[feature] #2004: Forbid isize and usize from becoming IntoSchema.

Signed-off-by: Aleksandr Petrosyan <a-p-petrosyan@yandex.ru>

schema/Cargo.toml

@@ -12,3 +12,6 @@ fixnum = { version = "0.6.1", default-features = false, features = ["i64"] }
 
 [dev-dependencies]
 parity-scale-codec = { version = "2.3.1", default-features = false, features = ["derive", "full"] }
+impls = { version = "=1.0.0" }
+
+iroha_schema_gen = { version = "=2.0.0-pre-rc.4", path = "gen" }

schema/tests/architecture-dependent.rs

@@ -0,0 +1,24 @@
+use impls::impls;
+use iroha_schema::IntoSchema;
+use parity_scale_codec::{Decode, Encode};
+
+#[test]
+fn usize_isize_not_into_schema() {
+    // The architecture-dependent
+    assert!(!impls!(usize: IntoSchema));
+    assert!(!impls!(isize: IntoSchema));
+
+    // use serde::Serialize;
+    //
+    // assert!(!impls!(usize: Serialize));
+    // `usize` should be `Serialize`.
+
+    // But not `Encode`/`Decode`.
+    assert!(!impls!(usize: Encode | Decode));
+    assert!(!impls!(isize: Encode | Decode));
+
+    // There are no other primitive architecture-dependent types, so
+    // as long as `IntoSchema` requires all variants and all fields to
+    // also be `IntoSchema`, we are guaranteed that all schema types
+    // are safe to exchange.
+}