pmacs3/mode/scala.py

from tab import StackTabber2
from mode import Fundamental
from lex import Grammar, PatternRule, RegionRule, PatternMatchRule
from mode.xml import XMLGrammar
from mode.pipe import Pipe
from method.shell import Interact

chr1 = '[a-zA-Z_]'
chr2 = '[a-zA-Z_0-9]'
word = chr1 + chr2 + '*'

class NestedCommentGrammar(Grammar): pass
NestedCommentGrammar.rules = [
    RegionRule('comment', r'/\*', NestedCommentGrammar, r'\*/'),
    PatternRule('data', r'(?:[^\*]|\*(?!/))+'),
]

class StringGrammar(Grammar):
    rules = [
        PatternRule('escaped', r"\\u[0-9A-Fa-f]{4}|\\[0-7]{1,3}|\\[btnfr\"'\\]"),
        PatternRule('data', r'[^\\"]+'),
    ]

class ScalaGrammar(Grammar):
    rules = [
        PatternRule('scala.comment', '//.*$'),
        RegionRule('scala.comment', r'/\*', NestedCommentGrammar, r'\*/'),

        PatternRule('delimiter', r'(?:;|{|}|\[|\]|\(|\)|,|\.|<(?![a-zA-Z_])|>|:|/|\+|-|\*|=)'),

        PatternRule('spaces', r'(?:\t| )+'),
        PatternRule('eol', r'\n'),

        PatternRule('scala.def', '(?<=(?<![a-zA-Z0-9_])def )[a-zA-Z_][a-zA-Z0-9_]*'),
        PatternRule('scala.class', '(?<=(?<![a-zA-Z0-9_])class )[a-zA-Z_][a-zA-Z0-9_]*'),
        PatternRule('scala.class', '(?<=(?<![a-zA-Z0-9_])object )[a-zA-Z_][a-zA-Z0-9_]*'),

        PatternRule('scala.reserved', '(?:yield|with|while|var|val|type|true|try|trait|throw|this|super|sealed|return|protected|private|package|override|object|null|new|match|lazy|import|implicit|if|forSome|for|finally|final|false|extends|else|do|def|class|catch|case|abstract)(?!%s)' % word),

        PatternRule('scala.integer', '-?(?:0|[1-9])[0-9]*[Ll]?'),
        PatternRule('scala.integer', '-?0x[0-9A-Fa-f]+[Ll]?'),
        PatternRule('scala.integer', '-?0[0-7]+[Ll]?'),

        PatternRule('scala.float', r'-?[0-9]+\.[0-9]*'), # FIXME

        PatternRule('scala.bool', '(?:true|false)(?![a-zA-Z0-9_])'),

        PatternRule('scala.char', r"'(?:[^'\\]|\\u[0-9A-Fa-f]{4}|\\[0-7]{1,3}|\\[btnfr\"'\\])'"),
        RegionRule('scala.string', '"', StringGrammar, '"'),
        PatternRule('scala.symbol', "'[a-zA-Z_][a-zA-Z0-9_]*"),

        PatternRule('scala.annotation', '@[a-zA-Z_][a-zA-Z0-9_]*'),
        PatternRule('scala.bareword', '[a-zA-Z_][a-zA-Z0-9_]*'),
        PatternRule('scala.null', 'null'),

        RegionRule('scala.inline', r'(?:^| )(?=<[a-zA-Z_])', XMLGrammar, '^[ \t]*$'),
    ]

class ScalaTabber(StackTabber2):
    open_tokens        = {'delimiter': {'{': '}', '(': ')', '[': ']'}}
    close_tokens       = {'delimiter': {'}': '{', ')': '(', ']': '['}}
    control_tokens     = {'scala.reserved': set(('if', 'else', 'while', 'do', 'for'))}
    end_at_eof         = True
    start_free_tokens  = {'string.start': 'string.end'}
    end_free_tokens    = {'string.end': 'string.start'}
    is_ignored_tokens  = set(('spaces', 'eol', 'comment', 'comment.start',
                              'comment.data', 'comment.null', 'comment.end'))
    is_indent_tokens   = set(('spaces',))
    def _is_base(self, y):
        # the first line is always safe
        if y == 0: return True

        # if there are no tokens we don't really have any info
        tokens = self._get_tokens(y)
        if not tokens: return False

        # if it looks like a top-level class, object or function, then say ok
        t = tokens[0]
        if t.fqmatchs('scala.reserved', ('class', 'object', 'def')):
            return True

        # the default is to assume no
        return False

class ScalaStart(Interact):
    args = []
    modename = 'scalapipe'
    reuse = True
    def _execute(self, w, **vargs):
        Interact._execute(self, w, bname='*Scala*', cmd='scala')

class Scala(Fundamental):
    name        = 'Scala'
    extensions  = ['.scala']
    tabwidth    = 2
    tabbercls   = ScalaTabber
    grammar     = ScalaGrammar
    commentc    = '//'
    actions     = [ScalaStart]
    opentokens  = ('delimiter',)
    opentags    = {'(': ')', '[': ']', '{': '}'}
    closetokens = ('delimiter',)
    closetags   = {')': '(', ']': '[', '}': '{'}

    colors      = {
        'scala.annotation': ('magenta', 'default'),
        'scala.bool':       ('magenta', 'default'),
        'scala.null':       ('magenta', 'default'),

        'scala.integer':  ('default', 'default'),
        'scala.float':    ('default', 'default'),
        'scala.bareword': ('default', 'default'),

        'scala.class': ('yellow', 'default'),
        'scala.def':   ('blue', 'default'),
    }

    _bindings   = {
        'close-paren':   (')',),
        'close-brace':   ('}',),
        'close-bracket': (']',),
    }

class ScalaPipe(Pipe):
    name    = 'scalapipe'
    grammar = ScalaGrammar

def install(*args):
    Scala.install(*args)
    ScalaPipe.install(*args)