Turn more from cmd_parse.py into exceptions.

Addresses #27 and #103.

core/cmd_exec.py

@@ -203,7 +203,7 @@ def _EvalHelper(self, c_parser, source_name):
      self.arena.PopSource()

  def _Eval(self, argv):
    # TODO: set -o sane-eval should change eval to
    # TODO: set -o sane-eval should change eval to take a single string.
    code_str = ' '.join(argv)
    line_reader = reader.StringLineReader(code_str, self.arena)
    _, c_parser = parse_lib.MakeParser(line_reader, self.arena)

osh/cmd_parse.py

@@ -77,15 +77,6 @@ def ResetInputObjects(self):
  def Error(self):
    return self.error_stack

  def _BadWord(self, msg, w):
    """Helper function for errors involving a word.

    Args:
      msg: format string with a single %s token
      w: Word
    """
    self.AddErrorContext(msg, w, word=w)

  def AddErrorContext(self, msg, *args, **kwargs):
    err = util.ParseError(msg, *args, **kwargs)
    self.error_stack.append(err)
@@ -108,8 +99,8 @@ def _MaybeReadHereDocs(self):
          # fatal because we want to be strict, and because it causes problems
          # reporting other errors.
          # Attribute it to the << in <<EOF for now.
          self.AddErrorContext('Unterminated here doc', span_id=h.spids[0])
          return False
          p_die("Couldn't find terminator for here doc that starts here",
                span_id=h.spids[0])

        # NOTE: Could do this runtime to preserve LST.
        if h.op_id == Id.Redir_DLessDash:
@@ -252,8 +243,7 @@ def ParseRedirect(self):
      # NOTE: \EOF counts, or even E\OF
      ok, node.here_end, quoted = word.StaticEval(self.cur_word)
      if not ok:
        self._BadWord('Error evaluating here doc delimiter: %s', self.cur_word)
        return None
        p_die('Invalid here doc delimiter', word=self.cur_word)
      node.do_expansion = not quoted
      self._Next()

@@ -352,9 +342,7 @@ def _MakeSimpleCommand(self, prefix_bindings, suffix_words, redirects):
    # FOO=(1 2 3) ls is not allowed
    for k, _, v, _ in prefix_bindings:
      if word.HasArrayPart(v):
        self.AddErrorContext(
            'Unexpected array literal in binding: %s', v, word=v)
        return None
        p_die("Environment bindings can't contain array literals", word=v)

    # echo FOO=(1 2 3) is not allowed
    # NOTE: Other checks can be inserted here.  Can resolve builtins,
@@ -364,8 +352,7 @@ def _MakeSimpleCommand(self, prefix_bindings, suffix_words, redirects):
      if kov:
        _, _, v = kov
        if word.HasArrayPart(v):
          self.AddErrorContext('Unexpected array literal: %s', v, word=w)
          return None
          p_die("Commands can't contain array literals", word=w)

    # NOTE: # In bash, {~bob,~jane}/src works, even though ~ isn't the leading
    # character of the initial word.
@@ -382,9 +369,7 @@ def _MakeSimpleCommand(self, prefix_bindings, suffix_words, redirects):
    for name, op, val, left_spid in prefix_bindings:
      if op != assign_op_e.Equal:
        # NOTE: Using spid of RHS for now, since we don't have one for op.
        self.AddErrorContext('Expected = in environment binding, got +=',
            word=val)
        return None
        p_die('Expected = in environment binding, got +=', word=val)
      pair = ast.env_pair(name, val)
      pair.spids.append(left_spid)
      node.more_env.append(pair)

osh/cmd_parse_test.py

@@ -31,7 +31,10 @@ def InitCommandParser(code_str):
def _assertParseMethod(test, code_str, method, expect_success=True):
  arena, c_parser = InitCommandParser(code_str)
  m = getattr(c_parser, method)
  node = m()
  try:
    node = m()
  except util.ParseError as e:
    node = None

  if node:
    ast_lib.PrettyPrint(node)

test/parse-errors.sh

@@ -196,10 +196,20 @@ cmd-parse() {
  _error-case 'echo $( echo > >>  )'
}

simple-command() {
  set +o errexit

  _error-case 'PYTHONPATH=. FOO=(1 2) python'
  _error-case 'echo foo FOO=(1 2)'

  _error-case 'PYTHONPATH+=1 python'
}

cases-in-strings() {
  set +o errexit

  cmd-parse
  simple-command

  # Word
  word-parse