Include a serde no-std example (relates #148)

.github/workflows/ci.yml

@@ -57,11 +57,10 @@ jobs:
       fail-fast: false
       matrix:
         os: ['windows-latest', 'ubuntu-latest']
-        example: ['json']
+        example: ['json', 'serde']
     steps:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@nightly
-      - run: cargo build
       - run: cargo +nightly run -p no-std --example ${{matrix.example}}
 
   fuzz:

no-std/Cargo.toml

@@ -4,7 +4,8 @@ edition = "2021"
 publish = false
 
 [dependencies]
-musli = { path = "../crates/musli", default-features = false, features = ["json", "parse-full"] }
+musli = { path = "../crates/musli", default-features = false, features = ["json", "parse-full", "serde"] }
+serde = { version = "1.0.202", default-features = false, features = ["derive"] }
 
 [target.'cfg(unix)'.dependencies]
 compiler_builtins = { git = "https://github.com/rust-lang/compiler-builtins", features = ["mem"] }

no-std/examples/json.rs

@@ -1,37 +1,13 @@
 #![no_std]
 #![allow(internal_features)]
-#![feature(alloc_error_handler, start, core_intrinsics, lang_items, link_cfg)]
+#![feature(start, core_intrinsics, lang_items, link_cfg)]
+
+mod prelude;
 
 use musli::allocator::{Stack, StackBuffer};
 use musli::context::StackContext;
 use musli::{Decode, Encode};
 
-#[cfg(all(windows, target_env = "msvc"))]
-#[link(name = "msvcrt")]
-extern "C" {}
-
-#[cfg(unix)]
-#[link(name = "c")]
-extern "C" {}
-
-#[alloc_error_handler]
-fn err_handler(_: core::alloc::Layout) -> ! {
-    core::intrinsics::abort();
-}
-
-#[panic_handler]
-#[lang = "panic_impl"]
-fn rust_begin_panic(_: &core::panic::PanicInfo) -> ! {
-    core::intrinsics::abort();
-}
-
-#[lang = "eh_personality"]
-extern "C" fn eh_personality() {}
-
-#[cfg(unix)]
-#[no_mangle]
-pub extern "C" fn _Unwind_Resume() {}
-
 #[derive(Debug, Encode, Decode)]
 struct Value<'a> {
     name: &'a str,

no-std/examples/prelude.rs

@@ -0,0 +1,23 @@
+//! Helper module to set up everything you need in a no-std environment withotu
+//! alloc support.
+
+#[cfg(all(windows, target_env = "msvc"))]
+#[link(name = "msvcrt")]
+extern "C" {}
+
+#[cfg(unix)]
+#[link(name = "c")]
+extern "C" {}
+
+#[panic_handler]
+#[lang = "panic_impl"]
+fn rust_begin_panic(_: &core::panic::PanicInfo) -> ! {
+    core::intrinsics::abort();
+}
+
+#[lang = "eh_personality"]
+extern "C" fn eh_personality() {}
+
+#[cfg(unix)]
+#[no_mangle]
+pub extern "C" fn _Unwind_Resume() {}

no-std/examples/serde.rs

@@ -0,0 +1,74 @@
+#![no_std]
+#![allow(internal_features)]
+#![feature(start, core_intrinsics, lang_items, link_cfg)]
+
+mod prelude;
+
+use musli::allocator::{Stack, StackBuffer};
+use musli::context::StackContext;
+use musli::{Decode, Encode};
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Serialize, Deserialize)]
+struct Serde {
+    field: u32,
+}
+
+#[derive(Debug, Encode, Decode)]
+struct Value<'a> {
+    name: &'a str,
+    age: u32,
+    #[musli(with = musli::serde)]
+    serde: Serde,
+}
+
+#[start]
+fn main(_argc: isize, _argv: *const *const u8) -> isize {
+    let mut buf = StackBuffer::<1024>::new();
+    let alloc = Stack::new(&mut buf);
+    let cx = StackContext::new(&alloc);
+
+    let encoding = musli::json::Encoding::new();
+
+    let mut buf = [0u8; 1024];
+
+    let value = Value {
+        name: "Aristotle",
+        age: 61,
+        serde: Serde { field: 42 },
+    };
+
+    let mut w = &mut buf[..];
+
+    let Ok(..) = encoding.encode_with(&cx, &mut w, &value) else {
+        for _error in cx.errors() {
+            // report error
+        }
+
+        return 1;
+    };
+
+    let written = 1024 - w.len();
+
+    let Ok(value): Result<Value, _> = encoding.from_slice_with(&cx, &buf[..written]) else {
+        for _error in cx.errors() {
+            // report error
+        }
+
+        return 2;
+    };
+
+    if value.name != "Aristotle" {
+        return 3;
+    }
+
+    if value.age != 61 {
+        return 4;
+    }
+
+    if value.serde.field != 42 {
+        return 5;
+    }
+
+    0
+}