linter.py

#
# linter.py
# Linter for SublimeLinter3, a code checking framework for Sublime Text 3
#
# Written by Alec Thomas
# Copyright (c) 2014 Alec Thomas
#
# License: MIT
#

"""This module exports the Gometalinter plugin class."""

import os
import shlex
import tempfile

from SublimeLinter.lint import Linter, highlight, util
from SublimeLinter.lint.persist import settings


class Gometalinter(Linter):
    """Provides an interface to gometalinter."""

    cmd = 'gometalinter --fast .'
    regex = r'(?:[^:]+):(?P<line>\d+):(?P<col>\d+)?:(?:(?P<warning>warning)|(?P<error>error)):\s*(?P<message>.*)'
    error_stream = util.STREAM_BOTH
    default_type = highlight.ERROR
    defaults = {
        'selector': 'source.go'
    }

    def run(self, cmd, code):
        if settings.get('lint_mode') == 'background':
            return self._live_lint(cmd, code)
        else:
            return self._in_place_lint(cmd)

    def _live_lint(self, cmd, code):
        dir = os.path.dirname(self.filename)
        if not dir:
            print('gometalinter: skipped linting of unsaved file')
            return
        filename = os.path.basename(self.filename)
        cmd = cmd + ['-I', '^'+filename]
        print('gometalinter: live linting {} in {}: {}'.format(filename, dir, ' '.join(map(shlex.quote, cmd))))
        files = [f for f in os.listdir(dir) if f.endswith('.go')]
        if len(files) > 40:
            print("gometalinter: too many files ({}), live linting skipped".format(len(files)))
            return ''
        return self.tmpdir(cmd, dir, files, self.filename, code)

    def _in_place_lint(self, cmd):
        dir = os.path.dirname(self.filename)
        if not dir:
            print('gometalinter: skipped linting of unsaved file')
            return
        filename = os.path.basename(self.filename)
        cmd = cmd + ['-I', '^'+filename]
        print('gometalinter: in-place linting {}: {}'.format(filename, ' '.join(map(shlex.quote, cmd))))
        out = self.communicate(cmd)
        return out or ''

    def tmpdir(self, cmd, dir, files, filename, code):
        """Run an external executable using a temp dir filled with files and return its output."""
        with tempfile.TemporaryDirectory(dir=dir, prefix=".gometalinter-") as tmpdir:
            for f in files:
                target = os.path.join(tmpdir, f)
                f = os.path.join(dir, f)

                if os.path.basename(target) == os.path.basename(filename):
                    # source file hasn't been saved since change, so update it from our live buffer
                    with open(target, 'wb') as f:
                        if isinstance(code, str):
                            code = code.encode('utf8')

                        f.write(code)
                else:
                    os.link(f, target)

            out = self.communicate(cmd)
        return out or ''