setup

Cargo.lock

@@ -2,6 +2,51 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "arbitrary"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c38b6b6b79f671c25e1a3e785b7b82d7562ffc9cd3efdc98627e5668a2472490"
+
 [[package]]
 name = "fuzz-rustc-ast"
 version = "0.1.0"
+dependencies = [
+ "arbitrary",
+ "syn",
+]
+
+[[package]]
+name = "proc-macro2"
+version = "1.0.36"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c7342d5883fbccae1cc37a2353b09c87c9b0f3afd73f5fb9bba687a1f733b029"
+dependencies = [
+ "unicode-xid",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "864d3e96a899863136fc6e99f3d7cae289dafe43bf2c5ac19b70df7210c0a145"
+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "syn"
+version = "1.0.88"
+source = "git+https://github.com/Nilstrieb/syn?branch=arbitrary#a0860e2ae754ade1340683bc54e403540202484b"
+dependencies = [
+ "arbitrary",
+ "proc-macro2",
+ "quote",
+ "unicode-xid",
+]
+
+[[package]]
+name = "unicode-xid"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8ccb82d61f80a663efe1f787a51b16b5a51e3314d6ac365b08639f52387b33f3"

Cargo.toml

@@ -3,6 +3,9 @@ name = "fuzz-rustc-ast"
 version = "0.1.0"
 edition = "2021"
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
 [dependencies]
+arbitrary = "1.1.0"
+# fork of syn with the arbitrary trait impls
+syn = { git = "https://github.com/Nilstrieb/syn", branch = "arbitrary", features = ["full", "arbitrary"] }
+
+[features]

src/main.rs

@@ -1,3 +1,11 @@
+use arbitrary::Arbitrary;
+use std::path::PathBuf;
+
 fn main() {
-    println!("Hello, world!");
+    let data = std::fs::read(PathBuf::from(file!()).parent().unwrap().join("Cargo.toml")).unwrap();
+    let mut unstructured = arbitrary::Unstructured::new(&data);
+
+    let ast = syn::Item::arbitrary(&mut unstructured);
+
+    println!("{ast}");
 }