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Diffstat (limited to 'venv/lib/python3.11/site-packages/jinja2/optimizer.py')
-rw-r--r-- | venv/lib/python3.11/site-packages/jinja2/optimizer.py | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/venv/lib/python3.11/site-packages/jinja2/optimizer.py b/venv/lib/python3.11/site-packages/jinja2/optimizer.py new file mode 100644 index 0000000..fe10107 --- /dev/null +++ b/venv/lib/python3.11/site-packages/jinja2/optimizer.py @@ -0,0 +1,47 @@ +"""The optimizer tries to constant fold expressions and modify the AST +in place so that it should be faster to evaluate. + +Because the AST does not contain all the scoping information and the +compiler has to find that out, we cannot do all the optimizations we +want. For example, loop unrolling doesn't work because unrolled loops +would have a different scope. The solution would be a second syntax tree +that stored the scoping rules. +""" +import typing as t + +from . import nodes +from .visitor import NodeTransformer + +if t.TYPE_CHECKING: + from .environment import Environment + + +def optimize(node: nodes.Node, environment: "Environment") -> nodes.Node: + """The context hint can be used to perform an static optimization + based on the context given.""" + optimizer = Optimizer(environment) + return t.cast(nodes.Node, optimizer.visit(node)) + + +class Optimizer(NodeTransformer): + def __init__(self, environment: "t.Optional[Environment]") -> None: + self.environment = environment + + def generic_visit( + self, node: nodes.Node, *args: t.Any, **kwargs: t.Any + ) -> nodes.Node: + node = super().generic_visit(node, *args, **kwargs) + + # Do constant folding. Some other nodes besides Expr have + # as_const, but folding them causes errors later on. + if isinstance(node, nodes.Expr): + try: + return nodes.Const.from_untrusted( + node.as_const(args[0] if args else None), + lineno=node.lineno, + environment=self.environment, + ) + except nodes.Impossible: + pass + + return node |