pulldown-cmark panics on first pass when enabling definition-lists #973
Description
I'm not sure if nested definition lists are valid, but using pulldown-cmark 0.12.2 and the following input causes a panic:
level one!
:
level two!
:
level three!
:
new level one!
:Here's a small program that reproduces the issue:
use pulldown_cmark::{Options, Parser};
static INPUT: &str = "
level one!
:
level two!
:
level three!
:
new level one!
:
";
fn main() {
let options = Options::ENABLE_DEFINITION_LIST;
let parser = Parser::new_ext(INPUT, options);
for _ in parser {}
}Traceback
thread 'main' panicked at /Users/ytmimi/.cargo/registry/src/index.crates.io-6f17d22bba15001f/pulldown-cmark-0.12.2/src/firstpass.rs:1540:38:
called `Option::unwrap()` on a `None` value
stack backtrace:
0: rust_begin_unwind
at /rustc/e7c0d2750726c1f08b1de6956248ec78c4a97af6/library/std/src/panicking.rs:665:5
1: core::panicking::panic_fmt
at /rustc/e7c0d2750726c1f08b1de6956248ec78c4a97af6/library/core/src/panicking.rs:74:14
2: core::panicking::panic
at /rustc/e7c0d2750726c1f08b1de6956248ec78c4a97af6/library/core/src/panicking.rs:148:5
3: core::option::unwrap_failed
at /rustc/e7c0d2750726c1f08b1de6956248ec78c4a97af6/library/core/src/option.rs:2012:5
4: core::option::Option<T>::unwrap
at /Users/ytmimi/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/core/src/option.rs:972:21
5: pulldown_cmark::firstpass::FirstPass::pop
at /Users/ytmimi/.cargo/registry/src/index.crates.io-6f17d22bba15001f/pulldown-cmark-0.12.2/src/firstpass.rs:1540:22
6: pulldown_cmark::firstpass::FirstPass::parse_block
at /Users/ytmimi/.cargo/registry/src/index.crates.io-6f17d22bba15001f/pulldown-cmark-0.12.2/src/firstpass.rs:99:13
7: pulldown_cmark::firstpass::FirstPass::run
at /Users/ytmimi/.cargo/registry/src/index.crates.io-6f17d22bba15001f/pulldown-cmark-0.12.2/src/firstpass.rs:76:18
8: pulldown_cmark::firstpass::run_first_pass
at /Users/ytmimi/.cargo/registry/src/index.crates.io-6f17d22bba15001f/pulldown-cmark-0.12.2/src/firstpass.rs:41:5
9: pulldown_cmark::parse::Parser<F>::new_with_broken_link_callback
at /Users/ytmimi/.cargo/registry/src/index.crates.io-6f17d22bba15001f/pulldown-cmark-0.12.2/src/parse.rs:270:34
10: pulldown_cmark::parse::Parser::new_ext
at /Users/ytmimi/.cargo/registry/src/index.crates.io-6f17d22bba15001f/pulldown-cmark-0.12.2/src/parse.rs:255:9
11: example::main
at ./src/example.rs:19:18
12: core::ops::function::FnOnce::call_once
at /Users/ytmimi/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/core/src/ops/function.rs:250:5