Completed
Push — extra-context-cli ( af51e0...e7614b )
by Michael
01:02
created

cookiecutter.StrictEnvironment.__init__()   A

Complexity

Conditions 1

Size

Total Lines 4

Duplication

Lines 0
Ratio 0 %
Metric Value
cc 1
dl 0
loc 4
rs 10
1
# -*- coding: utf-8 -*-
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from jinja2 import Environment, StrictUndefined
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from .exceptions import UnknownExtension
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class ExtensionLoaderMixin(object):
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    """Mixin that provides a sane way of loading extensions specified in a
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    given context.
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    The context is being extracted from the keyword arguments before calling
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    the next parent class in line of the child.
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    """
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    def __init__(self, **kwargs):
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        context = kwargs.pop('context', {})
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        default_extensions = [
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            'jinja2_time.TimeExtension',
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        ]
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        extensions = default_extensions + self._read_extensions(context)
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        try:
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            super(ExtensionLoaderMixin, self).__init__(
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                extensions=extensions,
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                **kwargs
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            )
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        except ImportError as err:
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            raise UnknownExtension('Unable to load extension: {}'.format(err))
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    def _read_extensions(self, context):
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        """Return a list of extensions as str to be passed on to the jinja2
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        env. If context does not contain the relevant info, return an empty
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        list instead.
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        """
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        try:
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            extensions = context['cookiecutter']['_extensions']
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        except KeyError:
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            return []
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        else:
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            return [str(ext) for ext in extensions]
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class StrictEnvironment(ExtensionLoaderMixin, Environment):
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    """Jinja2 environment that raises an error when it hits a variable
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    which is not defined in the context used to render a template.
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    """
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    def __init__(self, **kwargs):
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        super(StrictEnvironment, self).__init__(
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            undefined=StrictUndefined,
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            **kwargs
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        )
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