BridgeJS: Escape reserved words

Author: wfltaylor

Plugins/BridgeJS/Sources/BridgeJSCore/ExportSwift.swift

@@ -216,7 +216,7 @@ public class ExportSwift {
             let liftingInfo = try param.type.liftParameterInfo()
             let argumentsToLift: [String]
             if liftingInfo.parameters.count == 1 {
-                argumentsToLift = [param.name]
+                argumentsToLift = [param.escapedSwiftIdentifier]
             } else {
                 argumentsToLift = liftingInfo.parameters.map { (name, _) in param.name + name.capitalizedFirstLetter }
             }
@@ -227,7 +227,9 @@ public class ExportSwift {
             switch param.type {
             case .closure(let signature, _):
                 typeNameForIntrinsic = param.type.swiftType
-                liftingExpr = ExprSyntax("_BJS_Closure_\(raw: signature.mangleName).bridgeJSLift(\(raw: param.name))")
+                liftingExpr = ExprSyntax(
+                    "_BJS_Closure_\(raw: signature.mangleName).bridgeJSLift(\(raw: param.escapedSwiftIdentifier))"
+                )
             case .swiftStruct(let structName):
                 typeNameForIntrinsic = structName
                 liftingExpr = ExprSyntax("\(raw: structName).bridgeJSLiftParameter()")
@@ -252,7 +254,7 @@ public class ExportSwift {
                 )
             }
 
-            parameterBindings.insert("let \(raw: param.name) = \(liftingExpr)", at: 0)
+            parameterBindings.insert("let \(raw: param.escapedSwiftIdentifier) = \(liftingExpr)", at: 0)
             for (name, type) in zip(argumentsToLift, liftingInfo.parameters.map { $0.type }) {
                 abiParameterSignatures.append((name, type))
             }
@@ -268,14 +270,14 @@ public class ExportSwift {
         }
 
         private func removeFirstLiftedParameter() -> String {
-            return parameters.removeFirst().name
+            return parameters.removeFirst().escapedSwiftIdentifier
         }
 
         private func renderCallStatement(callee: ExprSyntax, returnType: BridgeType) -> CodeBlockItemSyntax {
             let labeledParams = parameters.map { param in
                 LabeledExprSyntax(
                     label: param.label,
-                    expression: DeclReferenceExprSyntax(baseName: .identifier(param.name))
+                    expression: DeclReferenceExprSyntax(baseName: .identifier(param.escapedSwiftIdentifier))
                 )
             }
             var callExpr: ExprSyntax =
@@ -1593,6 +1595,12 @@ struct ProtocolCodegen {
     }
 }
 
+extension Parameter {
+    fileprivate var escapedSwiftIdentifier: String {
+        name.backtickIfNeeded()
+    }
+}
+
 extension WasmCoreType {
     var swiftType: String {
         switch self {

Plugins/BridgeJS/Sources/BridgeJSLink/BridgeJSLink.swift

@@ -1758,7 +1758,7 @@ public struct BridgeJSLink {
                 loweringFragment.parameters.count == 1,
                 "Lowering fragment should have exactly one parameter to lower"
             )
-            let paramName = scope.variable(param.name)
+            let paramName = scope.variable(param.escapedJSIdentifier)
             let loweredValues = try loweringFragment.printCode([paramName], context)
             parameterForwardings.append(contentsOf: loweredValues)
         }
@@ -1950,7 +1950,7 @@ public struct BridgeJSLink {
         }
         let parameterSignatures = parameters.map { param in
             let optional = param.hasDefault ? "?" : ""
-            return "\(param.name)\(optional): \(resolveTypeScriptType(param.type))"
+            return "\(param.escapedJSIdentifier)\(optional): \(resolveTypeScriptType(param.type))"
         }
         return "(\(parameterSignatures.joined(separator: ", "))): \(returnTypeWithEffect)"
     }
@@ -2669,7 +2669,7 @@ extension BridgeJSLink {
             if let constructor = klass.constructor {
                 let paramSignatures = constructor.parameters.map { param in
                     let optional = param.hasDefault ? "?" : ""
-                    return "\(param.name)\(optional): \(resolveTypeScriptType(param.type))"
+                    return "\(param.escapedJSIdentifier)\(optional): \(resolveTypeScriptType(param.type))"
                 }
                 printer.write(
                     lines: renderJSDoc(documentation: constructor.documentation, parameters: constructor.parameters)
@@ -4321,9 +4321,9 @@ enum DefaultValueUtils {
         return parameters.map { param in
             if let defaultValue = param.defaultValue {
                 let defaultJs = format(defaultValue, as: .javascript, resolveTypeName: resolveTypeName)
-                return "\(param.name) = \(defaultJs)"
+                return "\(param.escapedJSIdentifier) = \(defaultJs)"
             }
-            return param.name
+            return param.escapedJSIdentifier
         }.joined(separator: ", ")
     }
 }
@@ -4348,11 +4348,11 @@ extension BridgeJSLink {
             }
             switch (docText, defaultValue) {
             case let (.some(text), .some(value)):
-                tagLines.append("@param \(parameter.name) \(text) (default: \(value))")
+                tagLines.append("@param \(parameter.escapedJSIdentifier) \(text) (default: \(value))")
             case let (.some(text), .none):
-                tagLines.append("@param \(parameter.name) \(text)")
+                tagLines.append("@param \(parameter.escapedJSIdentifier) \(text)")
             case let (.none, .some(value)):
-                tagLines.append("@param \(parameter.name) - Optional parameter (default: \(value))")
+                tagLines.append("@param \(parameter.escapedJSIdentifier) - Optional parameter (default: \(value))")
             case (.none, .none):
                 continue
             }
@@ -4477,6 +4477,21 @@ struct BridgeJSLinkError: Error {
     let message: String
 }
 
+extension Parameter {
+    // From: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Lexical_grammar#reserved_words
+    private static let javaScriptReservedWords: Set<String> = [
+        "break", "case", "catch", "class", "const", "continue", "debugger", "default", "delete", "do", "else",
+        "export", "extends", "false", "finally", "for", "function", "if", "import", "in", "instanceof", "new",
+        "null", "return", "super", "switch", "this", "throw", "true", "try", "typeof", "var", "void", "while",
+        "with", "let", "static", "yield", "await", "enum", "implements", "interface", "package", "private",
+        "protected", "public", "arguments", "eval",
+    ]
+
+    fileprivate var escapedJSIdentifier: String {
+        Self.javaScriptReservedWords.contains(name) ? "_\(name)" : name
+    }
+}
+
 extension ClosureSignature {
     fileprivate func renderTSFunctionType(renderType: (BridgeType) -> String) -> String {
         let renderedParameters = parameters.enumerated().map { index, parameter in

Plugins/BridgeJS/Tests/BridgeJSToolTests/Inputs/MacroSwift/ReservedWordParameters.swift

@@ -0,0 +1 @@
+@JS func check(extension: Int, break: Double, function: Bool, in: String) {}

Plugins/BridgeJS/Tests/BridgeJSToolTests/__Snapshots__/BridgeJSCodegenTests/ReservedWordParameters.json

@@ -0,0 +1,81 @@
+{
+  "exported" : {
+    "aliases" : [
+
+    ],
+    "classes" : [
+
+    ],
+    "enums" : [
+
+    ],
+    "exposeToGlobal" : false,
+    "functions" : [
+      {
+        "abiName" : "bjs_check",
+        "effects" : {
+          "isAsync" : false,
+          "isStatic" : false,
+          "isThrows" : false
+        },
+        "name" : "check",
+        "parameters" : [
+          {
+            "label" : "extension",
+            "name" : "extension",
+            "type" : {
+              "integer" : {
+                "_0" : {
+                  "isSigned" : true,
+                  "width" : "word"
+                }
+              }
+            }
+          },
+          {
+            "label" : "break",
+            "name" : "break",
+            "type" : {
+              "double" : {
+
+              }
+            }
+          },
+          {
+            "label" : "function",
+            "name" : "function",
+            "type" : {
+              "bool" : {
+
+              }
+            }
+          },
+          {
+            "label" : "in",
+            "name" : "in",
+            "type" : {
+              "string" : {
+
+              }
+            }
+          }
+        ],
+        "returnType" : {
+          "void" : {
+
+          }
+        }
+      }
+    ],
+    "protocols" : [
+
+    ],
+    "structs" : [
+
+    ]
+  },
+  "moduleName" : "TestModule",
+  "usedExternalModules" : [
+
+  ]
+}

Plugins/BridgeJS/Tests/BridgeJSToolTests/__Snapshots__/BridgeJSCodegenTests/ReservedWordParameters.swift

@@ -0,0 +1,13 @@
+@_expose(wasm, "bjs_check")
+@_cdecl("bjs_check")
+public func _bjs_check(_ `extension`: Int32, _ `break`: Float64, _ function: Int32, _ inBytes: Int32, _ inLength: Int32) -> Void {
+    #if arch(wasm32)
+    let `in` = String.bridgeJSLiftParameter(inBytes, inLength)
+    let function = Bool.bridgeJSLiftParameter(function)
+    let `break` = Double.bridgeJSLiftParameter(`break`)
+    let `extension` = Int.bridgeJSLiftParameter(`extension`)
+    check(extension: `extension`, break: `break`, function: function, in: `in`)
+    #else
+    fatalError("Only available on WebAssembly")
+    #endif
+}

Plugins/BridgeJS/Tests/BridgeJSToolTests/__Snapshots__/BridgeJSLinkTests/ReservedWordParameters.d.ts

@@ -0,0 +1,18 @@
+// NOTICE: This is auto-generated code by BridgeJS from JavaScriptKit,
+// DO NOT EDIT.
+//
+// To update this file, just rebuild your project or run
+// `swift package bridge-js`.
+
+export type Exports = {
+    check(extension: number, _break: number, _function: boolean, _in: string): void;
+}
+export type Imports = {
+}
+export function createInstantiator(options: {
+    imports: Imports;
+}, swift: any): Promise<{
+    addImports: (importObject: WebAssembly.Imports) => void;
+    setInstance: (instance: WebAssembly.Instance) => void;
+    createExports: (instance: WebAssembly.Instance) => Exports;
+}>;