Implement sval2 support

Cargo.toml

@@ -20,6 +20,7 @@ arbitrary = { version = "1.0", optional = true, default-features = false }
 quickcheck = { version = "1.0", optional = true, default-features = false }
 serde = { version = "1.0", optional = true, default-features = false }
 rayon = { version = "1.9", optional = true }
+sval = { version = "2", optional = true, default-features = false }
 
 # deprecated: use borsh's "indexmap" feature instead.
 borsh = { version = "1.2", optional = true, default-features = false }
@@ -51,11 +52,11 @@ sign-tag = true
 tag-name = "{{version}}"
 
 [package.metadata.docs.rs]
-features = ["arbitrary", "quickcheck", "serde", "borsh", "rayon"]
+features = ["arbitrary", "quickcheck", "serde", "borsh", "rayon", "sval"]
 rustdoc-args = ["--cfg", "docsrs"]
 
 [workspace]
-members = ["test-nostd", "test-serde"]
+members = ["test-nostd", "test-serde", "test-sval"]
 
 [lints.clippy]
 style = "allow"

src/lib.rs

@@ -115,6 +115,8 @@ mod macros;
 mod borsh;
 #[cfg(feature = "serde")]
 mod serde;
+#[cfg(feature = "sval")]
+mod sval;
 mod util;
 
 pub mod map;

src/sval.rs

@@ -0,0 +1,36 @@
+#![cfg_attr(docsrs, doc(cfg(feature = "serde")))]
+
+use crate::{IndexMap, IndexSet};
+use sval::{Stream, Value};
+
+impl<K: Value, V: Value, S> Value for IndexMap<K, V, S> {
+    fn stream<'sval, ST: Stream<'sval> + ?Sized>(&'sval self, stream: &mut ST) -> sval::Result {
+        stream.map_begin(Some(self.len()))?;
+
+        for (k, v) in self {
+            stream.map_key_begin()?;
+            stream.value(k)?;
+            stream.map_key_end()?;
+
+            stream.map_value_begin()?;
+            stream.value(v)?;
+            stream.map_value_end()?;
+        }
+
+        stream.map_end()
+    }
+}
+
+impl<K: Value, S> Value for IndexSet<K, S> {
+    fn stream<'sval, ST: Stream<'sval> + ?Sized>(&'sval self, stream: &mut ST) -> sval::Result {
+        stream.seq_begin(Some(self.len()))?;
+
+        for value in self {
+            stream.seq_value_begin()?;
+            stream.value(value)?;
+            stream.seq_value_end()?;
+        }
+
+        stream.seq_end()
+    }
+}

test-sval/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "test-sval"
+version = "0.1.0"
+publish = false
+edition = "2021"
+
+[dependencies]
+
+[dev-dependencies]
+fnv = "1.0"
+indexmap = { path = "..", features = ["sval"] }
+sval = { version = "2", features = ["derive"] }
+sval_test = "2"

test-sval/src/lib.rs

@@ -0,0 +1,104 @@
+#![cfg(test)]
+
+use fnv::FnvBuildHasher;
+use indexmap::{indexmap, indexset, IndexMap, IndexSet};
+use sval_test::{assert_tokens, Token};
+
+#[test]
+fn test_sval_map() {
+    let map = indexmap! { 1 => 2, 3 => 4 };
+    assert_tokens(
+        &map,
+        &[
+            Token::MapBegin(Some(2)),
+            Token::MapKeyBegin,
+            Token::I32(1),
+            Token::MapKeyEnd,
+            Token::MapValueBegin,
+            Token::I32(2),
+            Token::MapValueEnd,
+            Token::MapKeyBegin,
+            Token::I32(3),
+            Token::MapKeyEnd,
+            Token::MapValueBegin,
+            Token::I32(4),
+            Token::MapValueEnd,
+            Token::MapEnd,
+        ],
+    );
+}
+
+#[test]
+fn test_sval_set() {
+    let set = indexset! { 1, 2, 3, 4 };
+    assert_tokens(
+        &set,
+        &[
+            Token::SeqBegin(Some(4)),
+            Token::SeqValueBegin,
+            Token::I32(1),
+            Token::SeqValueEnd,
+            Token::SeqValueBegin,
+            Token::I32(2),
+            Token::SeqValueEnd,
+            Token::SeqValueBegin,
+            Token::I32(3),
+            Token::SeqValueEnd,
+            Token::SeqValueBegin,
+            Token::I32(4),
+            Token::SeqValueEnd,
+            Token::SeqEnd,
+        ],
+    );
+}
+
+#[test]
+fn test_sval_map_fnv_hasher() {
+    let mut map: IndexMap<i32, i32, FnvBuildHasher> = Default::default();
+    map.insert(1, 2);
+    map.insert(3, 4);
+    assert_tokens(
+        &map,
+        &[
+            Token::MapBegin(Some(2)),
+            Token::MapKeyBegin,
+            Token::I32(1),
+            Token::MapKeyEnd,
+            Token::MapValueBegin,
+            Token::I32(2),
+            Token::MapValueEnd,
+            Token::MapKeyBegin,
+            Token::I32(3),
+            Token::MapKeyEnd,
+            Token::MapValueBegin,
+            Token::I32(4),
+            Token::MapValueEnd,
+            Token::MapEnd,
+        ],
+    );
+}
+
+#[test]
+fn test_sval_set_fnv_hasher() {
+    let mut set: IndexSet<i32, FnvBuildHasher> = Default::default();
+    set.extend(1..5);
+    assert_tokens(
+        &set,
+        &[
+            Token::SeqBegin(Some(4)),
+            Token::SeqValueBegin,
+            Token::I32(1),
+            Token::SeqValueEnd,
+            Token::SeqValueBegin,
+            Token::I32(2),
+            Token::SeqValueEnd,
+            Token::SeqValueBegin,
+            Token::I32(3),
+            Token::SeqValueEnd,
+            Token::SeqValueBegin,
+            Token::I32(4),
+            Token::SeqValueEnd,
+            Token::SeqEnd,
+        ],
+    );
+}