Escapes in MI error records are mangled

[barisione]

Describe the bug

When parsing an error record, backslashes are just dropped. This works for quotes but mangles other escapes (like \n).

For instance this:

^error,msg="This is an error\non multiple lines and with\tother escapes"

Becomes a dictionary with this message:

This is an errornon multiple lines and withtother escapes

To Reproduce

I wrote a simple script.py Python script with a GDB command to be able to have arbitrary escapes:

import gdb


class MyCommand(gdb.Command):
    def __init__(self):
        super().__init__("my-command", gdb.COMMAND_NONE)

    def invoke(self, args, from_tty):
        raise gdb.GdbError("This is an error\non multiple lines and with\tother escapes")


MyCommand()

Start GDB in MI-mode and load the script:

gdb -i=mi2 -x script.py

When you use the command, GDB produces this output:

(gdb)
my-command
&"my-command\n"
&"This is an error\n"
&"on multiple lines and with\tother escapes\n"
^error,msg="This is an error\non multiple lines and with\tother escapes"

Parse it with pygdbmi:

gdbmiparser.parse_response(r'^error,msg="This is an error\non multiple lines and with\tother escapes"')

And you get:

{'type': 'result',
 'message': 'error',
 'payload': {'msg': 'This is an errornon multiple lines and withtother escapes'},
 'token': None}

Expected behavior

Escapes should be interpreted. In the example above I would expect this output:

{'type': 'result',
 'message': 'error',
 'payload': {'msg': 'This is an error\non multiple lines and with\tother escapes'},
 'token': None}

The correct escape behaviour (which is not compatible with Python escapes) can be found in printchar in gdb/utils.c in the binutils-gdb repository.

Please complete the following information:

• OS: macOS
• pygdbmi version (pip freeze output):

$ pip freeze | grep pygdbmi
pygdbmi==0.10.0.1

Additional context

I haven't looked at the pygdbmi code yet but I may be able to make a PR if you are interested. I already have an unescape function in Python.

[cs01]

Thanks for the report. Yes if you'd like to make a PR that would be appreciated!

[barisione]

Thanks for the report. Yes if you'd like to make a PR that would be appreciated!

Here we go: #59 (not sure if you receive notifications for PRs).

[cs01]

Thanks, yes I do. I appreciate the PR. I’ll review it as soon as possible. I have a lot of obligations in my personal life at the moment but I will get to it within the next 7 days.