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author | Dan Finlay <dan@danfinlay.com> | 2017-09-12 06:19:17 +0800 |
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committer | Dan Finlay <dan@danfinlay.com> | 2017-09-12 06:19:17 +0800 |
commit | 47387469680454c2df1211570bd924a7747cc628 (patch) | |
tree | 27dab1df20b1d15625b527a9964662bc88bacb39 | |
parent | 10b03cd6a225f6ada9fc5737a97b3adcb0708d96 (diff) | |
parent | d4d7c6d89eeddbe865e32b0f3636cc9de2a17cc1 (diff) | |
download | tangerine-wallet-browser-47387469680454c2df1211570bd924a7747cc628.tar.gz tangerine-wallet-browser-47387469680454c2df1211570bd924a7747cc628.tar.zst tangerine-wallet-browser-47387469680454c2df1211570bd924a7747cc628.zip |
Merge branch 'i1746-BalanceBasedOnPending' into AddBalanceController
-rw-r--r-- | app/scripts/lib/pending-balance-calculator.js | 51 | ||||
-rw-r--r-- | test/unit/pending-balance-test.js | 98 |
2 files changed, 149 insertions, 0 deletions
diff --git a/app/scripts/lib/pending-balance-calculator.js b/app/scripts/lib/pending-balance-calculator.js new file mode 100644 index 000000000..474ed3261 --- /dev/null +++ b/app/scripts/lib/pending-balance-calculator.js @@ -0,0 +1,51 @@ +const BN = require('ethereumjs-util').BN +const normalize = require('eth-sig-util').normalize + +class PendingBalanceCalculator { + + // Must be initialized with two functions: + // getBalance => Returns a promise of a BN of the current balance in Wei + // getPendingTransactions => Returns an array of TxMeta Objects, + // which have txParams properties, which include value, gasPrice, and gas, + // all in a base=16 hex format. + constructor ({ getBalance, getPendingTransactions }) { + this.getPendingTransactions = getPendingTransactions + this.getNetworkBalance = getBalance + } + + async getBalance() { + const results = await Promise.all([ + this.getNetworkBalance(), + this.getPendingTransactions(), + ]) + + const balance = results[0] + const pending = results[1] + + const pendingValue = pending.reduce((total, tx) => { + return total.add(this.valueFor(tx)) + }, new BN(0)) + + return `0x${balance.sub(pendingValue).toString(16)}` + } + + valueFor (tx) { + const txValue = tx.txParams.value + const value = this.hexToBn(txValue) + const gasPrice = this.hexToBn(tx.txParams.gasPrice) + + const gas = tx.txParams.gas + const gasLimit = tx.txParams.gasLimit + const gasLimitBn = this.hexToBn(gas || gasLimit) + + const gasCost = gasPrice.mul(gasLimitBn) + return value.add(gasCost) + } + + hexToBn (hex) { + return new BN(normalize(hex).substring(2), 16) + } + +} + +module.exports = PendingBalanceCalculator diff --git a/test/unit/pending-balance-test.js b/test/unit/pending-balance-test.js new file mode 100644 index 000000000..17be0306b --- /dev/null +++ b/test/unit/pending-balance-test.js @@ -0,0 +1,98 @@ +const assert = require('assert') +const PendingBalanceCalculator = require('../../app/scripts/lib/pending-balance-calculator') +const MockTxGen = require('../lib/mock-tx-gen') +const BN = require('ethereumjs-util').BN +let providerResultStub = {} + +const zeroBn = new BN(0) +const etherBn = new BN(String(1e18)) +const ether = '0x' + etherBn.toString(16) + +describe('PendingBalanceCalculator', function () { + let balanceCalculator + + describe('#valueFor(tx)', function () { + it('returns a BN for a given tx value', function () { + const txGen = new MockTxGen() + pendingTxs = txGen.generate({ + status: 'submitted', + txParams: { + value: ether, + gasPrice: '0x0', + gas: '0x0', + } + }, { count: 1 }) + + const balanceCalculator = generateBalanceCalcWith([], zeroBn) + const result = balanceCalculator.valueFor(pendingTxs[0]) + assert.equal(result.toString(), etherBn.toString(), 'computes one ether') + }) + + it('calculates gas costs as well', function () { + const txGen = new MockTxGen() + pendingTxs = txGen.generate({ + status: 'submitted', + txParams: { + value: '0x0', + gasPrice: '0x2', + gas: '0x3', + } + }, { count: 1 }) + + const balanceCalculator = generateBalanceCalcWith([], zeroBn) + const result = balanceCalculator.valueFor(pendingTxs[0]) + assert.equal(result.toString(), '6', 'computes one ether') + }) + }) + + describe('if you have no pending txs and one ether', function () { + + beforeEach(function () { + balanceCalculator = generateBalanceCalcWith([], etherBn) + }) + + it('returns the network balance', async function () { + const result = await balanceCalculator.getBalance() + assert.equal(result, ether, `gave ${result} needed ${ether}`) + }) + }) + + describe('if you have a one ether pending tx and one ether', function () { + beforeEach(function () { + const txGen = new MockTxGen() + pendingTxs = txGen.generate({ + status: 'submitted', + txParams: { + value: ether, + gasPrice: '0x0', + gas: '0x0', + } + }, { count: 1 }) + + balanceCalculator = generateBalanceCalcWith(pendingTxs, etherBn) + }) + + it('returns the subtracted result', async function () { + const result = await balanceCalculator.getBalance() + assert.equal(result, '0x0', `gave ${result} needed '0x0'`) + return true + }) + + }) +}) + +function generateBalanceCalcWith (transactions, providerStub = zeroBn) { + const getPendingTransactions = () => Promise.resolve(transactions) + const getBalance = () => Promise.resolve(providerStub) + providerResultStub.result = providerStub + const provider = { + sendAsync: (_, cb) => { cb(undefined, providerResultStub) }, + _blockTracker: { + getCurrentBlock: () => '0x11b568', + }, + } + return new PendingBalanceCalculator({ + getBalance, + getPendingTransactions, + }) +} |