Versioning for #[runtime-interface] (#5328)

* versionned runtime-interface

* use only one additional wasm blob

* alter docs

* formatting, naming and docs

* add comment for test

* version duplicate err

* RuntimeInterfaceItem -> RuntimeInterfaceFunction<

* test naming

* version checking

* remove spaces

* Update primitives/runtime-interface/proc-macro/src/runtime_interface/bare_function_interface.rs

Co-Authored-By: Bastian Köcher <bkchr@users.noreply.github.com>

* remove sanity checks and reduce coverage

* add doc comment

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

substrate/primitives/runtime-interface/test-wasm/src/lib.rs

@@ -21,7 +21,7 @@
 use sp_runtime_interface::runtime_interface;
 
 #[cfg(not(feature = "std"))]
-use sp_std::{vec, vec::Vec, mem, convert::TryFrom};
+use sp_std::{prelude::*, mem, convert::TryFrom};
 
 use sp_core::{sr25519::Public, wasm_export_functions};
 
@@ -103,6 +103,15 @@ pub trait TestApi {
 	fn get_and_return_i128(val: i128) -> i128 {
 		val
 	}
+
+	fn test_versionning(&self, data: u32) -> bool {
+		data == 42 || data == 50
+	}
+
+	#[version(2)]
+	fn test_versionning(&self, data: u32) -> bool {
+		data == 42
+	}
 }
 
 /// This function is not used, but we require it for the compiler to include `sp-io`.
@@ -231,4 +240,14 @@ wasm_export_functions! {
 		}
 		assert_eq!(0, len);
 	}
+
+	fn test_versionning_works() {
+		// we fix new api to accept only 42 as a proper input
+		// as opposed to sp-runtime-interface-test-wasm-deprecated::test_api::verify_input
+		// which accepted 42 and 50.
+		assert!(test_api::test_versionning(42));
+
+		assert!(!test_api::test_versionning(50));
+		assert!(!test_api::test_versionning(102));
+	}
 }