DAO-240: add multichain currency support (#120)

* add multichain currency support

src/defaults.js

@@ -1 +1,6 @@
 export const DEFAULT_ETH_NODE = 'wss://mainnet.eth.aragon.network/ws'
+export const DEFAULT_CURRENCY = {
+  name: 'Ether',
+  symbol: 'ETH',
+  decimals: 18
+}

src/evaluator/index.js

@@ -8,7 +8,7 @@ import Web3Utils from 'web3-utils'
 import BN from 'bn.js'
 import types from '../types'
 import HelperManager from '../helpers/HelperManager'
-import { DEFAULT_ETH_NODE } from '../defaults'
+import { DEFAULT_ETH_NODE, DEFAULT_CURRENCY } from '../defaults'
 
 /**
  * A value coupled with a type
@@ -54,14 +54,15 @@ class TypedValue {
  * @param {radspec/Bindings} bindings An object of bindings and their values
  * @param {?Object} options An options object
  * @param {?Object} options.availablehelpers Available helpers
+ * @param {?Object} options.currency Native currency of the blockchain
  * @param {?Web3} options.eth Web3 instance (used over options.ethNode)
  * @param {?string} options.ethNode The URL to an Ethereum node
  * @param {?string} options.to The destination address for this expression's transaction
  * @property {radspec/parser/AST} ast
  * @property {radspec/Bindings} bindings
  */
 export class Evaluator {
-  constructor (ast, bindings, { availableHelpers = {}, eth, ethNode, from, to, value = '0', data } = {}) {
+  constructor (ast, bindings, { availableHelpers = {}, eth, ethNode, from, to, value = '0', data, currency } = {}) {
     this.ast = ast
     this.bindings = bindings
     this.eth = eth || new Eth(ethNode || DEFAULT_ETH_NODE)
@@ -70,6 +71,7 @@ export class Evaluator {
     this.value = new TypedValue('uint', new BN(value))
     this.data = data && new TypedValue('bytes', data)
     this.helpers = new HelperManager(availableHelpers)
+    this.currency = currency || DEFAULT_CURRENCY
   }
 
   /**
@@ -358,6 +360,7 @@ export class Evaluator {
  * @param {?Object} options An options object
  * @param {?string} options.ethNode The URL to an Ethereum node
  * @param {?string} options.to The destination address for this expression's transaction
+ * @param {?Object} options.currency The native currency of the blockchain
  * @return {string}
  */
 export function evaluate (ast, bindings, options) {

src/helpers/lib/token.js

@@ -1,4 +1,5 @@
-export const ETH = '0x0000000000000000000000000000000000000000'
+export const NON_TOKEN_ADDRESS = '0x0000000000000000000000000000000000000000'
+export const ETH = NON_TOKEN_ADDRESS
 
 /* eslint-disable key-spacing, quotes */
 export const ERC20_SYMBOL_BYTES32_ABI = [

src/helpers/tokenAmount.js

@@ -1,9 +1,13 @@
 import BN from 'bn.js'
 import { toUtf8 } from 'web3-utils'
-import { ERC20_SYMBOL_BYTES32_ABI, ERC20_SYMBOL_DECIMALS_ABI, ETH } from './lib/token'
+import {
+  ERC20_SYMBOL_BYTES32_ABI,
+  ERC20_SYMBOL_DECIMALS_ABI,
+  NON_TOKEN_ADDRESS
+} from './lib/token'
 import { formatBN, tenPow } from './lib/formatBN'
 
-export default (eth) =>
+export default (eth, evaluator) =>
   /**
    * Format token amounts taking decimals into account
    *
@@ -20,10 +24,10 @@ export default (eth) =>
     let decimals
     let symbol
 
-    if (tokenAddress === ETH) {
-      decimals = new BN(18)
+    if (tokenAddress === NON_TOKEN_ADDRESS) {
+      decimals = new BN(evaluator.currency.decimals)
       if (showSymbol) {
-        symbol = 'ETH'
+        symbol = evaluator.currency.symbol
       }
     } else {
       let token = new eth.Contract(ERC20_SYMBOL_DECIMALS_ABI, tokenAddress)

src/index.js

@@ -53,6 +53,7 @@ import { evaluateRaw } from './lib'
  * @param {?Web3} options.eth Web3 instance (used over options.ethNode)
  * @param {?string} options.ethNode The URL to an Ethereum node
  * @param {?Object} options.userHelpers User defined helpers
+ * @param {?Object} options.currency Native currency of the blockchain
  * @return {Promise<string>} The result of the evaluation
  */
 function evaluate (source, call, { userHelpers = {}, ...options } = {}) {

test/examples/examples.js

@@ -166,9 +166,8 @@ const helperCases = [
     bindings: { token: address('0x89d24a6b4ccb1b6faa2625fe562bdd9a23260359'), balance: int('1000000000000000001') }
   }, 'Balance: 1.000000000000000001 DAI'],
   [{
-    source: 'Balance: `@tokenAmount(self.token(): address, balance)`',
-    bindings: { balance: int('10000000000000000000') },
-    options: { to: '0xD39902f046B5885D70e9E66594b65f84D4d1c952' }
+    source: 'Balance: `@tokenAmount(token, balance)`',
+    bindings: { balance: int('10000000000000000000'), token: address('0x960b236A07cf122663c4303350609A66A7B288C0') },
   }, 'Balance: 10 ANT'],
   [{
     source: 'Ethereum launched `@formatDate(date)`',
@@ -760,10 +759,10 @@ const cases = [
     options: { to: '0x960b236A07cf122663c4303350609A66A7B288C0' }
   }, 'Burns the ANT balance of 0x0000000000000000000000000000000000000001 (balance is 0)'],
   [{
-    source: 'Send ETH to the sale at block `((self.controller(): address).sale(): address).initialBlock(): uint` from `person`',
+    source: 'Send ETH to the sale at block `self.creationBlock(): uint` from `person`',
     bindings: { person: address('0x0000000000000000000000000000000000000001') },
     options: { to: '0x960b236A07cf122663c4303350609A66A7B288C0' }
-  }, 'Send ETH to the sale at block 3723000 from 0x0000000000000000000000000000000000000001'],
+  }, 'Send ETH to the sale at block 3711733 from 0x0000000000000000000000000000000000000001'],
   [{
     source: "Initialize Finance app for Vault at `_vault` with period length of `(_periodDuration - _periodDuration % 86400) / 86400` day`_periodDuration >= 172800 ? 's' : ' '`",
     bindings: { _periodDuration: int(86400 * 2), _vault: address('0x960b236A07cf122663c4303350609A66A7B288C0') }