fix: align reflected shapes with Serde behavior

Cargo.toml

@@ -39,11 +39,13 @@ serde-shape-derive = { version = "=0.0.1", path = "serde-shape-derive" }
 # crates.io dependencies
 clap = { version = "4.6.1" }
 insta = { version = "1.48.0" }
+proc-macro-crate = { version = "3.5.0" }
 proc-macro2 = { version = "1.0.95" }
 quote = { version = "1.0.40" }
 serde = { version = "1.0.229", features = ["derive"] }
 serde_derive_internals = { version = "0.29.1" }
 serde_json = { version = "1.0.151" }
+serde_test = { version = "1.0.177" }
 syn = { version = "2.0.104" }
 toml_edit = { version = "0.25.13", features = ["serde"] }
 which = { version = "8.0.4" }

README.md

@@ -105,6 +105,22 @@ See the [crate documentation][docs-url] for the full shape graph model, derive b
 - `derive`: enables `#[derive(SerializeShape)]` and `#[derive(DeserializeShape)]`.
 - `std`: enables shape implementations for standard-library-only types.
 
+## Built-in shapes
+
+The built-in implementations follow Serde's own data-model calls in each direction.
+
+| Group | Supported types |
+| --- | --- |
+| Scalars | Rust primitives, `String`, `str`, non-zero integers, and atomics available on the target |
+| Containers | `Option`, `Result`, arrays, slices for serialization, tuples through arity 16, `Vec`, `VecDeque`, `LinkedList`, `BinaryHeap`, `BTreeSet`, and `BTreeMap` |
+| Wrappers | References, `Box`, `Cow`, `Cell`, `RefCell`, `Wrapping`, `Reverse`, and `PhantomData` |
+| Time | `core::time::Duration` |
+| `std` feature | `HashMap`, `HashSet`, `Path`, `PathBuf`, IP and socket address types, `Mutex`, and `RwLock` |
+
+Network address shapes are unions of their human-readable string representation and their compact Serde representation. A serialized byte slice is a sequence, while borrowed byte deserialization uses `ShapeRef::Bytes`.
+
+For an unsupported foreign type, use a local newtype and implement `SerializeShape` or `DeserializeShape` manually. Custom Serde functions remain visible as opaque boundaries because their wire behavior cannot be inferred.
+
 ## `no_std` support
 
 `serde-shape` is `no_std` by default and requires `alloc`.

serde-shape-derive/Cargo.toml

@@ -32,6 +32,7 @@ rust-version.workspace = true
 proc-macro = true
 
 [dependencies]
+proc-macro-crate = { workspace = true }
 proc-macro2 = { workspace = true }
 quote = { workspace = true }
 serde_derive_internals = { workspace = true }