diff options
Diffstat (limited to 'cmd2/parsing.py')
| -rw-r--r-- | cmd2/parsing.py | 95 |
1 files changed, 77 insertions, 18 deletions
diff --git a/cmd2/parsing.py b/cmd2/parsing.py index 8edfacb9..e90eac43 100644 --- a/cmd2/parsing.py +++ b/cmd2/parsing.py @@ -14,6 +14,55 @@ from . import utils @attr.s(frozen=True) +class MacroArg: + """ + Information used to replace or unescape arguments in a macro value when the macro is resolved + Normal argument syntax : {5} + Escaped argument syntax: {{5}} + """ + # The starting index of this argument in the macro value + start_index = attr.ib(validator=attr.validators.instance_of(int)) + + # The number string that appears between the braces + # This is a string instead of an int because we support unicode digits and must be able + # to reproduce this string later + number_str = attr.ib(validator=attr.validators.instance_of(str)) + + # Tells if this argument is escaped and therefore needs to be unescaped + is_escaped = attr.ib(validator=attr.validators.instance_of(bool)) + + # Pattern used to find normal argument + # Digits surrounded by exactly 1 brace on a side and 1 or more braces on the opposite side + # Match strings like: {5}, {{{{{4}, {2}}}}} + macro_normal_arg_pattern = re.compile(r'(?<!{){\d+}|{\d+}(?!})') + + # Pattern used to find escaped arguments + # Digits surrounded by 2 or more braces on both sides + # Match strings like: {{5}}, {{{{{4}}, {{2}}}}} + macro_escaped_arg_pattern = re.compile(r'{{2}\d+}{2}') + + # Finds a string of digits + digit_pattern = re.compile(r'\d+') + + +@attr.s(frozen=True) +class Macro: + """Defines a cmd2 macro""" + + # Name of the macro + name = attr.ib(validator=attr.validators.instance_of(str)) + + # The string the macro resolves to + value = attr.ib(validator=attr.validators.instance_of(str)) + + # The required number of args the user has to pass to this macro + required_arg_count = attr.ib(validator=attr.validators.instance_of(int)) + + # Used to fill in argument placeholders in the macro + arg_list = attr.ib(default=attr.Factory(list), validator=attr.validators.instance_of(list)) + + +@attr.s(frozen=True) class Statement(str): """String subclass with additional attributes to store the results of parsing. @@ -81,34 +130,34 @@ class Statement(str): argv[1:], which strips them all off for you. """ # the arguments, but not the command, nor the output redirection clauses. - args = attr.ib(default='', validator=attr.validators.instance_of(str), type=str) + args = attr.ib(default='', validator=attr.validators.instance_of(str)) # string containing exactly what we input by the user - raw = attr.ib(default='', validator=attr.validators.instance_of(str), type=str) + raw = attr.ib(default='', validator=attr.validators.instance_of(str)) # the command, i.e. the first whitespace delimited word - command = attr.ib(default='', validator=attr.validators.instance_of(str), type=str) + command = attr.ib(default='', validator=attr.validators.instance_of(str)) # list of arguments to the command, not including any output redirection or terminators; quoted args remain quoted - arg_list = attr.ib(factory=list, validator=attr.validators.instance_of(list), type=List[str]) + arg_list = attr.ib(default=attr.Factory(list), validator=attr.validators.instance_of(list)) # if the command is a multiline command, the name of the command, otherwise empty - multiline_command = attr.ib(default='', validator=attr.validators.instance_of(str), type=str) + multiline_command = attr.ib(default='', validator=attr.validators.instance_of(str)) # the character which terminated the multiline command, if there was one - terminator = attr.ib(default='', validator=attr.validators.instance_of(str), type=str) + terminator = attr.ib(default='', validator=attr.validators.instance_of(str)) # characters appearing after the terminator but before output redirection, if any - suffix = attr.ib(default='', validator=attr.validators.instance_of(str), type=str) + suffix = attr.ib(default='', validator=attr.validators.instance_of(str)) # if output was piped to a shell command, the shell command as a list of tokens - pipe_to = attr.ib(factory=list, validator=attr.validators.instance_of(list), type=List[str]) + pipe_to = attr.ib(default=attr.Factory(list), validator=attr.validators.instance_of(list)) # if output was redirected, the redirection token, i.e. '>>' - output = attr.ib(default='', validator=attr.validators.instance_of(str), type=str) + output = attr.ib(default='', validator=attr.validators.instance_of(str)) # if output was redirected, the destination file - output_to = attr.ib(default='', validator=attr.validators.instance_of(str), type=str) + output_to = attr.ib(default='', validator=attr.validators.instance_of(str)) def __new__(cls, value: object, *pos_args, **kw_args): """Create a new instance of Statement. @@ -247,23 +296,33 @@ class StatementParser: self._command_pattern = re.compile(expr) def is_valid_command(self, word: str) -> Tuple[bool, str]: - """Determine whether a word is a valid alias. + """Determine whether a word is a valid name for a command. - Aliases can not include redirection characters, whitespace, - or termination characters. + Commands can not include redirection characters, whitespace, + or termination characters. They also cannot start with a + shortcut. - If word is not a valid command, return False and a comma - separated string of characters that can not appear in a command. + If word is not a valid command, return False and error text This string is suitable for inclusion in an error message of your choice: - valid, invalidchars = statement_parser.is_valid_command('>') + valid, errmsg = statement_parser.is_valid_command('>') if not valid: - errmsg = "Aliases can not contain: {}".format(invalidchars) + errmsg = "Alias {}".format(errmsg) """ valid = False - errmsg = 'whitespace, quotes, ' + if not word: + return False, 'cannot be an empty string' + + for (shortcut, _) in self.shortcuts: + if word.startswith(shortcut): + # Build an error string with all shortcuts listed + errmsg = 'cannot start with a shortcut: ' + errmsg += ', '.join(shortcut for (shortcut, _) in self.shortcuts) + return False, errmsg + + errmsg = 'cannot contain: whitespace, quotes, ' errchars = [] errchars.extend(constants.REDIRECTION_CHARS) errchars.extend(self.terminators) |