Implement BASH_REMATCH with the libc.regex_match() function.

Fixes #133.

core/expr_eval.py

@@ -17,10 +17,10 @@
except ImportError:
  from benchmarks import fake_libc as libc

from osh.meta import BOOL_ARG_TYPES, Id, types
from core import util
from core import state
from osh.meta import BOOL_ARG_TYPES, Id, types
from osh.meta import runtime

from osh.meta import ast

log = util.log
@@ -444,7 +444,7 @@ class BoolEvaluator(_ExprEvaluator):

  def _SetRegexMatches(self, matches):
    """For ~= to set the BASH_REMATCH array."""
    self.mem
    state.SetGlobalArray(self.mem, 'BASH_REMATCH', matches)

  def _EvalCompoundWord(self, word, do_fnmatch=False):
    """
@@ -606,22 +606,19 @@ def Eval(self, node):
          return s1 != s2

        if op_id == Id.BoolBinary_EqualTilde:
          # NOTE: regex matching can't fail if compilation succeeds.
          match = libc.regex_match(s2, s1)
          # TODO: BASH_REMATCH or REGEX_MATCH
          if match == 1:
            self._SetRegexMatches('TODO')
            is_match = True
          elif match == 0:
            is_match = False
          elif match == -1:
          matches = libc.regex_match(s2, s1)

          # NOTE: regex matching shouldn't fail if compilation succeeds.
          if matches == -1:
            raise AssertionError(
                "Invalid regex %r: should have been caught at compile time" %
                s2)
          else:
            raise AssertionError

          return is_match
          if matches is None:
            return False

          self._SetRegexMatches(matches)
          return True

        if op_id == Id.Redir_Less:  # pun
          return s1 < s2

spec/regex.test.sh

@@ -34,6 +34,16 @@
# From bash code: ( | ) are treated special.  Normally they must be quoted, but
# they can be UNQUOTED in BASH_REGEX state.  In fact they can't be quoted!

### BASH_REMATCH
[[ foo123 =~ ([a-z]+)([0-9]+) ]]
argv.py "${BASH_REMATCH[@]}"
## STDOUT:
['foo123', 'foo', '123']
## END
## N-I zsh STDOUT:
['']
## END

### Match is unanchored at both ends
[[ 'bar' =~ a ]] && echo true
# stdout: true