Use custom hasher for Map (#857)

* Use blake2 instead of two_x

* Add v4

* Update to new v4 static

* Update json

* Revert

* Use hasher enum

* Fix metadata v4 test

* Fix metadata v4 test

* Fix versioned metadata

* refactor & clean

* Use consistent naming

* Make jsons consistent

* Add backward compat

* Fix tests

* Start working on type-storage

* Fix output

* Grumble

* Update to latest static

* Clean code

* Fix imports

* Remove useless imports

* Fix tests

* Use prettier output for toJSON in metadata

* Implement different hashers

* Remove generic storageKey

* Bump version

* Add backwards-compat

* Fix hashing function, use Twox128

* Grumbles

* Add tests

packages/rpc-core/src/index.ts

@@ -192,7 +192,7 @@ export default class Rpc implements RpcInterface {
       const key = params[0] as StorageKey;
       const type = key.outputType || 'Data';
       const Clazz = createClass(type);
-      const meta = key.meta || { default: undefined, modifier: { isOptional: true } };
+      const meta = key.meta || { fallback: undefined, modifier: { isOptional: true } };
 
       if (key.meta && key.meta.type.isMap && key.meta.type.asMap.isLinked) {
         // linked map
@@ -218,11 +218,11 @@ export default class Rpc implements RpcInterface {
         const { value } = (base as StorageChangeSet).changes.find((item) =>
           item.key.toHex() === hexKey
         ) || { value: null };
-        const meta = key.meta || { default: undefined, modifier: { isOptional: true } };
+        const meta = key.meta || { fallback: undefined, modifier: { isOptional: true } };
 
         if (!value) {
           // if we don't have a value, do not fill in the entry, it will be up to the
-        // caller to sort this out, either ignoring or having a cache for older values
+          // caller to sort this out, either ignoring or having a cache for older values
           result.push(undefined);
         } else {
           if (key.meta && key.meta.type.isMap && key.meta.type.asMap.isLinked) {
@@ -236,7 +236,7 @@ export default class Rpc implements RpcInterface {
             } else {
               // for `null` we fallback to the default value, or create an empty type,
               // otherwise we return the actual value as retrieved
-              result.push(new Clazz(value.unwrapOr(meta.default)));
+              result.push(new Clazz(value.unwrapOr(meta.fallback)));
             }
           }
         }