Add schemars support

.github/workflows/rust.yml

@@ -11,7 +11,7 @@ jobs:
       matrix:
         os: [ubuntu-latest]
         rust:
-        - 1.55.0 # approximate MSRV is Stable -30
+        - 1.60.0 # approximate MSRV is Stable -30
         - stable
         - beta
         - nightly
@@ -28,11 +28,11 @@ jobs:
         toolchain: ${{ matrix.rust }}
     # On MSRV some dev-dependencies don't build so we can't run tests.
     - name: Check MSRV
-      if: matrix.rust == '1.55.0'
+      if: matrix.rust == '1.60.0'
       run: |
         cargo check --features=alloc,std,grab_spare_slice
     - name: Test non nightly
-      if: matrix.rust != '1.55.0' && matrix.rust != 'nightly'
+      if: matrix.rust != '1.60.0' && matrix.rust != 'nightly'
       run: |
         cargo test --features=alloc,std,grab_spare_slice,latest_stable_rust
     - name: Test on Nightly with All Features

Cargo.toml

@@ -20,6 +20,8 @@ arbitrary = { version = "1", optional = true }
 borsh = { version = "1.2.0", optional = true, default-features = false }
 # Implements the trait `Array` for `GenericArray` struct.
 generic-array = { version = "1.1.1", optional = true, default-features = false }
+# Provides `JsonSchema` implementations
+schemars = { version = "1.0", optional = true, default-features = false }
 
 
 [features]
@@ -75,12 +77,14 @@ experimental_write_impl = []
 # and thus a nightly compiler, but is only used in benchmarks.
 real_blackbox = ["criterion/real_blackbox"]
 
+schemars = ["dep:schemars", "alloc"]
+
 [package.metadata.docs.rs]
-features = ["alloc", "std", "grab_spare_slice", "latest_stable_rust", "serde", "borsh"]
+features = ["alloc", "std", "grab_spare_slice", "latest_stable_rust", "serde", "borsh", "schemars"]
 rustdoc-args = ["--cfg","docs_rs"]
 
 [package.metadata.playground]
-features = ["alloc", "std", "grab_spare_slice", "latest_stable_rust", "serde", "borsh"]
+features = ["alloc", "std", "grab_spare_slice", "latest_stable_rust", "serde", "borsh", "schemars"]
 
 [profile.bench]
 debug = 2

src/arrayvec.rs

@@ -287,6 +287,33 @@ where
   }
 }
 
+#[cfg(feature = "schemars")]
+#[cfg_attr(docs_rs, doc(cfg(feature = "schemars")))]
+impl<A> schemars::JsonSchema for ArrayVec<A>
+where
+  A: Array,
+  <A as Array>::Item: schemars::JsonSchema,
+{
+  fn schema_name() -> alloc::borrow::Cow<'static, str> {
+    alloc::format!(
+      "Array_up_to_size_{}_of_{}",
+      A::CAPACITY,
+      <A as Array>::Item::schema_name()
+    )
+    .into()
+  }
+
+  fn json_schema(
+    generator: &mut schemars::SchemaGenerator,
+  ) -> schemars::Schema {
+    schemars::json_schema!({
+        "type": "array",
+        "items": generator.subschema_for::<<A as Array>::Item>(),
+        "maxItems": A::CAPACITY
+    })
+  }
+}
+
 impl<A: Array> ArrayVec<A> {
   /// Move all values from `other` into this vec.
   ///

src/lib.rs

@@ -52,6 +52,8 @@
 //! * `borsh` provides a `BorshSerialize` and `BorshDeserialize` implementation
 //!   for [`TinyVec`] and [`ArrayVec`] types, provided the inner item also has
 //!   an implementation.
+//! * `schemars` provides a `JsonSchema` implementation for [`TinyVec`] and
+//!   [`ArrayVec`] types, provided the inner item also has an implementation.
 //!
 //! ## API
 //! The general goal of the crate is that, as much as possible, the vecs here

src/tinyvec.rs

@@ -273,6 +273,33 @@ where
   }
 }
 
+#[cfg(feature = "schemars")]
+#[cfg_attr(docs_rs, doc(cfg(feature = "schemars")))]
+impl<A> schemars::JsonSchema for TinyVec<A>
+where
+  A: Array,
+  <A as Array>::Item: schemars::JsonSchema,
+{
+  fn schema_name() -> alloc::borrow::Cow<'static, str> {
+    alloc::format!(
+      "Array_up_to_size_{}_of_{}",
+      A::CAPACITY,
+      <A as Array>::Item::schema_name()
+    )
+    .into()
+  }
+
+  fn json_schema(
+    generator: &mut schemars::SchemaGenerator,
+  ) -> schemars::Schema {
+    schemars::json_schema!({
+        "type": "array",
+        "items": generator.subschema_for::<<A as Array>::Item>(),
+        "maxItems": A::CAPACITY
+    })
+  }
+}
+
 impl<A: Array> TinyVec<A> {
   /// Returns whether elements are on heap
   #[inline(always)]