feat(@mbark/ens): enable the use of $accounts in registrations

Enable putting `$accounts[i]` in subdomain registrations, where `i`
is the index of the `getAccounts` array.
This is the same behaviour we have for contract deployement

dapps/tests/app/test/namesystem_spec.js

@@ -4,14 +4,17 @@ const MyToken = require('Embark/contracts/MyToken');
 const MyToken2 = require('Embark/contracts/MyToken2');
 const EmbarkJS = require('Embark/EmbarkJS');
 
+let accounts;
+
 config({
   namesystem: {
     enabled: true,
     "register": {
       "rootDomain": "embark.eth",
       "subdomains": {
         "mytoken": "$MyToken",
-        "MyToken2": "$MyToken2"
+        "MyToken2": "$MyToken2",
+        "account": "$accounts[0]"
       }
     }
   },
@@ -30,15 +33,20 @@ config({
       }
     }
   }
+}, (_err, web3_accounts) => {
+  accounts = web3_accounts;
 });
 
 describe("ENS functions", function() {
   it('should allow directives in ENS subdomains', async function() {
     const myTokenAddress = await EmbarkJS.Names.resolve('mytoken.embark.eth');
-    assert.strictEqual(MyToken.options.address, myTokenAddress);
+    assert.strictEqual(myTokenAddress, MyToken.options.address);
 
     const myToken2Address = await EmbarkJS.Names.resolve('MyToken2.embark.eth');
-    assert.strictEqual(MyToken2.options.address, myToken2Address);
+    assert.strictEqual(myToken2Address, MyToken2.options.address);
+
+    const accountAddress = await EmbarkJS.Names.resolve('account.embark.eth');
+    assert.strictEqual(accountAddress, accounts[0]);
 
     const myTokenName = await EmbarkJS.Names.lookup(MyToken.options.address.toLowerCase());
     assert.strictEqual(myTokenName, 'mytoken.embark.eth');

packages/plugins/ens/src/index.js

@@ -181,20 +181,35 @@ class ENS {
   }
 
   async registerConfigDomains(config, cb) {
-    const defaultAccount = await this.web3DefaultAccount;
     if (!this.config.namesystemConfig.register) {
       return cb();
     }
+    const defaultAccount = await this.web3DefaultAccount;
+    const web3 = await this.web3;
 
     async.each(Object.keys(this.config.namesystemConfig.register.subdomains), (subDomainName, eachCb) => {
-      const address = this.config.namesystemConfig.register.subdomains[subDomainName];
+      let address = this.config.namesystemConfig.register.subdomains[subDomainName];
       const directivesRegExp = new RegExp(/\$(\w+\[?\d?\]?)/g);
 
-      const directives = directivesRegExp.exec(address);
-      if (directives && directives.length) {
-        return eachCb();
-      }
-      this.safeRegisterSubDomain(subDomainName, address, defaultAccount, eachCb);
+      // Using an anonymous function here because setting an async.js function as `async` creates issues
+      (async () => {
+        const directives = directivesRegExp.exec(address);
+        if (directives && directives.length) {
+          if (!directives[0].includes('accounts')) {
+            return eachCb();
+          }
+
+          const match = address.match(/\$accounts\[([0-9]+)]/);
+          const accountIndex = match[1];
+          const accounts = await web3.eth.getAccounts();
+
+          if (!accounts[accountIndex]) {
+            return eachCb(__('No corresponding account at index %d', match[1]));
+          }
+          address = accounts[accountIndex];
+        }
+        this.safeRegisterSubDomain(subDomainName, address, defaultAccount, eachCb);
+      })();
     }, cb);
   }
 
@@ -215,7 +230,7 @@ class ENS {
         const directivesRegExp = new RegExp(/\$(\w+\[?\d?\]?)/g);
 
         const directives = directivesRegExp.exec(address);
-        if (!directives || !directives.length) {
+        if (!directives || !directives.length || directives[0].includes('accounts')) {
           return resolve();
         }