bin/sort-scala-imports @ 07fbabc1f02d

#!/usr/bin/env python

import re, sys
from operator import attrgetter


bracket_padding = None
MAX_LINE_WIDTH = 100

def next_line():
    return sys.stdin.readline().rstrip('\n')

l = next_line()

while not l.startswith('import '):
    sys.stdout.write(l + '\n')
    l = next_line()

class ImportGroup(object):
    def __init__(self, line):
        self.main_line = line.rstrip()
        self.prefix = None
        self.guts = []

    def set_line(self):
        """Set the main_line and guts for the given prefix and guts.

        If the import will fit into 100 chars, the short group syntax will be
        used.  Otherwise the longer one will be used.

        """
        prefix = self.prefix
        guts = self.guts
        guts.sort(key=lambda s: s.lower())

        if not prefix:
            # This is just a single-line, single-item import, so we don't need
            # to do any setup.
            return

        single = '%s{%s%s%s}' % (prefix,
                                 bracket_padding,
                                 ', '.join(guts),
                                 bracket_padding)
        if len(single) > MAX_LINE_WIDTH:
            self.main_line = prefix + '{'
            self.guts = guts
        else:
            self.main_line = single
            self.guts = []

    def slurp(self):
        global l, bracket_padding

        line = self.main_line
        if self.main_line.endswith('}'):
            # This is a line like: import foo.{ a, b, c }
            if bracket_padding is None:
                if line[line.index("{") + 1] == " ":
                    bracket_padding = " "
                else:
                    bracket_padding = ""

            prefix, rest = line.split('{', 1)

            guts = re.findall(r"\w+ *=> *\w+|\w+", rest)

            self.prefix = prefix
            self.guts = guts

            l = next_line()
        elif line.endswith('{'):
            # This is the first line of a multi-line set
            prefix = line.rstrip('{')
            guts = []
            while True:
                l = next_line()
                if l.rstrip().endswith('}'):
                    l = next_line()
                    break
                else:
                    guts.append(l.strip().rstrip(','))

            self.prefix = prefix
            self.guts = guts
        else:
            # Just a normal single import line, pass it on.
            l = next_line()

    def spit(self):
        self.set_line()

        sys.stdout.write(self.main_line + '\n')

        if self.guts:
            self.guts.sort(key=lambda g: g.lower())
            sys.stdout.write('  ' +
                             ',\n  '.join(self.guts) +
                             '\n}\n')

    def key(self):
        return self.main_line.lower().replace('{', '@')

imports = []
while l.startswith('import '):
    ig = ImportGroup(l)
    ig.slurp()
    imports.append(ig)

if bracket_padding is None:
    bracket_padding = " "

imports.sort(key=lambda ig: ig.key())

for i in imports:
    i.spit()

sys.stdout.write(l + '\n')

for l in sys.stdin.readlines():
    sys.stdout.write(l)