Merge pull request #643 from apollographql/change/result-type

Switch to built-in `Result` type
apollographql · Jul 17, 2019 · 1b0b68d · 1b0b68d
2 parents 2bcbbff + 98e261f
commit 1b0b68d
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Showing 6 changed files with 42 additions and 61 deletions.
diff --git a/Apollo.xcodeproj/project.pbxproj b/Apollo.xcodeproj/project.pbxproj
@@ -11,6 +11,7 @@
 		5AC6CA4322AAF7B200B7C94D /* GraphQLHTTPMethod.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5AC6CA4222AAF7B200B7C94D /* GraphQLHTTPMethod.swift */; };
 		9B95EDC022CAA0B000702BB2 /* GETTransformerTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9B95EDBF22CAA0AF00702BB2 /* GETTransformerTests.swift */; };
 		9BA1244A22D8A8EA00BF1D24 /* JSONSerialziation+Sorting.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9BA1244922D8A8EA00BF1D24 /* JSONSerialziation+Sorting.swift */; };
+		9BA1245E22DE116B00BF1D24 /* Result+Helpers.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9BA1245D22DE116B00BF1D24 /* Result+Helpers.swift */; };
 		9BDE43D122C6655300FD7C7F /* Cancellable.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9BDE43D022C6655200FD7C7F /* Cancellable.swift */; };
 		9BDE43DD22C6705300FD7C7F /* GraphQLHTTPResponseError.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9BDE43DC22C6705300FD7C7F /* GraphQLHTTPResponseError.swift */; };
 		9BDE43DF22C6708600FD7C7F /* GraphQLHTTPRequestError.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9BDE43DE22C6708600FD7C7F /* GraphQLHTTPRequestError.swift */; };
@@ -96,7 +97,6 @@
 		9FE941D01E62C771007CDD89 /* Promise.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9FE941CF1E62C771007CDD89 /* Promise.swift */; };
 		9FEB050D1DB5732300DA3B44 /* JSONSerializationFormat.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9FEB050C1DB5732300DA3B44 /* JSONSerializationFormat.swift */; };
 		9FEC15B41E681DAD00D461B4 /* Collections.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9FEC15B31E681DAD00D461B4 /* Collections.swift */; };
-		9FEC15B91E6965E300D461B4 /* Result.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9FEC15B81E6965E300D461B4 /* Result.swift */; };
 		9FF33D811E48B98200F608A4 /* HTTPNetworkTransport.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9F4DAF2D1E48B84B00EBFF0B /* HTTPNetworkTransport.swift */; };
 		9FF90A611DDDEB100034C3B6 /* GraphQLResponse.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9FF90A5B1DDDEB100034C3B6 /* GraphQLResponse.swift */; };
 		9FF90A651DDDEB100034C3B6 /* GraphQLExecutor.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9FF90A5C1DDDEB100034C3B6 /* GraphQLExecutor.swift */; };
@@ -254,6 +254,7 @@
 		90690D2522433CAF00FC2E54 /* Apollo-Target-TestSupport.xcconfig */ = {isa = PBXFileReference; lastKnownFileType = text.xcconfig; path = "Apollo-Target-TestSupport.xcconfig"; sourceTree = "<group>"; };
 		9B95EDBF22CAA0AF00702BB2 /* GETTransformerTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = GETTransformerTests.swift; sourceTree = "<group>"; };
 		9BA1244922D8A8EA00BF1D24 /* JSONSerialziation+Sorting.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "JSONSerialziation+Sorting.swift"; sourceTree = "<group>"; };
+		9BA1245D22DE116B00BF1D24 /* Result+Helpers.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Result+Helpers.swift"; sourceTree = "<group>"; };
 		9BDE43D022C6655200FD7C7F /* Cancellable.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Cancellable.swift; sourceTree = "<group>"; };
 		9BDE43DC22C6705300FD7C7F /* GraphQLHTTPResponseError.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = GraphQLHTTPResponseError.swift; sourceTree = "<group>"; };
 		9BDE43DE22C6708600FD7C7F /* GraphQLHTTPRequestError.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = GraphQLHTTPRequestError.swift; sourceTree = "<group>"; };
@@ -355,7 +356,6 @@
 		9FE941CF1E62C771007CDD89 /* Promise.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Promise.swift; sourceTree = "<group>"; };
 		9FEB050C1DB5732300DA3B44 /* JSONSerializationFormat.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = JSONSerializationFormat.swift; sourceTree = "<group>"; };
 		9FEC15B31E681DAD00D461B4 /* Collections.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Collections.swift; sourceTree = "<group>"; };
-		9FEC15B81E6965E300D461B4 /* Result.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Result.swift; sourceTree = "<group>"; };
 		9FF90A5B1DDDEB100034C3B6 /* GraphQLResponse.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = GraphQLResponse.swift; sourceTree = "<group>"; };
 		9FF90A5C1DDDEB100034C3B6 /* GraphQLExecutor.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = GraphQLExecutor.swift; sourceTree = "<group>"; };
 		9FF90A6A1DDDEB420034C3B6 /* InputValueEncodingTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = InputValueEncodingTests.swift; sourceTree = "<group>"; };
@@ -639,8 +639,8 @@
 			children = (
 				9F578D8F1D8D2CB300C0EA36 /* Utilities.swift */,
 				9FCDFD221E33A0D8007519DC /* AsynchronousOperation.swift */,
-				9FEC15B81E6965E300D461B4 /* Result.swift */,
 				9FE941CF1E62C771007CDD89 /* Promise.swift */,
+				9BA1245D22DE116B00BF1D24 /* Result+Helpers.swift */,
 				9F19D8431EED568200C57247 /* ResultOrPromise.swift */,
 				9FEC15B31E681DAD00D461B4 /* Collections.swift */,
 				9FADC8491E6B0B2300C677E6 /* Locking.swift */,
@@ -1129,7 +1129,6 @@
 				9F7BA89922927A3700999B3B /* ResponsePath.swift in Sources */,
 				9FC9A9BD1E2C271C0023C4D5 /* RecordSet.swift in Sources */,
 				9BF1A95122CA6E71005292C2 /* GraphQLGETTransformer.swift in Sources */,
-				9FEC15B91E6965E300D461B4 /* Result.swift in Sources */,
 				9FADC84F1E6B865E00C677E6 /* DataLoader.swift in Sources */,
 				9FF90A611DDDEB100034C3B6 /* GraphQLResponse.swift in Sources */,
 				9F27D4641D40379500715680 /* JSONStandardTypeConversions.swift in Sources */,
@@ -1139,6 +1138,7 @@
 				9BDE43DF22C6708600FD7C7F /* GraphQLHTTPRequestError.swift in Sources */,
 				5AC6CA4322AAF7B200B7C94D /* GraphQLHTTPMethod.swift in Sources */,
 				9FE941D01E62C771007CDD89 /* Promise.swift in Sources */,
+				9BA1245E22DE116B00BF1D24 /* Result+Helpers.swift in Sources */,
 				9FC750631D2A59F600458D91 /* ApolloClient.swift in Sources */,
 				9F86B6901E65533D00B885FF /* GraphQLResponseGenerator.swift in Sources */,
 				9FC9A9C21E2D3CAF0023C4D5 /* GraphQLInputValue.swift in Sources */,

diff --git a/Sources/Apollo/Promise.swift b/Sources/Apollo/Promise.swift
@@ -32,10 +32,10 @@ public final class Promise<Value> {
   private let lock = Mutex()
   private var state: State<Value>
 
-  private typealias ResultHandler<Value> = (Result<Value>) -> Void
+  private typealias ResultHandler<Value> = (Result<Value, Error>) -> Void
   private var resultHandlers: [ResultHandler<Value>] = []
 
-  public init(resolved result: Result<Value>) {
+  public init(resolved result: Result<Value, Error>) {
     state = .resolved(result)
   }
 
@@ -72,7 +72,7 @@ public final class Promise<Value> {
     }
   }
 
-  public var result: Result<Value>? {
+  public var result: Result<Value, Error>? {
     return lock.withLock {
       switch state {
       case .pending:
@@ -96,7 +96,7 @@ public final class Promise<Value> {
   public func await() throws -> Value {
     let semaphore = DispatchSemaphore(value: 0)
 
-    var result: Result<Value>? = nil
+    var result: Result<Value, Error>? = nil
 
     whenResolved {
       result = $0
@@ -105,7 +105,7 @@ public final class Promise<Value> {
 
     semaphore.wait()
 
-    return try result!.valueOrError()
+    return try result!.get()
   }
 
   @discardableResult public func andThen(_ whenFulfilled: @escaping (Value) throws -> Void) -> Promise<Value> {
@@ -208,7 +208,7 @@ public final class Promise<Value> {
     resolve(.failure(error))
   }
 
-  private func resolve(_ result: Result<Value>) {
+  private func resolve(_ result: Result<Value, Error>) {
     lock.withLock {
       guard state.isPending else { return }
 
@@ -237,7 +237,7 @@ public final class Promise<Value> {
 
 private enum State<Value> {
   case pending
-  case resolved(Result<Value>)
+  case resolved(Result<Value, Error>)
 
   var isPending: Bool {
     if case .pending = self {

diff --git a/Sources/Apollo/Result+Helpers.swift b/Sources/Apollo/Result+Helpers.swift
@@ -0,0 +1,25 @@
+import Foundation
+
+extension Result {
+
+  /// Converts the result into an optional value. Returns the value for a `success` case and nil for a `failure` case.
+  var value: Success?  {
+    switch self {
+    case .success(let value):
+      return value
+    case .failure:
+      return nil
+    }
+  }
+
+  /// Converts the result into an optional error. Returns the error for a `failure` case and nil for a `success` case.
+  /// Mostly useful for testing to make sure appropriate errors are received.
+  var error: Failure? {
+    switch self {
+    case .success:
+      return nil
+    case .failure(let error):
+      return error
+    }
+  }
+}
diff --git a/Sources/Apollo/Result.swift b/Sources/Apollo/Result.swift
diff --git a/Sources/Apollo/ResultOrPromise.swift b/Sources/Apollo/ResultOrPromise.swift
@@ -2,15 +2,15 @@ import Dispatch
 
 public func whenAll<Value>(_ resultsOrPromises: [ResultOrPromise<Value>], notifyOn queue: DispatchQueue = .global()) -> ResultOrPromise<[Value]> {
   onlyResults: do {
-    var results: [Result<Value>] = []
+    var results: [Result<Value, Error>] = []
     for resultOrPromise in resultsOrPromises {
       guard case .result(let result) = resultOrPromise else {
         break onlyResults
       }
       results.append(result)
     }
     do {
-      let values = try results.map { try $0.valueOrError() }
+      let values = try results.map { try $0.get() }
       return .result(.success(values))
     } catch {
       return .result(.failure(error))
@@ -37,7 +37,7 @@ public func whenAll<Value>(_ resultsOrPromises: [ResultOrPromise<Value>], notify
 }
 
 public enum ResultOrPromise<Value> {
-  case result(Result<Value>)
+  case result(Result<Value, Error>)
   case promise(Promise<Value>)
 
   public init(_ body: () throws -> Value) {
@@ -49,7 +49,7 @@ public enum ResultOrPromise<Value> {
     }
   }
 
-  public var result: Result<Value>? {
+  public var result: Result<Value, Error>? {
     switch self {
     case .result(let result):
       return result
@@ -61,7 +61,7 @@ public enum ResultOrPromise<Value> {
   public func await() throws -> Value {
     switch self {
     case .result(let result):
-      return try result.valueOrError()
+      return try result.get()
     case .promise(let promise):
       return try promise.await()
     }

diff --git a/Tests/ApolloTestSupport/XCTestCase+Promise.swift b/Tests/ApolloTestSupport/XCTestCase+Promise.swift
@@ -11,6 +11,6 @@ extension XCTestCase {
 
     waitForExpectations(timeout: 5)
 
-    return try promise.result!.valueOrError()
+    return try promise.result!.get()
   }
 }