mirror of
https://github.com/evennia/evennia.git
synced 2026-04-03 06:27:17 +02:00
349 lines
12 KiB
Python
349 lines
12 KiB
Python
"""
|
|
Inline functions (nested form).
|
|
|
|
This parser accepts nested inlinefunctions on the form
|
|
|
|
```
|
|
$funcname(arg, arg, ...)
|
|
```
|
|
|
|
embedded in any text where any arg can be another $funcname{} call.
|
|
This functionality is turned off by default - to activate,
|
|
`settings.INLINEFUNC_ENABLED` must be set to `True`.
|
|
|
|
Each token starts with "$funcname(" where there must be no space
|
|
between the $funcname and (. It ends with a matched ending parentesis.
|
|
")".
|
|
|
|
Inside the inlinefunc definition, one can use `\` to escape. This is
|
|
mainly needed for escaping commas in flowing text (which would
|
|
otherwise be interpreted as an argument separator), or to escape `}`
|
|
when not intended to close the function block. Enclosing text in
|
|
matched `\"\"\"` (triple quotes) or `'''` (triple single-quotes) will
|
|
also escape *everything* within without needing to escape individual
|
|
characters.
|
|
|
|
The available inlinefuncs are defined as global-level functions in
|
|
modules defined by `settings.INLINEFUNC_MODULES`. They are identified
|
|
by their function name (and ignored if this name starts with `_`). They
|
|
should be on the following form:
|
|
|
|
```python
|
|
def funcname (*args, **kwargs):
|
|
# ...
|
|
```
|
|
|
|
Here, the arguments given to `$funcname(arg1,arg2)` will appear as the
|
|
`*args` tuple. This will be populated by the arguments given to the
|
|
inlinefunc in-game - the only part that will be available from
|
|
in-game. `**kwargs` are not supported from in-game but are only used
|
|
internally by Evennia to make details about the caller available to
|
|
the function. The kwarg passed to all functions is `session`, the
|
|
Sessionobject for the object seeing the string. This may be `None` if
|
|
the string is sent to a non-puppetable object. The inlinefunc should
|
|
never raise an exception.
|
|
|
|
There are two reserved function names:
|
|
- "nomatch": This is called if the user uses a functionname that is
|
|
not registered. The nomatch function will get the name of the
|
|
not-found function as its first argument followed by the normal
|
|
arguments to the given function. If not defined the default effect is
|
|
to print `<UNKNOWN>` to replace the unknown function.
|
|
- "stackfull": This is called when the maximum nested function stack is reached.
|
|
When this happens, the original parsed string is returned and the result of
|
|
the `stackfull` inlinefunc is appended to the end. By default this is an
|
|
error message.
|
|
|
|
Error handling:
|
|
Syntax errors, notably not completely closing all inlinefunc
|
|
blocks, will lead to the entire string remaining unparsed.
|
|
|
|
"""
|
|
|
|
import re
|
|
from django.conf import settings
|
|
from evennia.utils import utils
|
|
|
|
|
|
# example/testing inline functions
|
|
|
|
def pad(*args, **kwargs):
|
|
"""
|
|
Inlinefunc. Pads text to given width.
|
|
|
|
Args:
|
|
text (str, optional): Text to pad.
|
|
width (str, optional): Will be converted to integer. Width
|
|
of padding.
|
|
align (str, optional): Alignment of padding; one of 'c', 'l' or 'r'.
|
|
fillchar (str, optional): Character used for padding. Defaults to a space.
|
|
|
|
Kwargs:
|
|
session (Session): Session performing the pad.
|
|
|
|
Example:
|
|
`$pad(text, width, align, fillchar)`
|
|
|
|
"""
|
|
text, width, align, fillchar = "", 78, 'c', ' '
|
|
nargs = len(args)
|
|
if nargs > 0:
|
|
text = args[0]
|
|
if nargs > 1:
|
|
width = int(args[1]) if args[1].strip().isdigit() else 78
|
|
if nargs > 2:
|
|
align = args[2] if args[2] in ('c', 'l', 'r') else 'c'
|
|
if nargs > 3:
|
|
fillchar = args[3]
|
|
return utils.pad(text, width=width, align=align, fillchar=fillchar)
|
|
|
|
|
|
def crop(*args, **kwargs):
|
|
"""
|
|
Inlinefunc. Crops ingoing text to given widths.
|
|
|
|
Args:
|
|
text (str, optional): Text to crop.
|
|
width (str, optional): Will be converted to an integer. Width of
|
|
crop in characters.
|
|
suffix (str, optional): End string to mark the fact that a part
|
|
of the string was cropped. Defaults to `[...]`.
|
|
Kwargs:
|
|
session (Session): Session performing the crop.
|
|
|
|
Example:
|
|
`$crop(text, width=78, suffix='[...]')`
|
|
|
|
"""
|
|
text, width, suffix = "", 78, "[...]"
|
|
nargs = len(args)
|
|
if nargs > 0:
|
|
text = args[0]
|
|
if nargs > 1:
|
|
width = int(args[1]) if args[1].strip().isdigit() else 78
|
|
if nargs > 2:
|
|
suffix = args[2]
|
|
return utils.crop(text, width=width, suffix=suffix)
|
|
|
|
|
|
def clr(*args, **kwargs):
|
|
"""
|
|
Inlinefunc. Colorizes nested text.
|
|
|
|
Args:
|
|
startclr (str, optional): An ANSI color abbreviation without the
|
|
prefix `|`, such as `r` (red foreground) or `[r` (red background).
|
|
text (str, optional): Text
|
|
endclr (str, optional): The color to use at the end of the string. Defaults
|
|
to `|n` (reset-color).
|
|
Kwargs:
|
|
session (Session): Session object triggering inlinefunc.
|
|
|
|
Example:
|
|
`$clr(startclr, text, endclr)`
|
|
|
|
"""
|
|
text = ""
|
|
nargs = len(args)
|
|
if nargs > 0:
|
|
color = args[0].strip()
|
|
if nargs > 1:
|
|
text = args[1]
|
|
text = "|" + color + text
|
|
if nargs > 2:
|
|
text += "|" + args[2].strip()
|
|
else:
|
|
text += "|n"
|
|
return text
|
|
|
|
|
|
# we specify a default nomatch function to use if no matching func was
|
|
# found. This will be overloaded by any nomatch function defined in
|
|
# the imported modules.
|
|
_INLINE_FUNCS = {"nomatch": lambda *args, **kwargs: "<UKNOWN>",
|
|
"stackfull": lambda *args, **kwargs: "\n (not parsed: inlinefunc stack size exceeded.)"}
|
|
|
|
|
|
# load custom inline func modules.
|
|
for module in utils.make_iter(settings.INLINEFUNC_MODULES):
|
|
_INLINE_FUNCS.update(utils.all_from_module(module))
|
|
|
|
# remove the core function if we include examples in this module itself
|
|
#_INLINE_FUNCS.pop("inline_func_parse", None)
|
|
|
|
|
|
# The stack size is a security measure. Set to <=0 to disable.
|
|
try:
|
|
_STACK_MAXSIZE = settings.INLINEFUNC_STACK_MAXSIZE
|
|
except AttributeError:
|
|
_STACK_MAXSIZE = 20
|
|
|
|
# regex definitions
|
|
|
|
_RE_STARTTOKEN = re.compile(r"(?<!\\)\$(\w+)\(") # unescaped $funcname{ (start of function call)
|
|
|
|
_RE_TOKEN = re.compile(r"""
|
|
(?<!\\)\'\'\'(?P<singlequote>.*?)(?<!\\)\'\'\'| # unescaped single-triples (escapes all inside them)
|
|
(?<!\\)\"\"\"(?P<doublequote>.*?)(?<!\\)\"\"\"| # unescaped normal triple quotes (escapes all inside them)
|
|
(?P<comma>(?<!\\)\,)| # unescaped , (argument separator)
|
|
(?P<end>(?<!\\)\))| # unescaped } (end of function call)
|
|
(?P<start>(?<!\\)\$\w+\()| # unescaped $funcname{ (start of function call)
|
|
(?P<escaped>\\'|\\"|\\\)|\\$\w+\()| # escaped tokens should re-appear in text
|
|
(?P<rest>[\w\s.-\/#!%\^&\*;:=\-_`~\(}{\[\]]+) # everything else should also be included""",
|
|
re.UNICODE + re.IGNORECASE + re.VERBOSE + re.DOTALL)
|
|
|
|
|
|
# Cache for function lookups.
|
|
_PARSING_CACHE = utils.LimitedSizeOrderedDict(size_limit=1000)
|
|
|
|
class ParseStack(list):
|
|
"""
|
|
Custom stack that always concatenates strings together when the
|
|
strings are added next to one another. Tuples are stored
|
|
separately and None is used to mark that a string should be broken
|
|
up into a new chunk. Below is the resulting stack after separately
|
|
appending 3 strings, None, 2 strings, a tuple and finally 2
|
|
strings:
|
|
|
|
[string + string + string,
|
|
None
|
|
string + string,
|
|
tuple,
|
|
string + string]
|
|
|
|
"""
|
|
def __init__(self, *args, **kwargs):
|
|
super(ParseStack, self).__init__(*args, **kwargs)
|
|
# always start stack with the empty string
|
|
list.append(self, "")
|
|
# indicates if the top of the stack is a string or not
|
|
self._string_last = True
|
|
|
|
def append(self, item):
|
|
"""
|
|
The stack will merge strings, add other things as normal
|
|
"""
|
|
if isinstance(item, basestring):
|
|
if self._string_last:
|
|
self[-1] += item
|
|
else:
|
|
list.append(self, item)
|
|
self._string_last = True
|
|
else:
|
|
# everything else is added as normal
|
|
list.append(self, item)
|
|
self._string_last = False
|
|
|
|
|
|
class InlinefuncError(RuntimeError):
|
|
pass
|
|
|
|
def parse_inlinefunc(string, strip=False, **kwargs):
|
|
"""
|
|
Parse the incoming string.
|
|
|
|
Args:
|
|
string (str): The incoming string to parse.
|
|
strip (bool, optional): Whether to strip function calls rather than
|
|
execute them.
|
|
Kwargs:
|
|
session (Session): This is sent to this function by Evennia when triggering
|
|
it. It is passed to the inlinefunc.
|
|
kwargs (any): All other kwargs are also passed on to the inlinefunc.
|
|
|
|
|
|
"""
|
|
global _PARSING_CACHE
|
|
if string in _PARSING_CACHE:
|
|
# stack is already cached
|
|
stack = _PARSING_CACHE[string]
|
|
else:
|
|
# not a cached string.
|
|
if not _RE_STARTTOKEN.search(string):
|
|
# if there are no unescaped start tokens at all, return immediately.
|
|
return string
|
|
|
|
# build a new cache entry
|
|
stack = ParseStack()
|
|
ncallable = 0
|
|
for match in _RE_TOKEN.finditer(string):
|
|
gdict = match.groupdict()
|
|
if gdict["singlequote"]:
|
|
stack.append(gdict["singlequote"])
|
|
elif gdict["doublequote"]:
|
|
stack.append(gdict["doublequote"])
|
|
elif gdict["end"]:
|
|
if ncallable <= 0:
|
|
stack.append(")")
|
|
continue
|
|
args = []
|
|
while stack:
|
|
operation = stack.pop()
|
|
if callable(operation):
|
|
if not strip:
|
|
stack.append((operation, [arg for arg in reversed(args)]))
|
|
ncallable -= 1
|
|
break
|
|
else:
|
|
args.append(operation)
|
|
elif gdict["start"]:
|
|
funcname = _RE_STARTTOKEN.match(gdict["start"]).group(1)
|
|
try:
|
|
# try to fetch the matching inlinefunc from storage
|
|
stack.append(_INLINE_FUNCS[funcname])
|
|
except KeyError:
|
|
stack.append(_INLINE_FUNCS["nomatch"])
|
|
stack.append(funcname)
|
|
ncallable += 1
|
|
elif gdict["escaped"]:
|
|
# escaped tokens
|
|
token = gdict["escaped"].lstrip("\\")
|
|
stack.append(token)
|
|
elif gdict["comma"]:
|
|
if ncallable > 0:
|
|
# commas outside strings and inside a callable are
|
|
# used to mark argument separation - we use None
|
|
# in the stack to indicate such a separation.
|
|
stack.append(None)
|
|
else:
|
|
# no callable active - just a string
|
|
stack.append(",")
|
|
else:
|
|
# the rest
|
|
stack.append(gdict["rest"])
|
|
|
|
if ncallable > 0:
|
|
# this means not all inlinefuncs were complete
|
|
return string
|
|
|
|
if _STACK_MAXSIZE > 0 and _STACK_MAXSIZE < len(stack):
|
|
# if stack is larger than limit, throw away parsing
|
|
return string + gdict["stackfull"](*args, **kwargs)
|
|
else:
|
|
# cache the result
|
|
_PARSING_CACHE[string] = stack
|
|
|
|
# run the stack recursively
|
|
def _run_stack(item, depth=0):
|
|
retval = item
|
|
if isinstance(item, tuple):
|
|
if strip:
|
|
return ""
|
|
else:
|
|
func, arglist = item
|
|
args = [""]
|
|
for arg in arglist:
|
|
if arg is None:
|
|
# an argument-separating comma - start a new arg
|
|
args.append("")
|
|
else:
|
|
# all other args should merge into one string
|
|
args[-1] += _run_stack(arg, depth=depth+1)
|
|
# execute the inlinefunc at this point or strip it.
|
|
kwargs["inlinefunc_stack_depth"] = depth
|
|
retval = "" if strip else func(*args, **kwargs)
|
|
return utils.to_str(retval, force_string=True)
|
|
|
|
# execute the stack from the cache
|
|
return "".join(_run_stack(item) for item in _PARSING_CACHE[string])
|
|
|