Java2Swift: Back-tick escaping for Java method/field names that are Swift keywords

Author: DougGregor

Sources/Java2SwiftLib/JavaTranslator.swift

@@ -429,20 +429,21 @@ extension JavaTranslator {
     }
 
     let throwsStr = javaMethod.throwsCheckedException ? "throws" : ""
-
+    let swiftMethodName = javaMethod.getName().escapedSwiftName
     let methodAttribute: AttributeSyntax = javaMethod.isStatic ? "@JavaStaticMethod" : "@JavaMethod";
     return """
       \(methodAttribute)
-      public func \(raw: javaMethod.getName())\(raw: genericParameterClause)(\(raw: parametersStr))\(raw: throwsStr)\(raw: resultTypeStr)\(raw: whereClause)
+      public func \(raw: swiftMethodName)\(raw: genericParameterClause)(\(raw: parametersStr))\(raw: throwsStr)\(raw: resultTypeStr)\(raw: whereClause)
       """
   }
 
   package func translateField(_ javaField: Field) throws -> DeclSyntax {
     let typeName = try getSwiftTypeNameAsString(javaField.getGenericType()!, outerOptional: true)
     let fieldAttribute: AttributeSyntax = javaField.isStatic ? "@JavaStaticField" : "@JavaField";
+    let swiftFieldName = javaField.getName().escapedSwiftName
     return """
       \(fieldAttribute)
-      public var \(raw: javaField.getName()): \(raw: typeName)
+      public var \(raw: swiftFieldName): \(raw: typeName)
       """
   }
 

Sources/Java2SwiftLib/StringExtras.swift

@@ -11,6 +11,7 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 //===----------------------------------------------------------------------===//
+import SwiftParser
 
 extension String {
   /// Split the Swift type name into parent type + innermost type name.
@@ -24,4 +25,13 @@ extension String {
       name: String(suffix(from: index(after: lastDot)))
     )
   }
+
+  /// Escape a name with backticks if it's a Swift keyword.
+  var escapedSwiftName: String {
+    if isValidSwiftIdentifier(for: .variableName) {
+      return self
+    }
+
+    return "`\(self)`"
+  }
 }