Clone of chromium aad1ce808763f59c7a3753e08f1500a104ecc6fd refs/remotes/origin/HEAD
diff --git a/third_party/jinja2/environment.py b/third_party/jinja2/environment.py
new file mode 100644
index 0000000..45fabad
--- /dev/null
+++ b/third_party/jinja2/environment.py
@@ -0,0 +1,1191 @@
+# -*- coding: utf-8 -*-
+"""
+ jinja2.environment
+ ~~~~~~~~~~~~~~~~~~
+
+ Provides a class that holds runtime and parsing time options.
+
+ :copyright: (c) 2010 by the Jinja Team.
+ :license: BSD, see LICENSE for more details.
+"""
+import os
+import sys
+from jinja2 import nodes
+from jinja2.defaults import BLOCK_START_STRING, \
+ BLOCK_END_STRING, VARIABLE_START_STRING, VARIABLE_END_STRING, \
+ COMMENT_START_STRING, COMMENT_END_STRING, LINE_STATEMENT_PREFIX, \
+ LINE_COMMENT_PREFIX, TRIM_BLOCKS, NEWLINE_SEQUENCE, \
+ DEFAULT_FILTERS, DEFAULT_TESTS, DEFAULT_NAMESPACE, \
+ KEEP_TRAILING_NEWLINE, LSTRIP_BLOCKS
+from jinja2.lexer import get_lexer, TokenStream
+from jinja2.parser import Parser
+from jinja2.nodes import EvalContext
+from jinja2.optimizer import optimize
+from jinja2.compiler import generate
+from jinja2.runtime import Undefined, new_context
+from jinja2.exceptions import TemplateSyntaxError, TemplateNotFound, \
+ TemplatesNotFound, TemplateRuntimeError
+from jinja2.utils import import_string, LRUCache, Markup, missing, \
+ concat, consume, internalcode
+from jinja2._compat import imap, ifilter, string_types, iteritems, \
+ text_type, reraise, implements_iterator, implements_to_string, \
+ get_next, encode_filename, PY2, PYPY
+from functools import reduce
+
+
+# for direct template usage we have up to ten living environments
+_spontaneous_environments = LRUCache(10)
+
+# the function to create jinja traceback objects. This is dynamically
+# imported on the first exception in the exception handler.
+_make_traceback = None
+
+
+def get_spontaneous_environment(*args):
+ """Return a new spontaneous environment. A spontaneous environment is an
+ unnamed and unaccessible (in theory) environment that is used for
+ templates generated from a string and not from the file system.
+ """
+ try:
+ env = _spontaneous_environments.get(args)
+ except TypeError:
+ return Environment(*args)
+ if env is not None:
+ return env
+ _spontaneous_environments[args] = env = Environment(*args)
+ env.shared = True
+ return env
+
+
+def create_cache(size):
+ """Return the cache class for the given size."""
+ if size == 0:
+ return None
+ if size < 0:
+ return {}
+ return LRUCache(size)
+
+
+def copy_cache(cache):
+ """Create an empty copy of the given cache."""
+ if cache is None:
+ return None
+ elif type(cache) is dict:
+ return {}
+ return LRUCache(cache.capacity)
+
+
+def load_extensions(environment, extensions):
+ """Load the extensions from the list and bind it to the environment.
+ Returns a dict of instantiated environments.
+ """
+ result = {}
+ for extension in extensions:
+ if isinstance(extension, string_types):
+ extension = import_string(extension)
+ result[extension.identifier] = extension(environment)
+ return result
+
+
+def _environment_sanity_check(environment):
+ """Perform a sanity check on the environment."""
+ assert issubclass(environment.undefined, Undefined), 'undefined must ' \
+ 'be a subclass of undefined because filters depend on it.'
+ assert environment.block_start_string != \
+ environment.variable_start_string != \
+ environment.comment_start_string, 'block, variable and comment ' \
+ 'start strings must be different'
+ assert environment.newline_sequence in ('\r', '\r\n', '\n'), \
+ 'newline_sequence set to unknown line ending string.'
+ return environment
+
+
+class Environment(object):
+ r"""The core component of Jinja is the `Environment`. It contains
+ important shared variables like configuration, filters, tests,
+ globals and others. Instances of this class may be modified if
+ they are not shared and if no template was loaded so far.
+ Modifications on environments after the first template was loaded
+ will lead to surprising effects and undefined behavior.
+
+ Here the possible initialization parameters:
+
+ `block_start_string`
+ The string marking the begin of a block. Defaults to ``'{%'``.
+
+ `block_end_string`
+ The string marking the end of a block. Defaults to ``'%}'``.
+
+ `variable_start_string`
+ The string marking the begin of a print statement.
+ Defaults to ``'{{'``.
+
+ `variable_end_string`
+ The string marking the end of a print statement. Defaults to
+ ``'}}'``.
+
+ `comment_start_string`
+ The string marking the begin of a comment. Defaults to ``'{#'``.
+
+ `comment_end_string`
+ The string marking the end of a comment. Defaults to ``'#}'``.
+
+ `line_statement_prefix`
+ If given and a string, this will be used as prefix for line based
+ statements. See also :ref:`line-statements`.
+
+ `line_comment_prefix`
+ If given and a string, this will be used as prefix for line based
+ based comments. See also :ref:`line-statements`.
+
+ .. versionadded:: 2.2
+
+ `trim_blocks`
+ If this is set to ``True`` the first newline after a block is
+ removed (block, not variable tag!). Defaults to `False`.
+
+ `lstrip_blocks`
+ If this is set to ``True`` leading spaces and tabs are stripped
+ from the start of a line to a block. Defaults to `False`.
+
+ `newline_sequence`
+ The sequence that starts a newline. Must be one of ``'\r'``,
+ ``'\n'`` or ``'\r\n'``. The default is ``'\n'`` which is a
+ useful default for Linux and OS X systems as well as web
+ applications.
+
+ `keep_trailing_newline`
+ Preserve the trailing newline when rendering templates.
+ The default is ``False``, which causes a single newline,
+ if present, to be stripped from the end of the template.
+
+ .. versionadded:: 2.7
+
+ `extensions`
+ List of Jinja extensions to use. This can either be import paths
+ as strings or extension classes. For more information have a
+ look at :ref:`the extensions documentation <jinja-extensions>`.
+
+ `optimized`
+ should the optimizer be enabled? Default is `True`.
+
+ `undefined`
+ :class:`Undefined` or a subclass of it that is used to represent
+ undefined values in the template.
+
+ `finalize`
+ A callable that can be used to process the result of a variable
+ expression before it is output. For example one can convert
+ `None` implicitly into an empty string here.
+
+ `autoescape`
+ If set to true the XML/HTML autoescaping feature is enabled by
+ default. For more details about auto escaping see
+ :class:`~jinja2.utils.Markup`. As of Jinja 2.4 this can also
+ be a callable that is passed the template name and has to
+ return `True` or `False` depending on autoescape should be
+ enabled by default.
+
+ .. versionchanged:: 2.4
+ `autoescape` can now be a function
+
+ `loader`
+ The template loader for this environment.
+
+ `cache_size`
+ The size of the cache. Per default this is ``50`` which means
+ that if more than 50 templates are loaded the loader will clean
+ out the least recently used template. If the cache size is set to
+ ``0`` templates are recompiled all the time, if the cache size is
+ ``-1`` the cache will not be cleaned.
+
+ `auto_reload`
+ Some loaders load templates from locations where the template
+ sources may change (ie: file system or database). If
+ `auto_reload` is set to `True` (default) every time a template is
+ requested the loader checks if the source changed and if yes, it
+ will reload the template. For higher performance it's possible to
+ disable that.
+
+ `bytecode_cache`
+ If set to a bytecode cache object, this object will provide a
+ cache for the internal Jinja bytecode so that templates don't
+ have to be parsed if they were not changed.
+
+ See :ref:`bytecode-cache` for more information.
+ """
+
+ #: if this environment is sandboxed. Modifying this variable won't make
+ #: the environment sandboxed though. For a real sandboxed environment
+ #: have a look at jinja2.sandbox. This flag alone controls the code
+ #: generation by the compiler.
+ sandboxed = False
+
+ #: True if the environment is just an overlay
+ overlayed = False
+
+ #: the environment this environment is linked to if it is an overlay
+ linked_to = None
+
+ #: shared environments have this set to `True`. A shared environment
+ #: must not be modified
+ shared = False
+
+ #: these are currently EXPERIMENTAL undocumented features.
+ exception_handler = None
+ exception_formatter = None
+
+ def __init__(self,
+ block_start_string=BLOCK_START_STRING,
+ block_end_string=BLOCK_END_STRING,
+ variable_start_string=VARIABLE_START_STRING,
+ variable_end_string=VARIABLE_END_STRING,
+ comment_start_string=COMMENT_START_STRING,
+ comment_end_string=COMMENT_END_STRING,
+ line_statement_prefix=LINE_STATEMENT_PREFIX,
+ line_comment_prefix=LINE_COMMENT_PREFIX,
+ trim_blocks=TRIM_BLOCKS,
+ lstrip_blocks=LSTRIP_BLOCKS,
+ newline_sequence=NEWLINE_SEQUENCE,
+ keep_trailing_newline=KEEP_TRAILING_NEWLINE,
+ extensions=(),
+ optimized=True,
+ undefined=Undefined,
+ finalize=None,
+ autoescape=False,
+ loader=None,
+ cache_size=50,
+ auto_reload=True,
+ bytecode_cache=None):
+ # !!Important notice!!
+ # The constructor accepts quite a few arguments that should be
+ # passed by keyword rather than position. However it's important to
+ # not change the order of arguments because it's used at least
+ # internally in those cases:
+ # - spontaneous environments (i18n extension and Template)
+ # - unittests
+ # If parameter changes are required only add parameters at the end
+ # and don't change the arguments (or the defaults!) of the arguments
+ # existing already.
+
+ # lexer / parser information
+ self.block_start_string = block_start_string
+ self.block_end_string = block_end_string
+ self.variable_start_string = variable_start_string
+ self.variable_end_string = variable_end_string
+ self.comment_start_string = comment_start_string
+ self.comment_end_string = comment_end_string
+ self.line_statement_prefix = line_statement_prefix
+ self.line_comment_prefix = line_comment_prefix
+ self.trim_blocks = trim_blocks
+ self.lstrip_blocks = lstrip_blocks
+ self.newline_sequence = newline_sequence
+ self.keep_trailing_newline = keep_trailing_newline
+
+ # runtime information
+ self.undefined = undefined
+ self.optimized = optimized
+ self.finalize = finalize
+ self.autoescape = autoescape
+
+ # defaults
+ self.filters = DEFAULT_FILTERS.copy()
+ self.tests = DEFAULT_TESTS.copy()
+ self.globals = DEFAULT_NAMESPACE.copy()
+
+ # set the loader provided
+ self.loader = loader
+ self.cache = create_cache(cache_size)
+ self.bytecode_cache = bytecode_cache
+ self.auto_reload = auto_reload
+
+ # load extensions
+ self.extensions = load_extensions(self, extensions)
+
+ _environment_sanity_check(self)
+
+ def add_extension(self, extension):
+ """Adds an extension after the environment was created.
+
+ .. versionadded:: 2.5
+ """
+ self.extensions.update(load_extensions(self, [extension]))
+
+ def extend(self, **attributes):
+ """Add the items to the instance of the environment if they do not exist
+ yet. This is used by :ref:`extensions <writing-extensions>` to register
+ callbacks and configuration values without breaking inheritance.
+ """
+ for key, value in iteritems(attributes):
+ if not hasattr(self, key):
+ setattr(self, key, value)
+
+ def overlay(self, block_start_string=missing, block_end_string=missing,
+ variable_start_string=missing, variable_end_string=missing,
+ comment_start_string=missing, comment_end_string=missing,
+ line_statement_prefix=missing, line_comment_prefix=missing,
+ trim_blocks=missing, lstrip_blocks=missing,
+ extensions=missing, optimized=missing,
+ undefined=missing, finalize=missing, autoescape=missing,
+ loader=missing, cache_size=missing, auto_reload=missing,
+ bytecode_cache=missing):
+ """Create a new overlay environment that shares all the data with the
+ current environment except of cache and the overridden attributes.
+ Extensions cannot be removed for an overlayed environment. An overlayed
+ environment automatically gets all the extensions of the environment it
+ is linked to plus optional extra extensions.
+
+ Creating overlays should happen after the initial environment was set
+ up completely. Not all attributes are truly linked, some are just
+ copied over so modifications on the original environment may not shine
+ through.
+ """
+ args = dict(locals())
+ del args['self'], args['cache_size'], args['extensions']
+
+ rv = object.__new__(self.__class__)
+ rv.__dict__.update(self.__dict__)
+ rv.overlayed = True
+ rv.linked_to = self
+
+ for key, value in iteritems(args):
+ if value is not missing:
+ setattr(rv, key, value)
+
+ if cache_size is not missing:
+ rv.cache = create_cache(cache_size)
+ else:
+ rv.cache = copy_cache(self.cache)
+
+ rv.extensions = {}
+ for key, value in iteritems(self.extensions):
+ rv.extensions[key] = value.bind(rv)
+ if extensions is not missing:
+ rv.extensions.update(load_extensions(rv, extensions))
+
+ return _environment_sanity_check(rv)
+
+ lexer = property(get_lexer, doc="The lexer for this environment.")
+
+ def iter_extensions(self):
+ """Iterates over the extensions by priority."""
+ return iter(sorted(self.extensions.values(),
+ key=lambda x: x.priority))
+
+ def getitem(self, obj, argument):
+ """Get an item or attribute of an object but prefer the item."""
+ try:
+ return obj[argument]
+ except (TypeError, LookupError):
+ if isinstance(argument, string_types):
+ try:
+ attr = str(argument)
+ except Exception:
+ pass
+ else:
+ try:
+ return getattr(obj, attr)
+ except AttributeError:
+ pass
+ return self.undefined(obj=obj, name=argument)
+
+ def getattr(self, obj, attribute):
+ """Get an item or attribute of an object but prefer the attribute.
+ Unlike :meth:`getitem` the attribute *must* be a bytestring.
+ """
+ try:
+ return getattr(obj, attribute)
+ except AttributeError:
+ pass
+ try:
+ return obj[attribute]
+ except (TypeError, LookupError, AttributeError):
+ return self.undefined(obj=obj, name=attribute)
+
+ def call_filter(self, name, value, args=None, kwargs=None,
+ context=None, eval_ctx=None):
+ """Invokes a filter on a value the same way the compiler does it.
+
+ .. versionadded:: 2.7
+ """
+ func = self.filters.get(name)
+ if func is None:
+ raise TemplateRuntimeError('no filter named %r' % name)
+ args = [value] + list(args or ())
+ if getattr(func, 'contextfilter', False):
+ if context is None:
+ raise TemplateRuntimeError('Attempted to invoke context '
+ 'filter without context')
+ args.insert(0, context)
+ elif getattr(func, 'evalcontextfilter', False):
+ if eval_ctx is None:
+ if context is not None:
+ eval_ctx = context.eval_ctx
+ else:
+ eval_ctx = EvalContext(self)
+ args.insert(0, eval_ctx)
+ elif getattr(func, 'environmentfilter', False):
+ args.insert(0, self)
+ return func(*args, **(kwargs or {}))
+
+ def call_test(self, name, value, args=None, kwargs=None):
+ """Invokes a test on a value the same way the compiler does it.
+
+ .. versionadded:: 2.7
+ """
+ func = self.tests.get(name)
+ if func is None:
+ raise TemplateRuntimeError('no test named %r' % name)
+ return func(value, *(args or ()), **(kwargs or {}))
+
+ @internalcode
+ def parse(self, source, name=None, filename=None):
+ """Parse the sourcecode and return the abstract syntax tree. This
+ tree of nodes is used by the compiler to convert the template into
+ executable source- or bytecode. This is useful for debugging or to
+ extract information from templates.
+
+ If you are :ref:`developing Jinja2 extensions <writing-extensions>`
+ this gives you a good overview of the node tree generated.
+ """
+ try:
+ return self._parse(source, name, filename)
+ except TemplateSyntaxError:
+ exc_info = sys.exc_info()
+ self.handle_exception(exc_info, source_hint=source)
+
+ def _parse(self, source, name, filename):
+ """Internal parsing function used by `parse` and `compile`."""
+ return Parser(self, source, name, encode_filename(filename)).parse()
+
+ def lex(self, source, name=None, filename=None):
+ """Lex the given sourcecode and return a generator that yields
+ tokens as tuples in the form ``(lineno, token_type, value)``.
+ This can be useful for :ref:`extension development <writing-extensions>`
+ and debugging templates.
+
+ This does not perform preprocessing. If you want the preprocessing
+ of the extensions to be applied you have to filter source through
+ the :meth:`preprocess` method.
+ """
+ source = text_type(source)
+ try:
+ return self.lexer.tokeniter(source, name, filename)
+ except TemplateSyntaxError:
+ exc_info = sys.exc_info()
+ self.handle_exception(exc_info, source_hint=source)
+
+ def preprocess(self, source, name=None, filename=None):
+ """Preprocesses the source with all extensions. This is automatically
+ called for all parsing and compiling methods but *not* for :meth:`lex`
+ because there you usually only want the actual source tokenized.
+ """
+ return reduce(lambda s, e: e.preprocess(s, name, filename),
+ self.iter_extensions(), text_type(source))
+
+ def _tokenize(self, source, name, filename=None, state=None):
+ """Called by the parser to do the preprocessing and filtering
+ for all the extensions. Returns a :class:`~jinja2.lexer.TokenStream`.
+ """
+ source = self.preprocess(source, name, filename)
+ stream = self.lexer.tokenize(source, name, filename, state)
+ for ext in self.iter_extensions():
+ stream = ext.filter_stream(stream)
+ if not isinstance(stream, TokenStream):
+ stream = TokenStream(stream, name, filename)
+ return stream
+
+ def _generate(self, source, name, filename, defer_init=False):
+ """Internal hook that can be overridden to hook a different generate
+ method in.
+
+ .. versionadded:: 2.5
+ """
+ return generate(source, self, name, filename, defer_init=defer_init)
+
+ def _compile(self, source, filename):
+ """Internal hook that can be overridden to hook a different compile
+ method in.
+
+ .. versionadded:: 2.5
+ """
+ return compile(source, filename, 'exec')
+
+ @internalcode
+ def compile(self, source, name=None, filename=None, raw=False,
+ defer_init=False):
+ """Compile a node or template source code. The `name` parameter is
+ the load name of the template after it was joined using
+ :meth:`join_path` if necessary, not the filename on the file system.
+ the `filename` parameter is the estimated filename of the template on
+ the file system. If the template came from a database or memory this
+ can be omitted.
+
+ The return value of this method is a python code object. If the `raw`
+ parameter is `True` the return value will be a string with python
+ code equivalent to the bytecode returned otherwise. This method is
+ mainly used internally.
+
+ `defer_init` is use internally to aid the module code generator. This
+ causes the generated code to be able to import without the global
+ environment variable to be set.
+
+ .. versionadded:: 2.4
+ `defer_init` parameter added.
+ """
+ source_hint = None
+ try:
+ if isinstance(source, string_types):
+ source_hint = source
+ source = self._parse(source, name, filename)
+ if self.optimized:
+ source = optimize(source, self)
+ source = self._generate(source, name, filename,
+ defer_init=defer_init)
+ if raw:
+ return source
+ if filename is None:
+ filename = '<template>'
+ else:
+ filename = encode_filename(filename)
+ return self._compile(source, filename)
+ except TemplateSyntaxError:
+ exc_info = sys.exc_info()
+ self.handle_exception(exc_info, source_hint=source)
+
+ def compile_expression(self, source, undefined_to_none=True):
+ """A handy helper method that returns a callable that accepts keyword
+ arguments that appear as variables in the expression. If called it
+ returns the result of the expression.
+
+ This is useful if applications want to use the same rules as Jinja
+ in template "configuration files" or similar situations.
+
+ Example usage:
+
+ >>> env = Environment()
+ >>> expr = env.compile_expression('foo == 42')
+ >>> expr(foo=23)
+ False
+ >>> expr(foo=42)
+ True
+
+ Per default the return value is converted to `None` if the
+ expression returns an undefined value. This can be changed
+ by setting `undefined_to_none` to `False`.
+
+ >>> env.compile_expression('var')() is None
+ True
+ >>> env.compile_expression('var', undefined_to_none=False)()
+ Undefined
+
+ .. versionadded:: 2.1
+ """
+ parser = Parser(self, source, state='variable')
+ exc_info = None
+ try:
+ expr = parser.parse_expression()
+ if not parser.stream.eos:
+ raise TemplateSyntaxError('chunk after expression',
+ parser.stream.current.lineno,
+ None, None)
+ expr.set_environment(self)
+ except TemplateSyntaxError:
+ exc_info = sys.exc_info()
+ if exc_info is not None:
+ self.handle_exception(exc_info, source_hint=source)
+ body = [nodes.Assign(nodes.Name('result', 'store'), expr, lineno=1)]
+ template = self.from_string(nodes.Template(body, lineno=1))
+ return TemplateExpression(template, undefined_to_none)
+
+ def compile_templates(self, target, extensions=None, filter_func=None,
+ zip='deflated', log_function=None,
+ ignore_errors=True, py_compile=False):
+ """Finds all the templates the loader can find, compiles them
+ and stores them in `target`. If `zip` is `None`, instead of in a
+ zipfile, the templates will be will be stored in a directory.
+ By default a deflate zip algorithm is used, to switch to
+ the stored algorithm, `zip` can be set to ``'stored'``.
+
+ `extensions` and `filter_func` are passed to :meth:`list_templates`.
+ Each template returned will be compiled to the target folder or
+ zipfile.
+
+ By default template compilation errors are ignored. In case a
+ log function is provided, errors are logged. If you want template
+ syntax errors to abort the compilation you can set `ignore_errors`
+ to `False` and you will get an exception on syntax errors.
+
+ If `py_compile` is set to `True` .pyc files will be written to the
+ target instead of standard .py files. This flag does not do anything
+ on pypy and Python 3 where pyc files are not picked up by itself and
+ don't give much benefit.
+
+ .. versionadded:: 2.4
+ """
+ from jinja2.loaders import ModuleLoader
+
+ if log_function is None:
+ log_function = lambda x: None
+
+ if py_compile:
+ if not PY2 or PYPY:
+ from warnings import warn
+ warn(Warning('py_compile has no effect on pypy or Python 3'))
+ py_compile = False
+ else:
+ import imp, marshal
+ py_header = imp.get_magic() + \
+ u'\xff\xff\xff\xff'.encode('iso-8859-15')
+
+ # Python 3.3 added a source filesize to the header
+ if sys.version_info >= (3, 3):
+ py_header += u'\x00\x00\x00\x00'.encode('iso-8859-15')
+
+ def write_file(filename, data, mode):
+ if zip:
+ info = ZipInfo(filename)
+ info.external_attr = 0o755 << 16
+ zip_file.writestr(info, data)
+ else:
+ f = open(os.path.join(target, filename), mode)
+ try:
+ f.write(data)
+ finally:
+ f.close()
+
+ if zip is not None:
+ from zipfile import ZipFile, ZipInfo, ZIP_DEFLATED, ZIP_STORED
+ zip_file = ZipFile(target, 'w', dict(deflated=ZIP_DEFLATED,
+ stored=ZIP_STORED)[zip])
+ log_function('Compiling into Zip archive "%s"' % target)
+ else:
+ if not os.path.isdir(target):
+ os.makedirs(target)
+ log_function('Compiling into folder "%s"' % target)
+
+ try:
+ for name in self.list_templates(extensions, filter_func):
+ source, filename, _ = self.loader.get_source(self, name)
+ try:
+ code = self.compile(source, name, filename, True, True)
+ except TemplateSyntaxError as e:
+ if not ignore_errors:
+ raise
+ log_function('Could not compile "%s": %s' % (name, e))
+ continue
+
+ filename = ModuleLoader.get_module_filename(name)
+
+ if py_compile:
+ c = self._compile(code, encode_filename(filename))
+ write_file(filename + 'c', py_header +
+ marshal.dumps(c), 'wb')
+ log_function('Byte-compiled "%s" as %s' %
+ (name, filename + 'c'))
+ else:
+ write_file(filename, code, 'w')
+ log_function('Compiled "%s" as %s' % (name, filename))
+ finally:
+ if zip:
+ zip_file.close()
+
+ log_function('Finished compiling templates')
+
+ def list_templates(self, extensions=None, filter_func=None):
+ """Returns a list of templates for this environment. This requires
+ that the loader supports the loader's
+ :meth:`~BaseLoader.list_templates` method.
+
+ If there are other files in the template folder besides the
+ actual templates, the returned list can be filtered. There are two
+ ways: either `extensions` is set to a list of file extensions for
+ templates, or a `filter_func` can be provided which is a callable that
+ is passed a template name and should return `True` if it should end up
+ in the result list.
+
+ If the loader does not support that, a :exc:`TypeError` is raised.
+
+ .. versionadded:: 2.4
+ """
+ x = self.loader.list_templates()
+ if extensions is not None:
+ if filter_func is not None:
+ raise TypeError('either extensions or filter_func '
+ 'can be passed, but not both')
+ filter_func = lambda x: '.' in x and \
+ x.rsplit('.', 1)[1] in extensions
+ if filter_func is not None:
+ x = ifilter(filter_func, x)
+ return x
+
+ def handle_exception(self, exc_info=None, rendered=False, source_hint=None):
+ """Exception handling helper. This is used internally to either raise
+ rewritten exceptions or return a rendered traceback for the template.
+ """
+ global _make_traceback
+ if exc_info is None:
+ exc_info = sys.exc_info()
+
+ # the debugging module is imported when it's used for the first time.
+ # we're doing a lot of stuff there and for applications that do not
+ # get any exceptions in template rendering there is no need to load
+ # all of that.
+ if _make_traceback is None:
+ from jinja2.debug import make_traceback as _make_traceback
+ traceback = _make_traceback(exc_info, source_hint)
+ if rendered and self.exception_formatter is not None:
+ return self.exception_formatter(traceback)
+ if self.exception_handler is not None:
+ self.exception_handler(traceback)
+ exc_type, exc_value, tb = traceback.standard_exc_info
+ reraise(exc_type, exc_value, tb)
+
+ def join_path(self, template, parent):
+ """Join a template with the parent. By default all the lookups are
+ relative to the loader root so this method returns the `template`
+ parameter unchanged, but if the paths should be relative to the
+ parent template, this function can be used to calculate the real
+ template name.
+
+ Subclasses may override this method and implement template path
+ joining here.
+ """
+ return template
+
+ @internalcode
+ def _load_template(self, name, globals):
+ if self.loader is None:
+ raise TypeError('no loader for this environment specified')
+ if self.cache is not None:
+ template = self.cache.get(name)
+ if template is not None and (not self.auto_reload or \
+ template.is_up_to_date):
+ return template
+ template = self.loader.load(self, name, globals)
+ if self.cache is not None:
+ self.cache[name] = template
+ return template
+
+ @internalcode
+ def get_template(self, name, parent=None, globals=None):
+ """Load a template from the loader. If a loader is configured this
+ method ask the loader for the template and returns a :class:`Template`.
+ If the `parent` parameter is not `None`, :meth:`join_path` is called
+ to get the real template name before loading.
+
+ The `globals` parameter can be used to provide template wide globals.
+ These variables are available in the context at render time.
+
+ If the template does not exist a :exc:`TemplateNotFound` exception is
+ raised.
+
+ .. versionchanged:: 2.4
+ If `name` is a :class:`Template` object it is returned from the
+ function unchanged.
+ """
+ if isinstance(name, Template):
+ return name
+ if parent is not None:
+ name = self.join_path(name, parent)
+ return self._load_template(name, self.make_globals(globals))
+
+ @internalcode
+ def select_template(self, names, parent=None, globals=None):
+ """Works like :meth:`get_template` but tries a number of templates
+ before it fails. If it cannot find any of the templates, it will
+ raise a :exc:`TemplatesNotFound` exception.
+
+ .. versionadded:: 2.3
+
+ .. versionchanged:: 2.4
+ If `names` contains a :class:`Template` object it is returned
+ from the function unchanged.
+ """
+ if not names:
+ raise TemplatesNotFound(message=u'Tried to select from an empty list '
+ u'of templates.')
+ globals = self.make_globals(globals)
+ for name in names:
+ if isinstance(name, Template):
+ return name
+ if parent is not None:
+ name = self.join_path(name, parent)
+ try:
+ return self._load_template(name, globals)
+ except TemplateNotFound:
+ pass
+ raise TemplatesNotFound(names)
+
+ @internalcode
+ def get_or_select_template(self, template_name_or_list,
+ parent=None, globals=None):
+ """Does a typecheck and dispatches to :meth:`select_template`
+ if an iterable of template names is given, otherwise to
+ :meth:`get_template`.
+
+ .. versionadded:: 2.3
+ """
+ if isinstance(template_name_or_list, string_types):
+ return self.get_template(template_name_or_list, parent, globals)
+ elif isinstance(template_name_or_list, Template):
+ return template_name_or_list
+ return self.select_template(template_name_or_list, parent, globals)
+
+ def from_string(self, source, globals=None, template_class=None):
+ """Load a template from a string. This parses the source given and
+ returns a :class:`Template` object.
+ """
+ globals = self.make_globals(globals)
+ cls = template_class or self.template_class
+ return cls.from_code(self, self.compile(source), globals, None)
+
+ def make_globals(self, d):
+ """Return a dict for the globals."""
+ if not d:
+ return self.globals
+ return dict(self.globals, **d)
+
+
+class Template(object):
+ """The central template object. This class represents a compiled template
+ and is used to evaluate it.
+
+ Normally the template object is generated from an :class:`Environment` but
+ it also has a constructor that makes it possible to create a template
+ instance directly using the constructor. It takes the same arguments as
+ the environment constructor but it's not possible to specify a loader.
+
+ Every template object has a few methods and members that are guaranteed
+ to exist. However it's important that a template object should be
+ considered immutable. Modifications on the object are not supported.
+
+ Template objects created from the constructor rather than an environment
+ do have an `environment` attribute that points to a temporary environment
+ that is probably shared with other templates created with the constructor
+ and compatible settings.
+
+ >>> template = Template('Hello {{ name }}!')
+ >>> template.render(name='John Doe')
+ u'Hello John Doe!'
+
+ >>> stream = template.stream(name='John Doe')
+ >>> stream.next()
+ u'Hello John Doe!'
+ >>> stream.next()
+ Traceback (most recent call last):
+ ...
+ StopIteration
+ """
+
+ def __new__(cls, source,
+ block_start_string=BLOCK_START_STRING,
+ block_end_string=BLOCK_END_STRING,
+ variable_start_string=VARIABLE_START_STRING,
+ variable_end_string=VARIABLE_END_STRING,
+ comment_start_string=COMMENT_START_STRING,
+ comment_end_string=COMMENT_END_STRING,
+ line_statement_prefix=LINE_STATEMENT_PREFIX,
+ line_comment_prefix=LINE_COMMENT_PREFIX,
+ trim_blocks=TRIM_BLOCKS,
+ lstrip_blocks=LSTRIP_BLOCKS,
+ newline_sequence=NEWLINE_SEQUENCE,
+ keep_trailing_newline=KEEP_TRAILING_NEWLINE,
+ extensions=(),
+ optimized=True,
+ undefined=Undefined,
+ finalize=None,
+ autoescape=False):
+ env = get_spontaneous_environment(
+ block_start_string, block_end_string, variable_start_string,
+ variable_end_string, comment_start_string, comment_end_string,
+ line_statement_prefix, line_comment_prefix, trim_blocks,
+ lstrip_blocks, newline_sequence, keep_trailing_newline,
+ frozenset(extensions), optimized, undefined, finalize, autoescape,
+ None, 0, False, None)
+ return env.from_string(source, template_class=cls)
+
+ @classmethod
+ def from_code(cls, environment, code, globals, uptodate=None):
+ """Creates a template object from compiled code and the globals. This
+ is used by the loaders and environment to create a template object.
+ """
+ namespace = {
+ 'environment': environment,
+ '__file__': code.co_filename
+ }
+ exec(code, namespace)
+ rv = cls._from_namespace(environment, namespace, globals)
+ rv._uptodate = uptodate
+ return rv
+
+ @classmethod
+ def from_module_dict(cls, environment, module_dict, globals):
+ """Creates a template object from a module. This is used by the
+ module loader to create a template object.
+
+ .. versionadded:: 2.4
+ """
+ return cls._from_namespace(environment, module_dict, globals)
+
+ @classmethod
+ def _from_namespace(cls, environment, namespace, globals):
+ t = object.__new__(cls)
+ t.environment = environment
+ t.globals = globals
+ t.name = namespace['name']
+ t.filename = namespace['__file__']
+ t.blocks = namespace['blocks']
+
+ # render function and module
+ t.root_render_func = namespace['root']
+ t._module = None
+
+ # debug and loader helpers
+ t._debug_info = namespace['debug_info']
+ t._uptodate = None
+
+ # store the reference
+ namespace['environment'] = environment
+ namespace['__jinja_template__'] = t
+
+ return t
+
+ def render(self, *args, **kwargs):
+ """This method accepts the same arguments as the `dict` constructor:
+ A dict, a dict subclass or some keyword arguments. If no arguments
+ are given the context will be empty. These two calls do the same::
+
+ template.render(knights='that say nih')
+ template.render({'knights': 'that say nih'})
+
+ This will return the rendered template as unicode string.
+ """
+ vars = dict(*args, **kwargs)
+ try:
+ return concat(self.root_render_func(self.new_context(vars)))
+ except Exception:
+ exc_info = sys.exc_info()
+ return self.environment.handle_exception(exc_info, True)
+
+ def stream(self, *args, **kwargs):
+ """Works exactly like :meth:`generate` but returns a
+ :class:`TemplateStream`.
+ """
+ return TemplateStream(self.generate(*args, **kwargs))
+
+ def generate(self, *args, **kwargs):
+ """For very large templates it can be useful to not render the whole
+ template at once but evaluate each statement after another and yield
+ piece for piece. This method basically does exactly that and returns
+ a generator that yields one item after another as unicode strings.
+
+ It accepts the same arguments as :meth:`render`.
+ """
+ vars = dict(*args, **kwargs)
+ try:
+ for event in self.root_render_func(self.new_context(vars)):
+ yield event
+ except Exception:
+ exc_info = sys.exc_info()
+ else:
+ return
+ yield self.environment.handle_exception(exc_info, True)
+
+ def new_context(self, vars=None, shared=False, locals=None):
+ """Create a new :class:`Context` for this template. The vars
+ provided will be passed to the template. Per default the globals
+ are added to the context. If shared is set to `True` the data
+ is passed as it to the context without adding the globals.
+
+ `locals` can be a dict of local variables for internal usage.
+ """
+ return new_context(self.environment, self.name, self.blocks,
+ vars, shared, self.globals, locals)
+
+ def make_module(self, vars=None, shared=False, locals=None):
+ """This method works like the :attr:`module` attribute when called
+ without arguments but it will evaluate the template on every call
+ rather than caching it. It's also possible to provide
+ a dict which is then used as context. The arguments are the same
+ as for the :meth:`new_context` method.
+ """
+ return TemplateModule(self, self.new_context(vars, shared, locals))
+
+ @property
+ def module(self):
+ """The template as module. This is used for imports in the
+ template runtime but is also useful if one wants to access
+ exported template variables from the Python layer:
+
+ >>> t = Template('{% macro foo() %}42{% endmacro %}23')
+ >>> unicode(t.module)
+ u'23'
+ >>> t.module.foo()
+ u'42'
+ """
+ if self._module is not None:
+ return self._module
+ self._module = rv = self.make_module()
+ return rv
+
+ def get_corresponding_lineno(self, lineno):
+ """Return the source line number of a line number in the
+ generated bytecode as they are not in sync.
+ """
+ for template_line, code_line in reversed(self.debug_info):
+ if code_line <= lineno:
+ return template_line
+ return 1
+
+ @property
+ def is_up_to_date(self):
+ """If this variable is `False` there is a newer version available."""
+ if self._uptodate is None:
+ return True
+ return self._uptodate()
+
+ @property
+ def debug_info(self):
+ """The debug info mapping."""
+ return [tuple(imap(int, x.split('='))) for x in
+ self._debug_info.split('&')]
+
+ def __repr__(self):
+ if self.name is None:
+ name = 'memory:%x' % id(self)
+ else:
+ name = repr(self.name)
+ return '<%s %s>' % (self.__class__.__name__, name)
+
+
+@implements_to_string
+class TemplateModule(object):
+ """Represents an imported template. All the exported names of the
+ template are available as attributes on this object. Additionally
+ converting it into an unicode- or bytestrings renders the contents.
+ """
+
+ def __init__(self, template, context):
+ self._body_stream = list(template.root_render_func(context))
+ self.__dict__.update(context.get_exported())
+ self.__name__ = template.name
+
+ def __html__(self):
+ return Markup(concat(self._body_stream))
+
+ def __str__(self):
+ return concat(self._body_stream)
+
+ def __repr__(self):
+ if self.__name__ is None:
+ name = 'memory:%x' % id(self)
+ else:
+ name = repr(self.__name__)
+ return '<%s %s>' % (self.__class__.__name__, name)
+
+
+class TemplateExpression(object):
+ """The :meth:`jinja2.Environment.compile_expression` method returns an
+ instance of this object. It encapsulates the expression-like access
+ to the template with an expression it wraps.
+ """
+
+ def __init__(self, template, undefined_to_none):
+ self._template = template
+ self._undefined_to_none = undefined_to_none
+
+ def __call__(self, *args, **kwargs):
+ context = self._template.new_context(dict(*args, **kwargs))
+ consume(self._template.root_render_func(context))
+ rv = context.vars['result']
+ if self._undefined_to_none and isinstance(rv, Undefined):
+ rv = None
+ return rv
+
+
+@implements_iterator
+class TemplateStream(object):
+ """A template stream works pretty much like an ordinary python generator
+ but it can buffer multiple items to reduce the number of total iterations.
+ Per default the output is unbuffered which means that for every unbuffered
+ instruction in the template one unicode string is yielded.
+
+ If buffering is enabled with a buffer size of 5, five items are combined
+ into a new unicode string. This is mainly useful if you are streaming
+ big templates to a client via WSGI which flushes after each iteration.
+ """
+
+ def __init__(self, gen):
+ self._gen = gen
+ self.disable_buffering()
+
+ def dump(self, fp, encoding=None, errors='strict'):
+ """Dump the complete stream into a file or file-like object.
+ Per default unicode strings are written, if you want to encode
+ before writing specify an `encoding`.
+
+ Example usage::
+
+ Template('Hello {{ name }}!').stream(name='foo').dump('hello.html')
+ """
+ close = False
+ if isinstance(fp, string_types):
+ fp = open(fp, encoding is None and 'w' or 'wb')
+ close = True
+ try:
+ if encoding is not None:
+ iterable = (x.encode(encoding, errors) for x in self)
+ else:
+ iterable = self
+ if hasattr(fp, 'writelines'):
+ fp.writelines(iterable)
+ else:
+ for item in iterable:
+ fp.write(item)
+ finally:
+ if close:
+ fp.close()
+
+ def disable_buffering(self):
+ """Disable the output buffering."""
+ self._next = get_next(self._gen)
+ self.buffered = False
+
+ def enable_buffering(self, size=5):
+ """Enable buffering. Buffer `size` items before yielding them."""
+ if size <= 1:
+ raise ValueError('buffer size too small')
+
+ def generator(next):
+ buf = []
+ c_size = 0
+ push = buf.append
+
+ while 1:
+ try:
+ while c_size < size:
+ c = next()
+ push(c)
+ if c:
+ c_size += 1
+ except StopIteration:
+ if not c_size:
+ return
+ yield concat(buf)
+ del buf[:]
+ c_size = 0
+
+ self.buffered = True
+ self._next = get_next(generator(get_next(self._gen)))
+
+ def __iter__(self):
+ return self
+
+ def __next__(self):
+ return self._next()
+
+
+# hook in default template class. if anyone reads this comment: ignore that
+# it's possible to use custom templates ;-)
+Environment.template_class = Template
