Fix no-param-reassign issues (#9235)

See [`no-param-reassign`](https://eslint.org/docs/rules/no-param-reassign) for more information.

This change enables `no-param-reassign` and fixes the issues raised by the rule.

.eslintrc.js

@@ -61,6 +61,7 @@ module.exports = {
     'no-loop-func': 'error',
     'no-negated-condition': 'error',
     'no-nested-ternary': 'error',
+    'no-param-reassign': 'error',
     'no-plusplus': ['error', { 'allowForLoopAfterthoughts': true }],
     'no-process-exit': 'error',
     'no-prototype-builtins': 'error',

app/scripts/controllers/network/network.js

@@ -101,8 +101,7 @@ export default class NetworkController extends EventEmitter {
     if (!type) {
       return
     }
-    network = networks.networkList[type]?.chainId || network
+    this.networkStore.putState(networks.networkList[type]?.chainId || network)
-    this.networkStore.putState(network)
   }
 
   isNetworkLoading () {

app/scripts/controllers/preferences.js

@@ -689,6 +689,7 @@ export default class PreferencesController {
   _getTokenRelatedStates (selectedAddress) {
     const accountTokens = this.store.getState().accountTokens
     if (!selectedAddress) {
+      // eslint-disable-next-line no-param-reassign
       selectedAddress = this.store.getState().selectedAddress
     }
     const providerType = this.network.providerStore.getState().type

app/scripts/controllers/transactions/index.js

@@ -271,6 +271,7 @@ export default class TransactionController extends EventEmitter {
     const defaultGasPrice = await this._getDefaultGasPrice(txMeta)
     const { gasLimit: defaultGasLimit, simulationFails } = await this._getDefaultGasLimit(txMeta, getCodeResponse)
 
+    // eslint-disable-next-line no-param-reassign
     txMeta = this.txStateManager.getTx(txMeta.id)
     if (simulationFails) {
       txMeta.simulationFails = simulationFails

app/scripts/controllers/transactions/tx-state-manager.js

@@ -262,6 +262,7 @@ export default class TransactionStateManager extends EventEmitter {
     if (typeof txParams.data === 'undefined') {
       delete txParams.data
     }
+    // eslint-disable-next-line no-param-reassign
     txParams = normalizeTxParams(txParams, false)
     this.validateTxParams(txParams)
     return txParams

app/scripts/lib/buy-eth-url.js

@@ -11,6 +11,7 @@
 export default function getBuyEthUrl ({ network, address, service }) {
   // default service by network if not specified
   if (!service) {
+    // eslint-disable-next-line no-param-reassign
     service = getDefaultServiceForNetwork(network)
   }
 

app/scripts/lib/migrator/index.js

@@ -46,6 +46,7 @@ export default class Migrator extends EventEmitter {
           throw new Error('Migrator - Migration did not update version number correctly')
         }
         // accept the migration as good
+        // eslint-disable-next-line no-param-reassign
         versionedData = migratedData
       } catch (err) {
         // rewrite error message to add context without clobbering stack

app/scripts/lib/setupSentry.js

@@ -122,13 +122,13 @@ export default function setupSentry ({ release, getState }) {
 function simplifyErrorMessages (report) {
   rewriteErrorMessages(report, (errorMessage) => {
     // simplify ethjs error messages
-    errorMessage = extractEthjsErrorMessage(errorMessage)
+    let simplifiedErrorMessage = extractEthjsErrorMessage(errorMessage)
     // simplify 'Transaction Failed: known transaction'
-    if (errorMessage.indexOf('Transaction Failed: known transaction') === 0) {
+    if (simplifiedErrorMessage.indexOf('Transaction Failed: known transaction') === 0) {
       // cut the hash from the error message
-      errorMessage = 'Transaction Failed: known transaction'
+      simplifiedErrorMessage = 'Transaction Failed: known transaction'
     }
-    return errorMessage
+    return simplifiedErrorMessage
   })
 }
 

app/scripts/migrations/038.js

@@ -19,17 +19,18 @@ function transformState (state) {
   const { ABTestController: ABTestControllerState = {} } = state
   const { abTests = {} } = ABTestControllerState
 
-  if (!abTests.fullScreenVsPopup) {
+  if (abTests.fullScreenVsPopup) {
-    state = {
+    return state
-      ...state,
+  }
-      ABTestController: {
+
-        ...ABTestControllerState,
+  return {
-        abTests: {
+    ...state,
-          ...abTests,
+    ABTestController: {
-          fullScreenVsPopup: 'control',
+      ...ABTestControllerState,
-        },
+      abTests: {
-      },
+        ...abTests,
-    }
+        fullScreenVsPopup: 'control',
+      },
+    },
   }
-  return state
 }

test/e2e/benchmark.js

@@ -92,17 +92,18 @@ async function isWritable (directory) {
 }
 
 async function getFirstParentDirectoryThatExists (directory) {
+  let nextDirectory = directory
   for (;;) {
     try {
-      await fs.access(directory, fsConstants.F_OK)
+      await fs.access(nextDirectory, fsConstants.F_OK)
-      return directory
+      return nextDirectory
     } catch (error) {
       if (error.code !== 'ENOENT') {
         throw error
-      } else if (directory === path.dirname(directory)) {
+      } else if (nextDirectory === path.dirname(nextDirectory)) {
         throw new Error('Failed to find parent directory that exists')
       }
-      directory = path.dirname(directory)
+      nextDirectory = path.dirname(nextDirectory)
     }
   }
 }

test/e2e/ganache.js

@@ -10,9 +10,8 @@ const defaultOptions = {
 }
 
 class Ganache {
-  async start (options) {
+  async start (opts) {
-    options = Object.assign({}, defaultOptions, options)
+    const options = { ...defaultOptions, ...opts }
-
     const port = options.port
     this._server = ganache.server(options)
 

test/e2e/webdriver/driver.js

@@ -136,9 +136,8 @@ class Driver {
   }
 
   async switchToWindowWithTitle (title, windowHandles) {
-    if (!windowHandles) {
+    // eslint-disable-next-line no-param-reassign
-      windowHandles = await this.driver.getAllWindowHandles()
+    windowHandles = windowHandles || await this.driver.getAllWindowHandles()
-    }
 
     for (const handle of windowHandles) {
       await this.driver.switchTo().window(handle)
@@ -158,6 +157,7 @@ class Driver {
    * @returns {Promise<void>}
    */
   async closeAllWindowHandlesExcept (exceptions, windowHandles) {
+    // eslint-disable-next-line no-param-reassign
     windowHandles = windowHandles || await this.driver.getAllWindowHandles()
 
     for (const handle of windowHandles) {

test/unit/app/controllers/permissions/mocks.js

@@ -108,6 +108,7 @@ export function getPermissionsMiddleware (permController, origin, extensionId) {
   return (req, res = {}, next = noop, end) => {
     return new Promise((resolve, reject) => {
 
+      // eslint-disable-next-line no-param-reassign
       end = end || _end
 
       middleware(req, res, next, end)

ui/app/components/app/signature-request-original/signature-request-original.component.js

@@ -247,6 +247,7 @@ export default class SignatureRequestOriginal extends Component {
           {
             rows.map(({ name, value }, index) => {
               if (typeof value === 'boolean') {
+                // eslint-disable-next-line no-param-reassign
                 value = value.toString()
               }
               return (

ui/app/components/ui/check-box/check-box.component.js

@@ -12,6 +12,7 @@ export const { CHECKED, INDETERMINATE, UNCHECKED } = CHECKBOX_STATE
 
 const CheckBox = ({ className, disabled, id, onClick, checked, title }) => {
   if (typeof checked === 'boolean') {
+    // eslint-disable-next-line no-param-reassign
     checked = checked
       ? CHECKBOX_STATE.CHECKED
       : CHECKBOX_STATE.UNCHECKED

ui/app/ducks/confirm-transaction/confirm-transaction.duck.js

@@ -258,16 +258,14 @@ export function setFetchingData (isFetching) {
 }
 
 export function updateGasAndCalculate ({ gasLimit, gasPrice }) {
-  gasLimit = addHexPrefix(gasLimit)
-  gasPrice = addHexPrefix(gasPrice)
   return (dispatch, getState) => {
     const { confirmTransaction: { txData } } = getState()
     const newTxData = {
       ...txData,
       txParams: {
         ...txData.txParams,
-        gas: gasLimit,
+        gas: addHexPrefix(gasLimit),
-        gasPrice,
+        gasPrice: addHexPrefix(gasPrice),
       },
     }
 

ui/app/ducks/gas/gas.duck.js

@@ -323,20 +323,22 @@ async function fetchExternalBasicGasAndTimeEstimates (dispatch) {
 }
 
 function extrapolateY ({ higherY, lowerY, higherX, lowerX, xForExtrapolation }) {
+  /* eslint-disable no-param-reassign */
   higherY = new BigNumber(higherY, 10)
   lowerY = new BigNumber(lowerY, 10)
   higherX = new BigNumber(higherX, 10)
   lowerX = new BigNumber(lowerX, 10)
   xForExtrapolation = new BigNumber(xForExtrapolation, 10)
+  /* eslint-enable no-param-reassign */
   const slope = (higherY.minus(lowerY)).div(higherX.minus(lowerX))
   const newTimeEstimate = slope.times(higherX.minus(xForExtrapolation)).minus(higherY).negated()
 
   return Number(newTimeEstimate.toPrecision(10))
 }
 
-function getRandomArbitrary (min, max) {
+function getRandomArbitrary (minStr, maxStr) {
-  min = new BigNumber(min, 10)
+  const min = new BigNumber(minStr, 10)
-  max = new BigNumber(max, 10)
+  const max = new BigNumber(maxStr, 10)
   const random = new BigNumber(String(Math.random()), 10)
   return new BigNumber(random.times(max.minus(min)).plus(min)).toPrecision(10)
 }

ui/app/helpers/utils/switch-direction.js

@@ -1,10 +1,11 @@
 /**
  * Switch the CSS stylesheet used between 'rtl' and 'ltr'
- * @param {('ltr' | 'rtl')} direction - Text direction, either left-to-right (ltr) or right-to-left (rtl)
+ * @param {('ltr' | 'rtl' | 'auto')} direction - Text direction, either left-to-right (ltr) or right-to-left (rtl)
  * @return {Promise<void>}
  */
 const switchDirection = async (direction) => {
   if (direction === 'auto') {
+    // eslint-disable-next-line no-param-reassign
     direction = 'ltr'
   }
   let updatedLink

ui/app/helpers/utils/util.js

@@ -241,6 +241,7 @@ export function getRandomFileName () {
 }
 
 export function exportAsFile (filename, data, type = 'text/csv') {
+  // eslint-disable-next-line no-param-reassign
   filename = filename || getRandomFileName()
   // source: https://stackoverflow.com/a/33542499 by Ludovic Feltz
   const blob = new window.Blob([data], { type })

ui/app/pages/send/send-content/add-recipient/ens-input.component.js

@@ -78,8 +78,8 @@ export default class EnsInput extends Component {
     updateEnsResolutionError('')
   }
 
-  lookupEnsName = (recipient) => {
+  lookupEnsName = (ensName) => {
-    recipient = recipient.trim()
+    const recipient = ensName.trim()
 
     log.info(`ENS attempting to resolve name: ${recipient}`)
     this.ens.lookup(recipient)

ui/app/pages/send/send.utils.js

@@ -238,6 +238,7 @@ async function estimateGas ({
 
   // if not, fall back to block gasLimit
   if (!blockGasLimit) {
+    // eslint-disable-next-line no-param-reassign
     blockGasLimit = MIN_GAS_LIMIT_HEX
   }
 

ui/app/pages/send/tests/send-utils.test.js

@@ -10,13 +10,14 @@ import {
 
 const stubs = {
   addCurrencies: sinon.stub().callsFake((a, b) => {
+    let [a1, b1] = [a, b]
     if (String(a).match(/^0x.+/u)) {
-      a = Number(String(a).slice(2))
+      a1 = Number(String(a).slice(2))
     }
     if (String(b).match(/^0x.+/u)) {
-      b = Number(String(b).slice(2))
+      b1 = Number(String(b).slice(2))
     }
-    return a + b
+    return a1 + b1
   }),
   conversionUtil: sinon.stub().callsFake((val) => parseInt(val, 16)),
   conversionGTE: sinon.stub().callsFake((obj1, obj2) => obj1.value >= obj2.value),

ui/app/store/actions.js

@@ -511,8 +511,7 @@ export function decryptMsgInline (decryptedMsgData) {
     }
 
     dispatch(updateMetamaskState(newState))
-    decryptedMsgData = newState.unapprovedDecryptMsgs[decryptedMsgData.metamaskId]
+    return newState.unapprovedDecryptMsgs[decryptedMsgData.metamaskId]
-    return decryptedMsgData
   }
 }