Handy tool to extract filename and line number from a line of text and open vi on it

vl.py

#!/usr/bin/env python
# encoding: utf-8
import re
import os
import sys
import argparse

DESCRIPTION = """\
Try to figure out a filename and line number from the command line arguments
and start vi on it. This is handy to quickly edit a faulty line by copy and
pasting from stderr.

For example, if stderr contains this:

    file:///home/jdoe/project/source.qml:43: Unable to do assign null to QIcon
    file:///home/jdoe/project/source.qml:43: Unable to do assign null to QIcon
    file:///home/jdoe/project/source.qml:43: Unable to do assign null to QIcon

Running:

    vl file:///home/jdoe/project/source.qml:43: Unable to do assign null to QIc

or:

    vl file:///home/jdoe/project/source.qml:43:

Will open vi on /home/jdoe/project/source.qml, at line 43.

---

"""

REGEXS = [
    r"^file://(.+?):(\d+)",
    r"^(.+?):(\d+)",
    r" *File \"?(.+?)\"?, line (\d+)",
    ]

class VlException(Exception):
    pass

def parse(line):
    for rx in REGEXS:
        match = re.search(rx, line)
        if match:
            return match.group(1), match.group(2)
    raise VlException()

def edit(name, number):
    os.execlp("vi", "vi", name, "+" + number)

def main():
    parser = argparse.ArgumentParser(
        description=DESCRIPTION,
        formatter_class=argparse.RawDescriptionHelpFormatter
        )

    parser.add_argument("--dry-run", action="store_true",
        help="Just parse the line, do not launch editor")
    parser.add_argument("text", nargs=argparse.REMAINDER,
        help="Line to parse")
    args = parser.parse_args()

    text = " ".join(args.text)
    try:
        name, number = parse(text)
    except VlException:
        print "ERROR: Could not extract file name and line number from `%s`" % text
        return 1
    if args.dry_run:
        print "file: %s\nline: %s" % (name, number)
        return 0

    edit(name, number)

    return 0


if __name__ == "__main__":
    sys.exit(main())
# vi: ts=4 sw=4 et