Merge pull request #169 from norio-nomura/nn-handle-sourcekitd-error

handle sourcekitd error

CHANGELOG.md

@@ -2,11 +2,15 @@
 
 ##### Breaking
 
-* None.
+* Change `SwiftDocs.init(file:arguments:)` to
+  `SwiftDocs.init?(file:arguments:)`  
+  [Norio Nomura](https://github.com/norio-nomura)
 
 ##### Enhancements
 
-* None.
+* Add `Request.failableSend()` that can handle SourceKitService crashes.
+  `sourcekitten doc` does not stop when SourceKitService crashes.  
+  [Norio Nomura](https://github.com/norio-nomura)
 
 ##### Bug Fixes
 

Source/SourceKittenFramework/File.swift

@@ -169,8 +169,8 @@ public final class File {
         var dictionary = dictionary
         let offsetMap = generateOffsetMap(documentedTokenOffsets, dictionary: dictionary)
         for offset in offsetMap.keys.reverse() { // Do this in reverse to insert the doc at the correct offset
-            let response = processDictionary(Request.sendCursorInfoRequest(cursorInfoRequest, atOffset: Int64(offset))!, cursorInfoRequest: nil, syntaxMap: syntaxMap)
-            if let kind = SwiftDocKey.getKind(response),
+            if let response = Request.sendCursorInfoRequest(cursorInfoRequest, atOffset: Int64(offset)).map({ processDictionary($0, cursorInfoRequest: nil, syntaxMap: syntaxMap) }),
+                kind = SwiftDocKey.getKind(response),
                 _ = SwiftDeclarationKind(rawValue: kind),
                 parentOffset = offsetMap[offset].flatMap({ Int64($0) }),
                 inserted = insertDoc(response, parent: dictionary, offset: parentOffset) {

Source/SourceKittenFramework/Request.swift

@@ -91,6 +91,10 @@ private func fromSourceKit(sourcekitObject: sourcekitd_variant_t) -> SourceKitRe
 /// dispatch_once_t token used to only initialize SourceKit once per session.
 private var sourceKitInitializationToken: dispatch_once_t = 0
 
+/// dispatch_semaphore_t used when waiting for sourcekitd to be restored.
+private var sourceKitWaitingRestoredSemaphore = dispatch_semaphore_create(0)
+private let sourceKitWaitingRestoredTimeout = Int64(10 * NSEC_PER_SEC)
+
 /// SourceKit UID to String map.
 private var uidStringMap = [sourcekitd_uid_t: String]()
 
@@ -241,7 +245,7 @@ public enum Request {
             return nil
         }
         sourcekitd_request_dictionary_set_int64(request, sourcekitd_uid_get_from_cstr(SwiftDocKey.Offset.rawValue), offset)
-        return Request.CustomRequest(request).send()
+        return try? Request.CustomRequest(request).failableSend()
     }
 
     /**
@@ -257,6 +261,72 @@ public enum Request {
         defer { sourcekitd_response_dispose(response) }
         return fromSourceKit(sourcekitd_response_get_value(response)) as! [String: SourceKitRepresentable]
     }
+
+    /// A enum representation of SOURCEKITD_ERROR_*
+    public enum Error: ErrorType, CustomStringConvertible {
+        case ConnectionInterrupted(String?)
+        case Invalid(String?)
+        case Failed(String?)
+        case Cancelled(String?)
+        case Unknown(String?)
+
+        /// A textual representation of `self`.
+        public var description: String {
+            return getDescription() ?? "no description"
+        }
+
+        private func getDescription() -> String? {
+            switch self {
+            case .ConnectionInterrupted(let string): return string
+            case .Invalid(let string): return string
+            case .Failed(let string): return string
+            case .Cancelled(let string): return string
+            case .Unknown(let string): return string
+            }
+        }
+
+        private init(response: sourcekitd_response_t) {
+            let description = String(UTF8String: sourcekitd_response_error_get_description(response))
+            switch sourcekitd_response_error_get_kind(response) {
+            case SOURCEKITD_ERROR_CONNECTION_INTERRUPTED: self = .ConnectionInterrupted(description)
+            case SOURCEKITD_ERROR_REQUEST_INVALID: self = .Invalid(description)
+            case SOURCEKITD_ERROR_REQUEST_FAILED: self = .Failed(description)
+            case SOURCEKITD_ERROR_REQUEST_CANCELLED: self = .Cancelled(description)
+            default: self = .Unknown(description)
+            }
+        }
+    }
+
+    /**
+    Sends the request to SourceKit and return the response as an [String: SourceKitRepresentable].
+     
+    - returns: SourceKit output as a dictionary.
+    - throws: Request.Error on fail ()
+    */
+    public func failableSend() throws -> [String: SourceKitRepresentable] {
+        dispatch_once(&sourceKitInitializationToken) {
+            sourcekitd_initialize()
+            sourcekitd_set_notification_handler() { response in
+                if !sourcekitd_response_is_error(response) {
+                    fflush(stdout)
+                    fputs("sourcekitten: connection to SourceKitService restored!\n", stderr)
+                    dispatch_semaphore_signal(sourceKitWaitingRestoredSemaphore)
+                }
+                sourcekitd_response_dispose(response)
+            }
+        }
+        let response = sourcekitd_send_request_sync(sourcekitObject)
+        defer { sourcekitd_response_dispose(response) }
+        if sourcekitd_response_is_error(response) {
+            let error = Request.Error(response: response)
+            if case .ConnectionInterrupted = error {
+                dispatch_semaphore_wait(sourceKitWaitingRestoredSemaphore,
+                    dispatch_time(DISPATCH_TIME_NOW, sourceKitWaitingRestoredTimeout))
+            }
+            throw error
+        }
+        return fromSourceKit(sourcekitd_response_get_value(response)) as! [String: SourceKitRepresentable]
+    }
 }
 
 // MARK: CustomStringConvertible

Source/SourceKittenFramework/SwiftDocs.swift

@@ -25,12 +25,19 @@ public struct SwiftDocs {
     - parameter file:      Swift file to document.
     - parameter arguments: compiler arguments to pass to SourceKit.
     */
-    public init(file: File, arguments: [String]) {
-        self.init(
-            file: file,
-            dictionary: Request.EditorOpen(file).send(),
-            cursorInfoRequest: Request.cursorInfoRequestForFilePath(file.path, arguments: arguments)
-        )
+    public init?(file: File, arguments: [String]) {
+        do {
+            self.init(
+                file: file,
+                dictionary: try Request.EditorOpen(file).failableSend(),
+                cursorInfoRequest: Request.cursorInfoRequestForFilePath(file.path, arguments: arguments)
+            )
+        } catch let error as Request.Error {
+            fputs(error.description, stderr)
+            return nil
+        } catch {
+            return nil
+        }
     }
 
     /**

Source/SourceKittenFrameworkTests/SwiftDocsTests.swift

@@ -30,7 +30,7 @@ func compareJSONStringWithFixturesName(name: String, jsonString: String) {
 
 func compareDocsWithFixturesName(name: String) {
     let swiftFilePath = fixturesDirectory + name + ".swift"
-    let docs = SwiftDocs(file: File(path: swiftFilePath)!, arguments: ["-j4", swiftFilePath])
+    let docs = SwiftDocs(file: File(path: swiftFilePath)!, arguments: ["-j4", swiftFilePath])!
 
     let escapedFixturesDirectory = fixturesDirectory.stringByReplacingOccurrencesOfString("/", withString: "\\/")
     let comparisonString = String(docs).stringByReplacingOccurrencesOfString(escapedFixturesDirectory, withString: "")

Source/sourcekitten/DocCommand.swift

@@ -43,8 +43,8 @@ struct DocCommand: CommandType {
             return .Failure(.InvalidArgument(description: "at least 5 arguments are required when using `--single-file`"))
         }
         let sourcekitdArguments = Array<String>(args[4..<args.count])
-        if let file = File(path: args[3]) {
-            let docs = SwiftDocs(file: file, arguments: sourcekitdArguments)
+        if let file = File(path: args[3]),
+            docs = SwiftDocs(file: file, arguments: sourcekitdArguments) {
             print(docs)
             return .Success()
         }

Source/sourcekitten/main.swift

@@ -7,18 +7,25 @@
 //
 
 import Darwin
+import Foundation
 import Commandant
 
-let registry = CommandRegistry<SourceKittenError>()
-registry.register(CompleteCommand())
-registry.register(DocCommand())
-registry.register(SyntaxCommand())
-registry.register(StructureCommand())
-registry.register(VersionCommand())
+// `sourcekitd_set_notification_handler()` set the handler to be executed on main thread queue.
+// So, we vacate main thread to `dispatch_main()`.
+dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0)) {
+    let registry = CommandRegistry<SourceKittenError>()
+    registry.register(CompleteCommand())
+    registry.register(DocCommand())
+    registry.register(SyntaxCommand())
+    registry.register(StructureCommand())
+    registry.register(VersionCommand())
 
-let helpCommand = HelpCommand(registry: registry)
-registry.register(helpCommand)
+    let helpCommand = HelpCommand(registry: registry)
+    registry.register(helpCommand)
 
-registry.main(defaultVerb: "help") { error in
-    fputs("\(error)\n", stderr)
+    registry.main(defaultVerb: "help") { error in
+        fputs("\(error)\n", stderr)
+    }
 }
+
+dispatch_main()