.format(name, available, info)
+
+            if self.context.options.verbose:
+                # If verbose mode and there was more version or error output
+                # than could be displayed in a single line, display the whole
+                # lot slightly indented.
+                verbose_info = None
+                if d.is_available:
+                    if d.version[1:]:
+                        verbose_info = d.version + ['\n']
+                else:
+                    # Some of list elems may contain multiple lines, so make
+                    # sure each elem is a line of its own.
+                    verbose_info = d.error_trace
+
+                if verbose_info:
+                    verbose_info = '\n'.join('        {}'.format(l.rstrip())
+                                             for l in verbose_info) + '\n'
+                    msg = '{}\n\n{}'.format(msg, verbose_info)
+
+            msgs.append(msg)
+        self.context.o.auto('\n{}\n\n'.format('\n'.join(msgs)))