Merge pull request #1992 from AlphaWallet/replace-unnecessary_-vars-with-proper-nil-checks

Refactor: replace `if let _ = <something>` with `if <something> != nil`

AlphaWallet/Core/Initializers/MigrationInitializer.swift

@@ -20,7 +20,7 @@ class MigrationInitializer: Initializer {
             if oldSchemaVersion < 2 {
                 //Fix bug created during multi-chain implementation. Where TokenObject instances are created from transfer Transaction instances, with the primaryKey as a empty string; so instead of updating an existing TokenObject, a duplicate TokenObject instead was created but with primaryKey empty
                 migration.enumerateObjects(ofType: TokenObject.className()) { oldObject, newObject in
-                    guard let _ = oldObject else { return }
+                    guard oldObject != nil else { return }
                     guard let newObject = newObject else { return }
                     if let primaryKey = newObject["primaryKey"] as? String, primaryKey.isEmpty {
                         migration.delete(newObject)
@@ -30,9 +30,9 @@ class MigrationInitializer: Initializer {
             }
             if oldSchemaVersion < 3 {
                 migration.enumerateObjects(ofType: Transaction.className()) { oldObject, newObject in
-                    guard let _ = oldObject else { return }
+                    guard oldObject != nil else { return }
                     guard let newObject = newObject else { return }
-                    newObject["isERC20Interaction"] = false 
+                    newObject["isERC20Interaction"] = false
                 }
             }
             if oldSchemaVersion < 4 {
@@ -55,7 +55,7 @@ class MigrationInitializer: Initializer {
             }
             if oldSchemaVersion < 6 {
                 migration.enumerateObjects(ofType: TokenObject.className()) { oldObject, newObject in
-                    guard let _ = oldObject else { return }
+                    guard oldObject != nil else { return }
                     guard let newObject = newObject else { return }
 
                     newObject["shouldDisplay"] = true

AlphaWallet/TokenScriptClient/Models/AssetAttribute.swift

@@ -102,7 +102,7 @@ struct AssetAttribute {
                   let eventContractName = ethereumEventElement["contract"],
                   let eventSourceContractElement = XMLHandler.getContractElementByName(contractName: eventContractName, fromRoot: root, xmlContext: xmlContext),
                   let asnModuleElement = XMLHandler.getAsnModuleElement(fromRoot: root, xmlContext: xmlContext, forTypeName: eventName),
-                  let _ = attribute["name"] {
+                  attribute["name"] != nil {
             originFound = Origin(forEthereumEventElement: ethereumEventElement, asnModuleElement: asnModuleElement, sourceContractElement: eventSourceContractElement, xmlContext: xmlContext)
         }
 

AlphaWallet/Transactions/Views/TransactionsEmptyView.swift

@@ -42,7 +42,7 @@ class TransactionsEmptyView: UIView {
         ].asStackView(axis: .vertical, spacing: 30, alignment: .center)
         stackView.translatesAutoresizingMaskIntoConstraints = false
 
-        if let _ = onRetry {
+        if onRetry != nil {
             stackView.addArrangedSubview(button)
         }
 

AlphaWallet/Transfer/ViewControllers/SendViewController.swift

@@ -454,7 +454,7 @@ extension SendViewController: AmountTextFieldDelegate {
         textField.statusLabel.text = viewModel.availableLabelText
         textField.availableTextHidden = viewModel.availableTextHidden
 
-        guard let _ = viewModel.validatedAmount(value: textField.ethCost, checkIfGreaterThenZero: false) else {
+        guard viewModel.validatedAmount(value: textField.ethCost, checkIfGreaterThenZero: false) != nil else {
             textField.errorState = .error
             return
         }

AlphaWallet/UI/EmptyView.swift

@@ -43,7 +43,7 @@ class EmptyView: UIView {
         ].asStackView(axis: .vertical, spacing: 30, alignment: .center)
         stackView.translatesAutoresizingMaskIntoConstraints = false
 
-        if let _ = onRetry {
+        if onRetry != nil {
             stackView.addArrangedSubview(button)
         }
 

AlphaWallet/UI/FloatLabelCell.swift

@@ -126,7 +126,7 @@ public class _FloatLabelCell<T>: Cell<T>, UITextFieldDelegate, TextFieldCell whe
 
     public func textFieldDidBeginEditing(_ textField: UITextField) {
         formViewController()?.beginEditing(of: self)
-        if let fieldRowConformance = row as? FormatterConformance, let _ = fieldRowConformance.formatter, fieldRowConformance.useFormatterOnDidBeginEditing ?? fieldRowConformance.useFormatterDuringInput {
+        if let fieldRowConformance = row as? FormatterConformance, fieldRowConformance.formatter != nil, fieldRowConformance.useFormatterOnDidBeginEditing ?? fieldRowConformance.useFormatterDuringInput {
             textField.text = displayValue(useFormatter: true)
         } else {
             textField.text = displayValue(useFormatter: false)

AlphaWallet/UI/Views/AmountTextField.swift

@@ -147,7 +147,7 @@ class AmountTextField: UIControl {
 
     var cryptoToDollarRate: Double? = nil {
         didSet {
-            if let _ = cryptoToDollarRate {
+            if cryptoToDollarRate != nil {
                 updateAlternatePricingDisplay()
             }
             updateFiatButtonTitle()