Backtick variable/method names that conflict with Swift keywords

.github/scripts/compile-snapshots.sh

@@ -9,5 +9,7 @@ for snapshot in Tests/XCStringsToolTests/__Snapshots__/**/*.swift; do
 
   if xcrun swiftc "$snapshot" -package-name "MyPackage" -o /dev/null ; then
     echo "  Success"
+  else
+    exit $?
   fi
 done

Sources/StringGenerator/Extensions/String+BacktickIfNeeded.swift

@@ -0,0 +1,45 @@
+import SwiftSyntax
+import SwiftParser
+
+extension String {
+    var backtickedVariableNameIfNeeded: String {
+        // In SwiftSyntax 600, use isValidIdentifier(for:)
+        // https://github.com/apple/swift-syntax/pull/2434
+        // Thanks @ahoppen!
+        _isValidVariableName ? self : "`\(self)`"
+    }
+
+    private var _isValidVariableName: Bool {
+        let name = self
+
+        var parser = Parser("var \(name)")
+        let decl = DeclSyntax.parse(from: &parser)
+
+        guard !decl.hasError && !decl.hasWarning else {
+            // There were syntax errors in the source code. So not valid.
+            return false
+        }
+
+        guard let variable = decl.as(VariableDeclSyntax.self) else {
+            return false
+        }
+
+        guard let identifier = variable.bindings.first?.pattern.as(IdentifierPatternSyntax.self)?.identifier else {
+            return false
+        }
+
+        guard case .identifier = identifier.tokenKind else {
+            // We parsed the name as a keyword, eg. `self`, so not a valid identifier.
+            return false
+        }
+
+        guard identifier.text.count == name.utf8.count else {
+            // The identifier doesn't cover all the characters in `name`, so we parsed
+            // some of these characters into trivia or another token.
+            // Thus, `name` is not a valid identifier.
+            return false
+        }
+
+        return true
+    }
+}

Sources/StringGenerator/Models/SourceFile_LocalizedStringResourceExtension_StringsTableStruct_ResourceAccessor.swift

@@ -10,7 +10,11 @@ extension SourceFile.LocalizedStringResourceExtension.StringsTableStruct {
             !resource.arguments.isEmpty
         }
 
-        var name: TokenSyntax {
+        var variableName: TokenSyntax {
+            .identifier(resource.identifier.backtickedVariableNameIfNeeded)
+        }
+
+        var nameForMemberAccess: TokenSyntax {
             .identifier(resource.identifier)
         }
 

Sources/StringGenerator/Models/SourceFile_StringExtension_StringsTableStruct_ResourceAccessor.swift

@@ -10,8 +10,8 @@ extension SourceFile.StringExtension.StringsTableStruct {
             !resource.arguments.isEmpty
         }
 
-        var name: TokenSyntax {
-            .identifier(resource.identifier)
+        var variableName: TokenSyntax {
+            .identifier(resource.identifier.backtickedVariableNameIfNeeded)
         }
 
         var type: TokenSyntax {

Sources/StringGenerator/Snippets/LocalizedStringResource/StringsTable/LocalizedStringResourceStringsTableResourceFunctionSnippet.swift

@@ -9,7 +9,7 @@ struct LocalizedStringResourceStringsTableResourceFunctionSnippet: Snippet {
             leadingTrivia: leadingTrivia,
             attributes: attributes.map({ $0.with(\.trailingTrivia, .newline) }),
             modifiers: modifiers,
-            name: accessor.name,
+            name: accessor.variableName,
             signature: FunctionSignatureSyntax(
                 parameterClause: FunctionParameterClauseSyntax {
                     for argument in accessor.resource.arguments {
@@ -57,7 +57,7 @@ struct LocalizedStringResourceStringsTableResourceFunctionSnippet: Snippet {
             LabeledExprSyntax(
                 label: accessor.sourceFile.tableVariableIdentifier,
                 expression: FunctionCallExprSyntax(
-                    callee: MemberAccessExprSyntax(name: accessor.name)
+                    callee: MemberAccessExprSyntax(name: accessor.nameForMemberAccess)
                 ) {
                     for argument in accessor.resource.arguments {
                         LabeledExprSyntax(

Sources/StringGenerator/Snippets/LocalizedStringResource/StringsTable/LocalizedStringResourceStringsTableResourceVariableSnippet.swift

@@ -12,7 +12,7 @@ struct LocalizedStringResourceStringsTableResourceVariableSnippet: Snippet {
             bindingSpecifier: .keyword(.var),
             bindings: [
                 PatternBindingSyntax(
-                    pattern: IdentifierPatternSyntax(identifier: accessor.name),
+                    pattern: IdentifierPatternSyntax(identifier: accessor.variableName),
                     typeAnnotation: TypeAnnotationSyntax(type: accessor.type),
                     accessorBlock: AccessorBlockSyntax(
                         accessors: .getter(getter)
@@ -56,7 +56,7 @@ struct LocalizedStringResourceStringsTableResourceVariableSnippet: Snippet {
         ) {
             LabeledExprSyntax(
                 label: accessor.sourceFile.tableVariableIdentifier,
-                expression: MemberAccessExprSyntax(name: accessor.name)
+                expression: MemberAccessExprSyntax(name: accessor.nameForMemberAccess)
             )
         }
     }

Sources/StringGenerator/Snippets/String/StringsTable/StringStringsTableResourceFunctionSnippet.swift

@@ -8,7 +8,7 @@ struct StringStringsTableResourceFunctionSnippet: Snippet {
         FunctionDeclSyntax(
             leadingTrivia: leadingTrivia,
             modifiers: modifiers,
-            name: accessor.name,
+            name: accessor.variableName,
             signature: FunctionSignatureSyntax(
                 parameterClause: FunctionParameterClauseSyntax {
                     for argument in accessor.resource.arguments {

Sources/StringGenerator/Snippets/String/StringsTable/StringStringsTableResourceVariableSnippet.swift

@@ -11,7 +11,7 @@ struct StringStringsTableResourceVariableSnippet: Snippet {
             bindingSpecifier: .keyword(.var),
             bindings: [
                 PatternBindingSyntax(
-                    pattern: IdentifierPatternSyntax(identifier: accessor.name),
+                    pattern: IdentifierPatternSyntax(identifier: accessor.variableName),
                     typeAnnotation: TypeAnnotationSyntax(type: IdentifierTypeSyntax(name: accessor.type)),
                     accessorBlock: AccessorBlockSyntax(
                         accessors: .getter(getter)

Tests/XCStringsToolTests/__Fixtures__/Localizable.xcstrings

@@ -1,6 +1,18 @@
 {
   "sourceLanguage" : "en",
   "strings" : {
+    "continue" : {
+      "comment" : "A key that conflicts with a keyword in swift that isn't suitable for a variable/method and should be backticked.",
+      "extractionState" : "manual",
+      "localizations" : {
+        "en" : {
+          "stringUnit" : {
+            "state" : "translated",
+            "value" : "Continue"
+          }
+        }
+      }
+    },
     "Empty" : {
       "extractionState" : "manual"
     },

Tests/XCStringsToolTests/__Snapshots__/GenerateTests/testGenerate.Localizable.swift

@@ -17,15 +17,15 @@ extension String {
     ///
     /// ```swift
     /// // Accessing the localized value directly
-    /// let value = String(localizable: .key)
-    /// value // "Default Value"
+    /// let value = String(localizable: .continue)
+    /// value // "Continue"
     /// ```
     ///
     /// Starting in iOS 16/macOS 13/tvOS 16/watchOS 9, `LocalizedStringResource` can also
     /// be used:
     ///
     /// ```swift
-    /// var resource = LocalizedStringResource(localizable: .key)
+    /// var resource = LocalizedStringResource(localizable: .continue)
     /// resource.locale = Locale(identifier: "fr") // customise language
     /// let value = String(localized: resource)    // defer lookup
     /// ```
@@ -107,6 +107,22 @@ extension String {
             self.bundle = bundle
         }
 
+        /// A key that conflicts with a keyword in swift that isn't suitable for a variable/method and should be backticked.
+        ///
+        /// ### Source Localization
+        ///
+        /// ```
+        /// Continue
+        /// ```
+        internal static var `continue`: Localizable {
+            Localizable(
+                key: "continue",
+                arguments: [],
+                table: "Localizable",
+                bundle: .current
+            )
+        }
+
         /// This is a comment
         ///
         /// ### Source Localization
@@ -236,15 +252,31 @@ extension LocalizedStringResource {
     ///
     /// ```swift
     /// // Accessing the localized value directly
-    /// let value = String(localized: .localizable.key)
-    /// value // "Default Value"
+    /// let value = String(localized: .localizable.continue)
+    /// value // "Continue"
     ///
     /// // Working with SwiftUI
-    /// Text(.localizable.key)
+    /// Text(.localizable.continue)
     /// ```
     ///
     /// - Note: Using ``LocalizedStringResource.Localizable`` requires iOS 16/macOS 13 or later. See ``String.Localizable`` for a backwards compatible API.
     internal struct Localizable {
+        /// A key that conflicts with a keyword in swift that isn't suitable for a variable/method and should be backticked.
+        ///
+        /// ### Source Localization
+        ///
+        /// ```
+        /// Continue
+        /// ```
+        @available (iOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        @available (macOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        @available (tvOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        @available (watchOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        @available (visionOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        internal var `continue`: LocalizedStringResource {
+            LocalizedStringResource(localizable: .continue)
+        }
+
         /// This is a comment
         ///
         /// ### Source Localization

Tests/XCStringsToolTests/__Snapshots__/GenerateTests/testGenerateWithPackageAccessLevel.Localizable.swift

@@ -17,15 +17,15 @@ extension String {
     ///
     /// ```swift
     /// // Accessing the localized value directly
-    /// let value = String(localizable: .key)
-    /// value // "Default Value"
+    /// let value = String(localizable: .continue)
+    /// value // "Continue"
     /// ```
     ///
     /// Starting in iOS 16/macOS 13/tvOS 16/watchOS 9, `LocalizedStringResource` can also
     /// be used:
     ///
     /// ```swift
-    /// var resource = LocalizedStringResource(localizable: .key)
+    /// var resource = LocalizedStringResource(localizable: .continue)
     /// resource.locale = Locale(identifier: "fr") // customise language
     /// let value = String(localized: resource)    // defer lookup
     /// ```
@@ -107,6 +107,22 @@ extension String {
             self.bundle = bundle
         }
 
+        /// A key that conflicts with a keyword in swift that isn't suitable for a variable/method and should be backticked.
+        ///
+        /// ### Source Localization
+        ///
+        /// ```
+        /// Continue
+        /// ```
+        package static var `continue`: Localizable {
+            Localizable(
+                key: "continue",
+                arguments: [],
+                table: "Localizable",
+                bundle: .current
+            )
+        }
+
         /// This is a comment
         ///
         /// ### Source Localization
@@ -236,15 +252,31 @@ extension LocalizedStringResource {
     ///
     /// ```swift
     /// // Accessing the localized value directly
-    /// let value = String(localized: .localizable.key)
-    /// value // "Default Value"
+    /// let value = String(localized: .localizable.continue)
+    /// value // "Continue"
     ///
     /// // Working with SwiftUI
-    /// Text(.localizable.key)
+    /// Text(.localizable.continue)
     /// ```
     ///
     /// - Note: Using ``LocalizedStringResource.Localizable`` requires iOS 16/macOS 13 or later. See ``String.Localizable`` for a backwards compatible API.
     package struct Localizable {
+        /// A key that conflicts with a keyword in swift that isn't suitable for a variable/method and should be backticked.
+        ///
+        /// ### Source Localization
+        ///
+        /// ```
+        /// Continue
+        /// ```
+        @available (iOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        @available (macOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        @available (tvOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        @available (watchOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        @available (visionOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        package var `continue`: LocalizedStringResource {
+            LocalizedStringResource(localizable: .continue)
+        }
+
         /// This is a comment
         ///
         /// ### Source Localization

Tests/XCStringsToolTests/__Snapshots__/GenerateTests/testGenerateWithPublicAccessLevel.Localizable.swift

@@ -17,15 +17,15 @@ extension String {
     ///
     /// ```swift
     /// // Accessing the localized value directly
-    /// let value = String(localizable: .key)
-    /// value // "Default Value"
+    /// let value = String(localizable: .continue)
+    /// value // "Continue"
     /// ```
     ///
     /// Starting in iOS 16/macOS 13/tvOS 16/watchOS 9, `LocalizedStringResource` can also
     /// be used:
     ///
     /// ```swift
-    /// var resource = LocalizedStringResource(localizable: .key)
+    /// var resource = LocalizedStringResource(localizable: .continue)
     /// resource.locale = Locale(identifier: "fr") // customise language
     /// let value = String(localized: resource)    // defer lookup
     /// ```
@@ -107,6 +107,22 @@ extension String {
             self.bundle = bundle
         }
 
+        /// A key that conflicts with a keyword in swift that isn't suitable for a variable/method and should be backticked.
+        ///
+        /// ### Source Localization
+        ///
+        /// ```
+        /// Continue
+        /// ```
+        public static var `continue`: Localizable {
+            Localizable(
+                key: "continue",
+                arguments: [],
+                table: "Localizable",
+                bundle: .current
+            )
+        }
+
         /// This is a comment
         ///
         /// ### Source Localization
@@ -236,15 +252,31 @@ extension LocalizedStringResource {
     ///
     /// ```swift
     /// // Accessing the localized value directly
-    /// let value = String(localized: .localizable.key)
-    /// value // "Default Value"
+    /// let value = String(localized: .localizable.continue)
+    /// value // "Continue"
     ///
     /// // Working with SwiftUI
-    /// Text(.localizable.key)
+    /// Text(.localizable.continue)
     /// ```
     ///
     /// - Note: Using ``LocalizedStringResource.Localizable`` requires iOS 16/macOS 13 or later. See ``String.Localizable`` for a backwards compatible API.
     public struct Localizable {
+        /// A key that conflicts with a keyword in swift that isn't suitable for a variable/method and should be backticked.
+        ///
+        /// ### Source Localization
+        ///
+        /// ```
+        /// Continue
+        /// ```
+        @available (iOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        @available (macOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        @available (tvOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        @available (watchOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        @available (visionOS, deprecated: 100000, message: "Use `String.Localizable.continue` instead. This property will be removed in the future.")
+        public var `continue`: LocalizedStringResource {
+            LocalizedStringResource(localizable: .continue)
+        }
+
         /// This is a comment
         ///
         /// ### Source Localization