Feature/decimal (#541)

* use Decimal instead of parseFloat

* use Decimal

src/balancer/OceanPool.ts

@@ -5,6 +5,7 @@ import { Pool } from './Pool'
 import { EventData, Filter } from 'web3-eth-contract'
 import BigNumber from 'bignumber.js'
 import { SubscribablePromise, Logger, didNoZeroX, didPrefixed } from '../utils'
+import Decimal from 'decimal.js'
 
 declare type PoolTransactionType = 'swap' | 'join' | 'exit'
 
@@ -120,7 +121,7 @@ export class OceanPool extends Pool {
       this.dtAddress = dtAddress
       let txid
       const dtAllowance = await this.allowance(dtAddress, account, address)
-      if (parseFloat(dtAllowance) < parseFloat(dtAmount)) {
+      if (new Decimal(dtAllowance).lt(dtAmount)) {
         observer.next(PoolCreateProgressStep.ApprovingDatatoken)
         txid = await this.approve(
           account,
@@ -134,7 +135,7 @@ export class OceanPool extends Pool {
         }
       }
       const oceanAllowance = await this.allowance(this.oceanAddress, account, address)
-      if (parseFloat(oceanAllowance) < parseFloat(oceanAmount)) {
+      if (new Decimal(oceanAllowance).lt(oceanAmount)) {
         observer.next(PoolCreateProgressStep.ApprovingOcean)
         txid = await this.approve(
           account,

src/balancer/Pool.ts

@@ -6,6 +6,7 @@ import BigNumber from 'bignumber.js'
 import jsonpoolABI from '@oceanprotocol/contracts/artifacts/BPool.json'
 import defaultDatatokensABI from '@oceanprotocol/contracts/artifacts/DataTokenTemplate.json'
 import { PoolFactory } from './PoolFactory'
+import Decimal from 'decimal.js'
 
 const MaxUint256 =
   '115792089237316195423570985008687907853269984665640564039457584007913129639934'
@@ -1036,7 +1037,7 @@ export class Pool extends PoolFactory {
   ): Promise<string> {
     const pool = new this.web3.eth.Contract(this.poolABI, poolAddress)
     let amount = null
-    if (parseFloat(tokenAmountOut) >= parseFloat(tokenBalanceOut)) return null
+    if (new Decimal(tokenAmountOut).gte(tokenBalanceOut)) return null
     try {
       const result = await pool.methods
         .calcInGivenOut(

src/datatokens/Datatokens.ts

@@ -7,6 +7,7 @@ import { Logger, getFairGasPrice } from '../utils'
 import wordListDefault from '../data/words.json'
 import { TransactionReceipt } from 'web3-core'
 import BigNumber from 'bignumber.js'
+import Decimal from 'decimal.js'
 
 /**
  * Provides an interface to DataTokens
@@ -174,7 +175,7 @@ export class DataTokens {
       from: address
     })
     const capAvailble = await this.getCap(dataTokenAddress)
-    if (parseFloat(capAvailble) >= parseFloat(amount)) {
+    if (new Decimal(capAvailble).gte(amount)) {
       const gasLimitDefault = this.GASLIMIT_DEFAULT
       let estGas
       try {