From 993bc05892ac9ce04ae0d4e9fa0a1b9d9b92936f Mon Sep 17 00:00:00 2001
From: Jaco Greeff <jacogr@gmail.com>
Date: Mon, 17 Jun 2019 10:41:57 +0200
Subject: [PATCH] USize is now non-constructable (#1022)

* USize is now unconstructable

* usize CHANGELOG entry
---
 CHANGELOG.md                          |  1 +
 packages/types/src/index.spec.ts      |  5 +++--
 packages/types/src/primitive/USize.ts |  9 ++++++++-
 packages/types/src/rpc/Health.ts      | 10 +++++-----
 4 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 253ad74392..97c943789d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,7 @@
 # 0.82.0-beta.x
 
 - **Breaking change** The `ContractsAbi` type has been moved from `@polkadot/types` to `import { Abi } from '@polkadot/api-contract`. This paves the way for an enhanced contracts interface, instead of dealing with low-level API calls.
+- **Breaking change** `usize` is now a blacklisted type that will throw on construction. Since it is platform-specific, it creates incompatibilities between native (generally u64) and WASM (always u32) code. Use one of the `u32` or `u64` types explicitly.
 - Update with latest substrate 2.x types
 
 # 0.81.1
diff --git a/packages/types/src/index.spec.ts b/packages/types/src/index.spec.ts
index c7c0701e28..981042bdef 100644
--- a/packages/types/src/index.spec.ts
+++ b/packages/types/src/index.spec.ts
@@ -8,6 +8,7 @@ import { Constructor } from './types';
 import * as Classes from './index.types';
 
 const Types = Classes as { [index: string]: Constructor };
+const UNCONSTRUCTABLE = ['origin', 'usize'];
 
 describe('types', () => {
   describe('default creation', () => {
@@ -16,7 +17,7 @@ describe('types', () => {
         const constructFn = () =>
           new Types[name]();
 
-        if (name === 'Origin') {
+        if (UNCONSTRUCTABLE.includes(name.toLowerCase())) {
           expect(constructFn).toThrow();
         } else {
           expect(constructFn).not.toThrow();
@@ -33,7 +34,7 @@ describe('types', () => {
         const constructFn = () =>
           new Types[name](new Types.Bytes());
 
-        if (name === 'Origin') {
+        if (UNCONSTRUCTABLE.includes(name.toLowerCase())) {
           expect(constructFn).toThrow();
         } else {
           expect(constructFn).not.toThrow();
diff --git a/packages/types/src/primitive/USize.ts b/packages/types/src/primitive/USize.ts
index cf33a68d56..1b4acf74e6 100644
--- a/packages/types/src/primitive/USize.ts
+++ b/packages/types/src/primitive/USize.ts
@@ -8,9 +8,16 @@ import U32 from './U32';
  * @name USize
  * @description
  * A System default unsigned number, typically used in RPC to report non-consensus
- * data. It is a wrapper for [[U32]] as a WASM default (as generated by Rust bindings)
+ * data. It is a wrapper for [[U32]] as a WASM default (as generated by Rust bindings).
+ * It is not to be used, since it created consensus mismatches.
  */
 export default class USize extends U32 {
+  constructor (value?: any) {
+    super(value);
+
+    throw new Error('The `usize` type should not be used. Since it is platform-specific, it creates incompatibilities between native (generally u64) and WASM (always u32) code. Use one of the `u32` or `u64` types explicitly.');
+  }
+
   /**
    * @description Returns the base runtime type name for this instance
    */
diff --git a/packages/types/src/rpc/Health.ts b/packages/types/src/rpc/Health.ts
index 4992051321..19aa59db5e 100644
--- a/packages/types/src/rpc/Health.ts
+++ b/packages/types/src/rpc/Health.ts
@@ -4,7 +4,7 @@
 
 import Struct from '../codec/Struct';
 import Bool from '../primitive/Bool';
-import USize from '../primitive/USize';
+import U64 from '../primitive/U64';
 
 /**
  * @name Health
@@ -14,7 +14,7 @@ import USize from '../primitive/USize';
 export default class Health extends Struct {
   constructor (value?: any) {
     super({
-      peers: USize,
+      peers: U64,
       isSyncing: Bool,
       shouldHavePeers: Bool
     }, value);
@@ -28,10 +28,10 @@ export default class Health extends Struct {
   }
 
   /**
-   * @description The numbers of peers as [[U32]]
+   * @description The numbers of peers as [[U64]]
    */
-  get peers (): USize {
-    return this.get('peers') as USize;
+  get peers (): U64 {
+    return this.get('peers') as U64;
   }
 
   /**