# Copyright 2013-2024 Lawrence Livermore National Security, LLC and other
# Spack Project Developers. See the top-level COPYRIGHT file for details.
#
# SPDX-License-Identifier: (Apache-2.0 OR MIT)
import itertools
import textwrap
from typing import List, Optional, Tuple
import llnl.util.lang
import spack.config
import spack.extensions
from spack.util.path import canonicalize_path
[docs]
class ContextMeta(type):
"""Meta class for Context. It helps reducing the boilerplate in
client code.
"""
#: Keeps track of the context properties that have been added
#: by the class that is being defined
_new_context_properties: List[str] = []
def __new__(cls, name, bases, attr_dict):
# Merge all the context properties that are coming from base classes
# into a list without duplicates.
context_properties = list(cls._new_context_properties)
for x in bases:
try:
context_properties.extend(x.context_properties)
except AttributeError:
pass
context_properties = list(llnl.util.lang.dedupe(context_properties))
# Flush the list
cls._new_context_properties = []
# Attach the list to the class being created
attr_dict["context_properties"] = context_properties
return super(ContextMeta, cls).__new__(cls, name, bases, attr_dict)
[docs]
@classmethod
def context_property(cls, func):
"""Decorator that adds a function name to the list of new context
properties, and then returns a property.
"""
name = func.__name__
cls._new_context_properties.append(name)
return property(func)
#: A saner way to use the decorator
context_property = ContextMeta.context_property
[docs]
class Context(metaclass=ContextMeta):
"""Base class for context classes that are used with the template
engine.
"""
[docs]
def to_dict(self):
"""Returns a dictionary containing all the context properties."""
d = [(name, getattr(self, name)) for name in self.context_properties]
return dict(d)
[docs]
@llnl.util.lang.memoized
def make_environment(dirs: Optional[Tuple[str, ...]] = None):
"""Returns a configured environment for template rendering."""
# Import at this scope to avoid slowing Spack startup down
import jinja2
if dirs is None:
# Default directories where to search for templates
builtins = spack.config.get("config:template_dirs", ["$spack/share/spack/templates"])
extensions = spack.extensions.get_template_dirs()
dirs = tuple(canonicalize_path(d) for d in itertools.chain(builtins, extensions))
# Loader for the templates
loader = jinja2.FileSystemLoader(dirs)
# Environment of the template engine
env = jinja2.Environment(loader=loader, trim_blocks=True, lstrip_blocks=True)
# Custom filters
_set_filters(env)
return env
# Extra filters for template engine environment
[docs]
def prepend_to_line(text, token):
"""Prepends a token to each line in text"""
return [token + line for line in text]
[docs]
def quote(text):
"""Quotes each line in text"""
return ['"{0}"'.format(line) for line in text]
[docs]
def curly_quote(text):
"""Encloses each line of text in curly braces"""
return ["{{{0}}}".format(line) for line in text]
def _set_filters(env):
"""Sets custom filters to the template engine environment"""
env.filters["textwrap"] = textwrap.wrap
env.filters["prepend_to_line"] = prepend_to_line
env.filters["join"] = "\n".join
env.filters["quote"] = quote
env.filters["curly_quote"] = curly_quote