Fix some error handling in the interactive loop.

Still have more to do.

bin/oil.py

@@ -95,7 +95,7 @@ def _tlog(msg):
_tlog('after imports')


def InteractiveLoop(opts, ex, c_parser, w_parser, line_reader):
def InteractiveLoop(opts, ex, c_parser, w_parser, line_reader, arena):
  if opts.show_ast:
    ast_f = fmt.DetectConsoleOutput(sys.stdout)
  else:
@@ -113,19 +113,25 @@ def InteractiveLoop(opts, ex, c_parser, w_parser, line_reader):
      raise RuntimeError('Failed parse: %s' % c_parser.Error())
    c_id = word.CommandId(w)
    if c_id == Id.Op_Newline:
      print('nothing to execute')
      #print('nothing to execute')
      pass
    elif c_id == Id.Eof_Real:
      print('EOF')
      break
    else:
      node = c_parser.ParseCommandLine()

      # Failed parse.
      # TODO: Need an error for an empty command, which we ignore?  GetLine
      # could do that in the first position?
      # ParseSimpleCommand fails with '\n' token?
      if not node:
        # TODO: PrintError here
        raise RuntimeError('failed parse: %s' % c_parser.Error())
        e = c_parser.Error()
        # NOTE: This is a bit verbose.
        ui.PrintErrorStack(e, arena, sys.stderr)
        w_parser.Reset()
        c_parser.Reset()
        continue

      if ast_f:
        ast_lib.PrettyPrint(node)
@@ -305,14 +311,18 @@ def OshMain(argv0, argv, login_shell):
      completion.Init(pool, builtin.BUILTIN_DEF, mem, funcs, comp_lookup,
                      status_out, ev)

    return InteractiveLoop(opts, ex, c_parser, w_parser, line_reader)
    return InteractiveLoop(opts, ex, c_parser, w_parser, line_reader, arena)
  else:
    # Parse the whole thing up front
    #print('Parsing file')

    _tlog('ParseWholeFile')
    # TODO: Do I need ParseAndEvalLoop?  How is it different than
    # InteractiveLoop?

    # TODO: InteractiveLoop above should use the same form of error handling.
    # ParseWholeFile vs. ParseCommandLine
    # I think ParseCommandLine should just be a loop
    try:
      node = c_parser.ParseWholeFile()
    except util.ParseError as e:

core/process.py

@@ -312,15 +312,25 @@ def Run(self):


def ExecExternalProgram(argv, environ):
  """
  """Execute a program and exit this process.

  Called by:
  ls /
  exec ls /
  ( ls / )
  """
  # TODO: If there is an error, like the file isn't executable, then we should
  # exit, and the parent will reap it.  Should it capture stderr?
  try:
    os.execvpe(argv[0], argv, environ)
  except OSError as e:
    log('Unexpected error in execvpe(%r, %r, ...): %s', argv[0], argv, e)
    # Command not found means 127.  TODO: Are there other cases?

    # TODO:
    # - Make this error look better.
    # - What about permission errors?

    # Command not found means 127.
    sys.exit(127)
  # no return

osh/cmd_parse.py

@@ -1537,6 +1537,9 @@ def ParseWholeFile(self):

    TODO: This should be turned into a Parse and Execute loop, freeing arenas
    if they don't contain functions.

    osh -n is a different loop -- it parses each line one at a time, but
    doesn't execute!
    """
    if not self._NewlineOk(): return None