From 2f465f6682d22abf81660af8c5bd10fcce5d988a Mon Sep 17 00:00:00 2001
From: misha <mkhachaiants@gmail.com>
Date: Sat, 26 Apr 2025 23:00:24 +0300
Subject: [PATCH] New fuzzer for strongly typed data structures

---
 fuzz/Cargo.toml                     |  7 +++
 fuzz/fuzz_targets/strongly_typed.rs | 91 +++++++++++++++++++++++++++++
 2 files changed, 98 insertions(+)
 create mode 100644 fuzz/fuzz_targets/strongly_typed.rs

diff --git a/fuzz/Cargo.toml b/fuzz/Cargo.toml
index 5fe38b679..cd637622d 100644
--- a/fuzz/Cargo.toml
+++ b/fuzz/Cargo.toml
@@ -11,9 +11,16 @@ cargo-fuzz = true
 [dependencies]
 libfuzzer-sys = "0.4"
 serde_json = { path = ".." }
+serde = { version = "1.0.194", features = ["derive"] }
 
 [[bin]]
 name = "from_slice"
 path = "fuzz_targets/from_slice.rs"
 test = false
 doc = false
+
+[[bin]]
+name = "strongly_typed"
+path = "fuzz_targets/strongly_typed.rs"
+test = false
+doc = false
diff --git a/fuzz/fuzz_targets/strongly_typed.rs b/fuzz/fuzz_targets/strongly_typed.rs
new file mode 100644
index 000000000..1b0e96992
--- /dev/null
+++ b/fuzz/fuzz_targets/strongly_typed.rs
@@ -0,0 +1,91 @@
+#![no_main]
+
+use libfuzzer_sys::fuzz_target;
+use serde::{Deserialize, Serialize};
+use serde_json::{from_slice, from_value, to_string};
+use std::collections::HashMap;
+
+#[derive(Serialize, Deserialize)]
+enum Enum {
+    A(u32),
+    B(i32, i32),
+    C { x: i32, y: i32 },
+    U,
+}
+
+#[derive(Serialize, Deserialize)]
+struct WrappedInt(i32);
+
+#[derive(Serialize, Deserialize)]
+struct Numbers {
+    a: Option<i8>,
+    b: Option<u8>,
+    c: Option<i16>,
+    d: Option<u16>,
+    e: Option<i32>,
+    f: Option<u32>,
+    g: Option<i64>,
+    h: Option<u64>,
+    i: Option<i128>,
+    j: Option<u128>,
+    k: Option<f32>,
+    l: Option<f64>,
+}
+
+#[derive(Serialize, Deserialize)]
+struct CommonTypes {
+    a: Option<char>,
+    b: Option<String>,
+    c: Option<bool>,
+}
+
+#[derive(Serialize, Deserialize)]
+struct Arrays {
+    a: Option<Vec<u8>>,
+    b: Option<[u8; 3]>,
+}
+
+#[derive(Serialize, Deserialize)]
+struct Maps {
+    a: Option<HashMap<String, i32>>,
+    b: Option<HashMap<char, i32>>,
+    c: Option<HashMap<i8, i32>>,
+    d: Option<HashMap<i16, i32>>,
+    e: Option<HashMap<i32, i32>>,
+    f: Option<HashMap<i64, i32>>,
+    g: Option<HashMap<i128, i32>>,
+    h: Option<HashMap<u8, i32>>,
+    i: Option<HashMap<u16, i32>>,
+    j: Option<HashMap<u32, i32>>,
+    k: Option<HashMap<u64, i32>>,
+    l: Option<HashMap<u128, i32>>,
+    o: Option<HashMap<bool, i32>>,
+}
+
+#[derive(Serialize, Deserialize)]
+struct Others {
+    a: Option<(f32, char, i8)>,
+    b: Option<Enum>,
+    c: Option<std::time::Duration>,
+    d: Option<std::time::SystemTime>,
+    e: Option<WrappedInt>,
+}
+
+#[derive(Deserialize, Serialize)]
+struct Data {
+    a: Option<Numbers>,
+    b: Option<Maps>,
+    c: Option<CommonTypes>,
+    d: Option<Arrays>,
+    e: Option<Others>,
+}
+
+fuzz_target!(|data: &[u8]| {
+    if let Ok(d) = from_slice::<Data>(data) {
+        let _ = to_string(&d);
+    }
+
+    if let Ok(value) = from_slice(data) {
+        let _ = from_value::<Data>(value);
+    }
+});