From 238e4bbad7712ccc3a3ea4a5b09c63bd147c692e Mon Sep 17 00:00:00 2001
From: René Kijewski <rene.kijewski@fu-berlin.de>
Date: Thu, 28 Sep 2023 17:09:29 +0200
Subject: Limit nesting in parser nodes, too

---
 askama_parser/src/lib.rs  | 15 +++++++++++++++
 askama_parser/src/node.rs | 12 ++++++++----
 2 files changed, 23 insertions(+), 4 deletions(-)

(limited to 'askama_parser/src')

diff --git a/askama_parser/src/lib.rs b/askama_parser/src/lib.rs
index de88a20..3428735 100644
--- a/askama_parser/src/lib.rs
+++ b/askama_parser/src/lib.rs
@@ -255,6 +255,7 @@ fn path_or_identifier(i: &str) -> IResult<&str, PathOrIdentifier<'_>> {
 struct State<'a> {
     syntax: &'a Syntax<'a>,
     loop_depth: Cell<usize>,
+    level: Cell<Level>,
 }
 
 impl<'a> State<'a> {
@@ -262,9 +263,19 @@ impl<'a> State<'a> {
         State {
             syntax,
             loop_depth: Cell::new(0),
+            level: Cell::new(Level::default()),
         }
     }
 
+    fn nest<'b>(&self, i: &'b str) -> Result<(), nom::Err<nom::error::Error<&'b str>>> {
+        self.level.set(self.level.get().nest(i)?);
+        Ok(())
+    }
+
+    fn leave(&self) {
+        self.level.set(self.level.get().leave());
+    }
+
     fn tag_block_start<'i>(&self, i: &'i str) -> IResult<&'i str, &'i str> {
         tag(self.syntax.block_start)(i)
     }
@@ -337,5 +348,9 @@ impl Level {
         Ok(Level(self.0 + 1))
     }
 
+    fn leave(&self) -> Self {
+        Level(self.0 - 1)
+    }
+
     const MAX_DEPTH: u8 = 64;
 }
diff --git a/askama_parser/src/node.rs b/askama_parser/src/node.rs
index f25f25a..1909f6c 100644
--- a/askama_parser/src/node.rs
+++ b/askama_parser/src/node.rs
@@ -47,7 +47,7 @@ impl<'a> Node<'a> {
     }
 
     fn parse(i: &'a str, s: &State<'_>) -> IResult<&'a str, Self> {
-        let mut p = tuple((
+        let mut p = delimited(
             |i| s.tag_block_start(i),
             alt((
                 map(Call::parse, Self::Call),
@@ -65,9 +65,13 @@ impl<'a> Node<'a> {
                 |i| Self::r#continue(i, s),
             )),
             cut(|i| s.tag_block_end(i)),
-        ));
-        let (i, (_, contents, _)) = p(i)?;
-        Ok((i, contents))
+        );
+
+        s.nest(i)?;
+        let result = p(i);
+        s.leave();
+
+        result
     }
 
     fn r#break(i: &'a str, s: &State<'_>) -> IResult<&'a str, Self> {
-- 
cgit