[lldb/crashlog] Replace deprecated optparse by argparse (NFC)

This patch replace the deprecated `optparse` module used for the
`crashlog`& `save_crashlog` commands with the new `argparse` from the
python standard library. This provides many benefits such as showing the
default values for each option in the help description, but also greatly
improve the handling of position arguments.

Differential Revision: https://reviews.llvm.org/D157849

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>

1 files changed, 70 insertions, 58 deletions

diff --git a/lldb/examples/python/crashlog.py b/lldb/examples/python/crashlog.py
index 1413c702f916..f91400a6c360 100755
--- a/lldb/examples/python/crashlog.py
+++ b/lldb/examples/python/crashlog.py
@@ -27,11 +27,11 @@
 # ----------------------------------------------------------------------
 
 import abc
+import argparse
 import concurrent.futures
 import contextlib
 import datetime
 import json
-import optparse
 import os
 import platform
 import plistlib
@@ -1234,12 +1234,20 @@ def usage():
 
 
 def save_crashlog(debugger, command, exe_ctx, result, dict):
-    usage = "usage: %prog [options] <output-path>"
+    usage = "save_crashlog [options] <output-path>"
     description = """Export the state of current target into a crashlog file"""
-    parser = optparse.OptionParser(
-        description=description, prog="save_crashlog", usage=usage
+    parser = argparse.ArgumentParser(
+        description=description,
+        prog="save_crashlog",
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter,
     )
-    parser.add_option(
+    parser.add_argument(
+        "output",
+        metavar="output-file",
+        type=argparse.FileType("w", encoding="utf-8"),
+        nargs=1,
+    )
+    parser.add_argument(
         "-v",
         "--verbose",
         action="store_true",
@@ -1248,21 +1256,13 @@ def save_crashlog(debugger, command, exe_ctx, result, dict):
         default=False,
     )
     try:
-        (options, args) = parser.parse_args(shlex.split(command))
-    except:
-        result.PutCString("error: invalid options")
-        return
-    if len(args) != 1:
-        result.PutCString(
-            "error: invalid arguments, a single output file is the only valid argument"
-        )
-        return
-    out_file = open(args[0], "w", encoding="utf-8")
-    if not out_file:
-        result.PutCString("error: failed to open file '%s' for writing...", args[0])
+        options = parser.parse_args(shlex.split(command))
+    except Exception as e:
+        result.SetError(str(e))
         return
     target = exe_ctx.target
     if target:
+        out_file = options.output
         identifier = target.executable.basename
         process = exe_ctx.process
         if process:
@@ -1352,7 +1352,7 @@ def save_crashlog(debugger, command, exe_ctx, result, dict):
                     )
         out_file.close()
     else:
-        result.PutCString("error: invalid target")
+        result.SetError("invalid target")
 
 
 class Symbolicate:
@@ -1366,8 +1366,8 @@ class Symbolicate:
         return "Symbolicate one or more darwin crash log files."
 
     def get_long_help(self):
-        option_parser = CrashLogOptionParser()
-        return option_parser.format_help()
+        arg_parser = CrashLogOptionParser()
+        return arg_parser.format_help()
 
 
 def SymbolicateCrashLog(crash_log, options):
@@ -1523,11 +1523,22 @@ def load_crashlog_in_scripted_process(debugger, crashlog_path, options, result):
 def CreateSymbolicateCrashLogOptions(
     command_name, description, add_interactive_options
 ):
-    usage = "usage: %prog [options] <FILE> [FILE ...]"
-    option_parser = optparse.OptionParser(
-        description=description, prog="crashlog", usage=usage
+    usage = "crashlog [options] <FILE> [FILE ...]"
+    arg_parser = argparse.ArgumentParser(
+        description=description,
+        prog="crashlog",
+        usage=usage,
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter,
+    )
+    arg_parser.add_argument(
+        "reports",
+        metavar="FILE",
+        type=str,
+        nargs="*",
+        help="crash report(s) to symbolicate",
     )
-    option_parser.add_option(
+
+    arg_parser.add_argument(
         "--version",
         "-V",
         dest="version",
@@ -1535,7 +1546,7 @@ def CreateSymbolicateCrashLogOptions(
         help="Show crashlog version",
         default=False,
     )
-    option_parser.add_option(
+    arg_parser.add_argument(
         "--verbose",
         "-v",
         action="store_true",
@@ -1543,7 +1554,7 @@ def CreateSymbolicateCrashLogOptions(
         help="display verbose debug info",
         default=False,
     )
-    option_parser.add_option(
+    arg_parser.add_argument(
         "--debug",
         "-g",
         action="store_true",
@@ -1551,7 +1562,7 @@ def CreateSymbolicateCrashLogOptions(
         help="display verbose debug logging",
         default=False,
     )
-    option_parser.add_option(
+    arg_parser.add_argument(
         "--load-all",
         "-a",
         action="store_true",
@@ -1561,22 +1572,22 @@ def CreateSymbolicateCrashLogOptions(
         "interactive mode.",
         default=False,
     )
-    option_parser.add_option(
+    arg_parser.add_argument(
         "--images",
         action="store_true",
         dest="dump_image_list",
         help="show image list",
         default=False,
     )
-    option_parser.add_option(
+    arg_parser.add_argument(
         "--debug-delay",
-        type="int",
+        type=int,
         dest="debug_delay",
         metavar="NSEC",
         help="pause for NSEC seconds for debugger",
         default=0,
     )
-    option_parser.add_option(
+    arg_parser.add_argument(
         "--crashed-only",
         "-c",
         action="store_true",
@@ -1584,15 +1595,15 @@ def CreateSymbolicateCrashLogOptions(
         help="only symbolicate the crashed thread",
         default=False,
     )
-    option_parser.add_option(
+    arg_parser.add_argument(
         "--disasm-depth",
         "-d",
-        type="int",
+        type=int,
         dest="disassemble_depth",
-        help="set the depth in stack frames that should be disassembled (default is 1)",
+        help="set the depth in stack frames that should be disassembled",
         default=1,
     )
-    option_parser.add_option(
+    arg_parser.add_argument(
         "--disasm-all",
         "-D",
         action="store_true",
@@ -1600,40 +1611,40 @@ def CreateSymbolicateCrashLogOptions(
         help="enabled disassembly of frames on all threads (not just the crashed thread)",
         default=False,
     )
-    option_parser.add_option(
+    arg_parser.add_argument(
         "--disasm-before",
         "-B",
-        type="int",
+        type=int,
         dest="disassemble_before",
         help="the number of instructions to disassemble before the frame PC",
         default=4,
     )
-    option_parser.add_option(
+    arg_parser.add_argument(
         "--disasm-after",
         "-A",
-        type="int",
+        type=int,
         dest="disassemble_after",
         help="the number of instructions to disassemble after the frame PC",
         default=4,
     )
-    option_parser.add_option(
+    arg_parser.add_argument(
         "--source-context",
         "-C",
-        type="int",
+        type=int,
         metavar="NLINES",
         dest="source_context",
-        help="show NLINES source lines of source context (default = 4)",
+        help="show NLINES source lines of source context",
         default=4,
     )
-    option_parser.add_option(
+    arg_parser.add_argument(
         "--source-frames",
-        type="int",
+        type=int,
         metavar="NFRAMES",
         dest="source_frames",
-        help="show source for NFRAMES (default = 4)",
+        help="show source for NFRAMES",
         default=4,
     )
-    option_parser.add_option(
+    arg_parser.add_argument(
         "--source-all",
         action="store_true",
         dest="source_all",
@@ -1641,28 +1652,28 @@ def CreateSymbolicateCrashLogOptions(
         default=False,
     )
     if add_interactive_options:
-        option_parser.add_option(
+        arg_parser.add_argument(
             "-i",
             "--interactive",
             action="store_true",
             help="parse a crash log and load it in a ScriptedProcess",
             default=False,
         )
-        option_parser.add_option(
+        arg_parser.add_argument(
             "-b",
             "--batch",
             action="store_true",
             help="dump symbolicated stackframes without creating a debug session",
             default=True,
         )
-        option_parser.add_option(
+        arg_parser.add_argument(
             "--target",
             "-t",
             dest="target_path",
             help="the target binary path that should be used for interactive crashlog (optional)",
             default=None,
         )
-        option_parser.add_option(
+        arg_parser.add_argument(
             "--skip-status",
             "-s",
             dest="skip_status",
@@ -1670,7 +1681,7 @@ def CreateSymbolicateCrashLogOptions(
             help="prevent the interactive crashlog to dump the process status and thread backtrace at launch",
             default=False,
         )
-    return option_parser
+    return arg_parser
 
 
 def CrashLogOptionParser():
@@ -1686,15 +1697,16 @@ be disassembled and lookups can be performed using the addresses found in the cr
 
 
 def SymbolicateCrashLogs(debugger, command_args, result, is_command):
-    option_parser = CrashLogOptionParser()
+    arg_parser = CrashLogOptionParser()
 
     if not len(command_args):
-        option_parser.print_help()
+        arg_parser.print_help()
         return
 
     try:
-        (options, args) = option_parser.parse_args(command_args)
-    except:
+        options = arg_parser.parse_args(command_args)
+    except Exception as e:
+        result.SetError(str(e))
         return
 
     # Interactive mode requires running the crashlog command from inside lldb.
@@ -1724,7 +1736,7 @@ def SymbolicateCrashLogs(debugger, command_args, result, is_command):
     if options.debug:
         print("command_args = %s" % command_args)
         print("options", options)
-        print("args", args)
+        print("args", options.reports)
 
     if options.debug_delay > 0:
         print("Waiting %u seconds for debugger to attach..." % options.debug_delay)
@@ -1743,8 +1755,8 @@ def SymbolicateCrashLogs(debugger, command_args, result, is_command):
 
     ci = debugger.GetCommandInterpreter()
 
-    if args:
-        for crashlog_file in args:
+    if options.reports:
+        for crashlog_file in options.reports:
             crashlog_path = os.path.expanduser(crashlog_file)
             if not os.path.exists(crashlog_path):
                 raise FileNotFoundError(