test(fuzz): fuzz xml5ever (#557)

* test(fuzz): fuzz xml5ever

* style: drop newline on */fuzz/.gitignore

html5ever/fuzz/.gitignore

@@ -1,4 +1,3 @@
-
 target
 corpus
 artifacts

xml5ever/fuzz/.gitignore

@@ -0,0 +1,3 @@
+target
+corpus
+artifacts

xml5ever/fuzz/Cargo.toml

@@ -0,0 +1,27 @@
+
+[package]
+name = "xml5ever-fuzz"
+version = "0.0.0"
+authors = ["David Korczynski <david@adalogics.com>"]
+publish = false
+edition = "2018"
+
+[package.metadata]
+cargo-fuzz = true
+
+[dependencies]
+libfuzzer-sys = "0.4.0"
+
+[dependencies.xml5ever]
+path = ".."
+
+[dependencies.markup5ever_rcdom]
+path = "../../rcdom/"
+
+# Prevent this from interfering with workspaces
+[workspace]
+members = ["."]
+
+[[bin]]
+name = "fuzz_document_parse"
+path = "fuzz_targets/fuzz_document_parse.rs"

xml5ever/fuzz/fuzz_targets/fuzz_document_parse.rs

@@ -0,0 +1,35 @@
+#![no_main]
+use libfuzzer_sys::fuzz_target;
+
+use markup5ever_rcdom::{RcDom, SerializableHandle};
+use std::io::BufReader;
+use xml5ever::driver::parse_document;
+use xml5ever::driver::XmlParseOpts;
+use xml5ever::serialize::serialize;
+use xml5ever::tendril::TendrilSink;
+use xml5ever::tree_builder::XmlTreeBuilderOpts;
+
+// Target inspired by the Rust-Fuzz project
+// https://github.com/rust-fuzz/targets
+fuzz_target!(|data: &[u8]| {
+    let opts = XmlParseOpts {
+        tree_builder: XmlTreeBuilderOpts {
+            ..Default::default()
+        },
+        ..Default::default()
+    };
+
+    let dom = parse_document(RcDom::default(), opts)
+        .from_utf8()
+        .read_from(&mut BufReader::new(data));
+
+    let dom = if let Ok(dom) = dom {
+        dom
+    } else {
+        return;
+    };
+
+    let mut out = std::io::sink();
+    let document: SerializableHandle = dom.document.into();
+    let _ = serialize(&mut out, &document, Default::default());
+});