Draft: Add fuzzing to wavedrom

README.md

@@ -55,6 +55,15 @@ cd ./tests
 ./run [path/to/skin.json5]
 ```
 
+## Fuzzing
+
+This project is fuzzed with [`cargo-fuzz`][cargo-fuzz]. This improves the
+stability of the project.
+
+```bash
+cargo +nightly fuzz run wavejson-render
+```
+
 ## MSRV
 
 This crate currently only compiles with Rust 1.70. To select that version use:
@@ -83,4 +92,5 @@ Licensed under a [MIT License](./LICENSE). The demo website utilizes icons from
 [cli]: ./wavedrom-cli
 [mdbook-wavedrom]: ./mdbook-wavedrom
 [dtd]: https://en.wikipedia.org/wiki/Digital_timing_diagram
-[book]: https://coastalwhite.github.io/wavedrom-rs
+[book]: https://coastalwhite.github.io/wavedrom-rs
+[cargo-fuzz]: https://github.com/rust-fuzz/cargo-fuzz

fuzz/.gitignore

@@ -0,0 +1,4 @@
+target
+corpus
+artifacts
+coverage

fuzz/Cargo.toml

@@ -0,0 +1,28 @@
+[package]
+name = "wavedrom-fuzz"
+version = "0.0.0"
+publish = false
+edition = "2021"
+
+[package.metadata]
+cargo-fuzz = true
+
+[dependencies]
+libfuzzer-sys = "0.4"
+
+[dependencies.wavedrom]
+path = "../wavedrom"
+features = ["arbitrary"]
+
+# Prevent this from interfering with workspaces
+[workspace]
+members = ["."]
+
+[profile.release]
+debug = 1
+
+[[bin]]
+name = "wavejson-render"
+path = "fuzz_targets/wavejson_render.rs"
+test = false
+doc = false

fuzz/fuzz_targets/wavejson_render.rs

@@ -0,0 +1,16 @@
+#![no_main]
+
+use libfuzzer_sys::fuzz_target;
+
+use wavedrom::wavejson::WaveJson;
+use wavedrom::Figure;
+
+fuzz_target!(|data: WaveJson| {
+    let figure = Figure::from(data);
+
+    let Figure::Signal(figure) = figure;
+
+    let assembled = figure.assemble();
+    let mut writer = Vec::new();
+    let _ = assembled.write_svg(&mut writer);
+});

wavedrom/Cargo.toml

@@ -31,6 +31,11 @@ optional = true
 version = "1.0"
 optional = true
 
+[dependencies.arbitrary]
+version = "1.3.0"
+optional = true
+features = ["derive"]
+
 [features]
 default = ["json5", "embed_font", "skins"]
 embed_font = ["dep:ttf-parser"]

wavedrom/src/wavejson/mod.rs

@@ -10,6 +10,7 @@ use crate::Figure;
 pub mod signal;
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 #[serde(untagged)]
 pub enum WaveJson {
     Signal(SignalJson),