fix: fix error handling in generateFaucetWallet (#1671)

* fix: handle error correctly in generateFaucetWallet
* test: Adds generateFaucetWallet integration + browser tests

test/integration/generateFaucetWallet.ts

@@ -0,0 +1,64 @@
+import assert from 'assert'
+
+import _ from 'lodash'
+
+import { Client, isValidClassicAddress, isValidXAddress } from 'xrpl-local'
+// how long before each test case times out
+const TIMEOUT = 60000
+// This test is reliant on external networks, and as such may be flaky.
+describe('generateFaucetWallet', function () {
+  this.timeout(TIMEOUT)
+
+  it('submit generates a testnet wallet', async function () {
+    const api = new Client('wss://s.altnet.rippletest.net:51233')
+
+    await api.connect()
+    const wallet = await api.generateFaucetWallet()
+
+    assert.notEqual(wallet, undefined)
+    assert(isValidClassicAddress(wallet?.classicAddress ?? ''))
+    assert(isValidXAddress(wallet?.getXAddress() ?? ''))
+
+    const info = await api.request({
+      command: 'account_info',
+      account: wallet?.classicAddress ?? '',
+    })
+    assert.equal(info.result.account_data.Balance, '1000000000')
+
+    await api.generateFaucetWallet(wallet)
+
+    const afterSent = await api.request({
+      command: 'account_info',
+      account: wallet?.classicAddress ?? '',
+    })
+    assert.equal(afterSent.result.account_data.Balance, '2000000000')
+
+    await api.disconnect()
+  })
+  it('submit generates a devnet wallet', async function () {
+    const api = new Client('wss://s.devnet.rippletest.net:51233')
+
+    await api.connect()
+    const wallet = await api.generateFaucetWallet()
+
+    assert.notEqual(wallet, undefined)
+    assert(isValidClassicAddress(wallet?.classicAddress ?? ''))
+    assert(isValidXAddress(wallet?.getXAddress() ?? ''))
+
+    const info = await api.request({
+      command: 'account_info',
+      account: wallet?.classicAddress ?? '',
+    })
+    assert.equal(info.result.account_data.Balance, '1000000000')
+
+    await api.generateFaucetWallet(wallet)
+
+    const afterSent = await api.request({
+      command: 'account_info',
+      account: wallet?.classicAddress ?? '',
+    })
+    assert.equal(afterSent.result.account_data.Balance, '2000000000')
+
+    await api.disconnect()
+  })
+})