add optional smol_str support (#72)

Co-authored-by: Graham Esau <gesau@hotmail.co.uk>

schemars/Cargo.toml

@@ -31,6 +31,7 @@ bytes = { version = "1.0", optional = true }
 rust_decimal = { version = "1", default-features = false, optional = true }
 bigdecimal = { version = "0.3", default-features = false, optional = true }
 enumset = { version = "1.0", optional = true }
+smol_str = { version = "0.1.17", optional = true }
 
 [dev-dependencies]
 pretty_assertions = "1.2.1"
@@ -102,5 +103,9 @@ required-features = ["url"]
 name = "enumset"
 required-features = ["enumset"]
 
+[[test]]
+name = "smol_str"
+required-features = ["smol_str"]
+
 [package.metadata.docs.rs]
 all-features = true

schemars/src/json_schema_impls/mod.rs

@@ -64,6 +64,8 @@ mod sequences;
 mod serdejson;
 #[cfg(feature = "smallvec")]
 mod smallvec;
+#[cfg(feature = "smol_str")]
+mod smol_str;
 mod time;
 mod tuple;
 #[cfg(feature = "url")]

schemars/src/json_schema_impls/smol_str.rs

@@ -0,0 +1,6 @@
+use crate::gen::SchemaGenerator;
+use crate::schema::*;
+use crate::JsonSchema;
+use smol_str::SmolStr;
+
+forward_impl!(SmolStr => String);

schemars/tests/expected/smol_str.json

@@ -0,0 +1,5 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "String",
+  "type": "string"
+}

schemars/tests/smol_str.rs

@@ -0,0 +1,8 @@
+mod util;
+use smol_str::SmolStr;
+use util::*;
+
+#[test]
+fn smol_str() -> TestResult {
+    test_default_generated_schema::<SmolStr>("smol_str")
+}