Merge pull request #820 from wfltaylor/async-throws-protocol

BridgeJS: Support exporting protocol methods with async and throws

Author: krodak

Plugins/BridgeJS/Sources/BridgeJSCore/ExportSwift.swift

@@ -1439,7 +1439,7 @@ struct ProtocolCodegen {
             let signature = SwiftSignatureBuilder.buildFunctionSignature(
                 parameters: method.parameters,
                 returnType: method.returnType,
-                effects: nil
+                effects: method.effects
             )
 
             // Build extern declaration using helper function

Plugins/BridgeJS/Sources/BridgeJSLink/BridgeJSLink.swift

@@ -2897,9 +2897,8 @@ extension BridgeJSLink {
 
         /// Renders an async import function with resolve/reject closure refs.
         ///
-        /// The generated function takes `resolveRef` and `rejectRef` as the first parameters,
-        /// looks up the resolve/reject closures from memory, and executes the body which
-        /// chains `.then(resolve, reject)` on the import's returned Promise.
+        /// The generated function takes `resolveRef` and `rejectRef` as the first parameters
+        /// and settles them with the result of the import call.
         private func renderAsyncFunction(name: String?) -> [String] {
             let printer = CodeFragmentPrinter()
             let allParams = ["resolveRef", "rejectRef"] + parameterNames
@@ -2908,7 +2907,15 @@ extension BridgeJSLink {
                 let s = JSGlueVariableScope.reservedSwift
                 printer.write("const resolve = \(s).memory.getObject(resolveRef);")
                 printer.write("const reject = \(s).memory.getObject(rejectRef);")
-                printer.write(contentsOf: body)
+                printer.write("try {")
+                printer.indent {
+                    printer.write(contentsOf: body)
+                }
+                printer.write("} catch (error) {")
+                printer.indent {
+                    printer.write("reject(error);")
+                }
+                printer.write("}")
             }
             printer.write("}")
             return printer.lines
@@ -2930,7 +2937,7 @@ extension BridgeJSLink {
 
         private func call(callExpr: String) throws {
             if effects.isAsync {
-                body.write("\(callExpr).then(resolve, reject);")
+                body.write("Promise.resolve(\(callExpr)).then(resolve, reject);")
                 return
             }
             if let name = returnType.referencedGenericName {
@@ -2997,14 +3004,6 @@ extension BridgeJSLink {
             return try call(calleeExpr: calleeExpr)
         }
 
-        /// Generates an async method call with resolve/reject closure refs.
-        func callAsyncMethod(name: String) {
-            let objectExpr = "\(JSGlueVariableScope.reservedSwift).memory.getObject(self)"
-            let calleeExpr = Self.propertyAccessExpr(objectExpr: objectExpr, propertyName: name)
-            let callExpr = "\(calleeExpr)(\(parameterForwardings.joined(separator: ", ")))"
-            body.write("\(callExpr).then(resolve, reject);")
-        }
-
         func callStaticMethod(on objectExpr: String, name: String) throws {
             let calleeExpr = Self.propertyAccessExpr(objectExpr: objectExpr, propertyName: name)
             return try call(calleeExpr: calleeExpr)
@@ -4235,7 +4234,7 @@ extension BridgeJSLink {
         method: ExportedFunction
     ) throws {
         let thunkBuilder = ImportedThunkBuilder(
-            effects: Effects(isAsync: false, isThrows: false),
+            effects: method.effects,
             returnType: method.returnType,
             context: .exportSwift,
             intrinsicRegistry: intrinsicRegistry

Plugins/BridgeJS/Sources/BridgeJSSkeleton/BridgeJSSkeleton.swift

@@ -607,6 +607,7 @@ public protocol BridgeSkeletonVisitor {
         accessLevel: BridgeJSAccessLevel
     )
     mutating func visitImportedFunction(_ function: ImportedFunctionSkeleton)
+    mutating func visitProtocolMethod(_ method: ExportedFunction, accessLevel: BridgeJSAccessLevel)
 }
 
 public extension BridgeSkeletonVisitor {
@@ -616,6 +617,7 @@ public extension BridgeSkeletonVisitor {
         accessLevel: BridgeJSAccessLevel
     ) {}
     mutating func visitImportedFunction(_ function: ImportedFunctionSkeleton) {}
+    mutating func visitProtocolMethod(_ method: ExportedFunction, accessLevel: BridgeJSAccessLevel) {}
 }
 
 public struct BridgeSkeletonWalker<Visitor: BridgeSkeletonVisitor> {
@@ -681,6 +683,7 @@ public struct BridgeSkeletonWalker<Visitor: BridgeSkeletonVisitor> {
         }
         for proto in skeleton.protocols {
             for method in proto.methods {
+                visitor.visitProtocolMethod(method, accessLevel: currentAccessLevel)
                 walk(method)
             }
             for property in proto.properties {
@@ -1870,6 +1873,12 @@ public struct ClosureSignatureCollectorVisitor: BridgeSkeletonVisitor {
         )
     }
 
+    public mutating func visitProtocolMethod(_ method: ExportedFunction, accessLevel: BridgeJSAccessLevel) {
+        guard method.effects.isAsync else { return }
+
+        recordInjectedSignatures(forReturnType: method.returnType, accessLevel: accessLevel)
+    }
+
     private mutating func recordInjectedSignatures(
         forReturnType returnType: BridgeType,
         accessLevel: BridgeJSAccessLevel

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

@@ -59,6 +59,10 @@ import JavaScriptKit
     func createEnum() -> ExampleEnum
     func handleResult(_ result: Result)
     func getResult() -> Result
+    func validate(_ value: Int) throws(JSException) -> Int
+    func loadLabel(_ key: String) async throws(JSException) -> String
+    func reset() async throws(JSException)
+    func fetchCount() async -> Int
 }
 
 @JS class MyViewController {
@@ -95,6 +99,14 @@ import JavaScriptKit
     @JS func sendHelper(_ helper: Helper) {
         delegate.onHelperUpdated(helper)
     }
+
+    @JS func validateValue(_ value: Int) throws(JSException) -> Int {
+        return try delegate.validate(value)
+    }
+
+    @JS func loadLabel(_ key: String) async throws(JSException) -> String {
+        return try await delegate.loadLabel(key)
+    }
 }
 
 // Protocol array support

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

@@ -228,6 +228,62 @@
             "returnType" : {
               "void" : {
 
+              }
+            }
+          },
+          {
+            "abiName" : "bjs_MyViewController_validateValue",
+            "effects" : {
+              "isAsync" : false,
+              "isStatic" : false,
+              "isThrows" : true
+            },
+            "name" : "validateValue",
+            "parameters" : [
+              {
+                "label" : "_",
+                "name" : "value",
+                "type" : {
+                  "integer" : {
+                    "_0" : {
+                      "isSigned" : true,
+                      "width" : "word"
+                    }
+                  }
+                }
+              }
+            ],
+            "returnType" : {
+              "integer" : {
+                "_0" : {
+                  "isSigned" : true,
+                  "width" : "word"
+                }
+              }
+            }
+          },
+          {
+            "abiName" : "bjs_MyViewController_loadLabel",
+            "effects" : {
+              "isAsync" : true,
+              "isStatic" : false,
+              "isThrows" : true
+            },
+            "name" : "loadLabel",
+            "parameters" : [
+              {
+                "label" : "_",
+                "name" : "key",
+                "type" : {
+                  "string" : {
+
+                  }
+                }
+              }
+            ],
+            "returnType" : {
+              "string" : {
+
               }
             }
           }
@@ -831,6 +887,99 @@
                 "_0" : "Result"
               }
             }
+          },
+          {
+            "abiName" : "bjs_MyViewControllerDelegate_validate",
+            "effects" : {
+              "isAsync" : false,
+              "isStatic" : false,
+              "isThrows" : true
+            },
+            "name" : "validate",
+            "parameters" : [
+              {
+                "label" : "_",
+                "name" : "value",
+                "type" : {
+                  "integer" : {
+                    "_0" : {
+                      "isSigned" : true,
+                      "width" : "word"
+                    }
+                  }
+                }
+              }
+            ],
+            "returnType" : {
+              "integer" : {
+                "_0" : {
+                  "isSigned" : true,
+                  "width" : "word"
+                }
+              }
+            }
+          },
+          {
+            "abiName" : "bjs_MyViewControllerDelegate_loadLabel",
+            "effects" : {
+              "isAsync" : true,
+              "isStatic" : false,
+              "isThrows" : true
+            },
+            "name" : "loadLabel",
+            "parameters" : [
+              {
+                "label" : "_",
+                "name" : "key",
+                "type" : {
+                  "string" : {
+
+                  }
+                }
+              }
+            ],
+            "returnType" : {
+              "string" : {
+
+              }
+            }
+          },
+          {
+            "abiName" : "bjs_MyViewControllerDelegate_reset",
+            "effects" : {
+              "isAsync" : true,
+              "isStatic" : false,
+              "isThrows" : true
+            },
+            "name" : "reset",
+            "parameters" : [
+
+            ],
+            "returnType" : {
+              "void" : {
+
+              }
+            }
+          },
+          {
+            "abiName" : "bjs_MyViewControllerDelegate_fetchCount",
+            "effects" : {
+              "isAsync" : true,
+              "isStatic" : false,
+              "isThrows" : false
+            },
+            "name" : "fetchCount",
+            "parameters" : [
+
+            ],
+            "returnType" : {
+              "integer" : {
+                "_0" : {
+                  "isSigned" : true,
+                  "width" : "word"
+                }
+              }
+            }
           }
         ],
         "name" : "MyViewControllerDelegate",