Use util/assert (#30)

packages/api-provider/src/http/index.js

@@ -5,6 +5,7 @@ import type { ProviderInterface } from '../types';
 
 require('./polyfill');
 
+const assert = require('@polkadot/util/assert');
 const JsonRpcCoder = require('../jsonRpcCoder');
 
 module.exports = class HttpProvider extends JsonRpcCoder implements ProviderInterface {
@@ -28,9 +29,7 @@ module.exports = class HttpProvider extends JsonRpcCoder implements ProviderInte
       method: 'POST'
     });
 
-    if (!response.ok) {
-      throw new Error(`[${response.status}]: ${response.statusText}`);
-    }
+    assert(response.ok, `[${response.status}]: ${response.statusText}`);
 
     const result = await response.json();
 

packages/api-provider/src/jsonRpcCoder.js

@@ -3,33 +3,26 @@
 
 import type { JsonRpcRequest, JsonRpcResponse } from './types';
 
-const { isNumber, isUndefined } = require('@polkadot/util/is');
+const assert = require('@polkadot/util/assert');
+const isNumber = require('@polkadot/util/is/number');
+const isUndefined = require('@polkadot/util/is/undefined');
 
 module.exports = class JsonRpcCoder {
   _id: number = 0;
 
   decodeResponse (response: JsonRpcResponse): any {
-    if (!response) {
-      throw new Error('Empty response object received');
-    }
+    assert(response, 'Empty response object received');
 
-    if (response.jsonrpc !== '2.0') {
-      throw new Error('Invalid jsonrpc field in decoded object');
-    }
+    assert(response.jsonrpc === '2.0', 'Invalid jsonrpc field in decoded object');
 
-    if (!isNumber(response.id)) {
-      throw new Error('Invalid id field in decoded object');
-    }
+    assert(isNumber(response.id), 'Invalid id field in decoded object');
 
     if (response.error) {
       const { code, message } = response.error;
 
       throw new Error(`[${code}]: ${message}`);
     }
-
-    if (isUndefined(response.result)) {
-      throw new Error('No result found in JsonRpc response');
-    }
+    assert(!isUndefined(response.result), 'No result found in JsonRpc response');
 
     return response.result;
   }