Merge branch 'master' of github.com:zcash/ZcashLightClientKit

ZcashLightClientKit/Block/Processor/CompactBlockDownloadOperation.swift

@@ -11,7 +11,7 @@ import Foundation
 class CompactBlockDownloadOperation: ZcashOperation {
     
     override var isConcurrent: Bool { false }
-       
+    
     override var isAsynchronous: Bool { false }
     
     private var downloader: CompactBlockDownloading

ZcashLightClientKit/Block/Processor/CompactBlockProcessor.swift

@@ -335,7 +335,11 @@ public class CompactBlockProcessor {
             }
         }
     }
-    
+    /**
+        processes new blocks on the given range based on the configuration set for this instance
+     the way operations are queued is implemented based on the following good practice https://forums.developer.apple.com/thread/25761
+     
+     */
     func processNewBlocks(range: CompactBlockRange) {
         
         self.backoffTimer?.invalidate()
@@ -346,9 +350,7 @@ public class CompactBlockProcessor {
         let downloadBlockOperation = CompactBlockDownloadOperation(downloader: self.downloader, range: range)
         
         downloadBlockOperation.startedHandler = { [weak self] in
-         
                 self?.state = .downloading
-            
         }
         
         downloadBlockOperation.errorHandler = { [weak self] (error) in
@@ -358,9 +360,12 @@ public class CompactBlockProcessor {
                 self.fail(error)
            
         }
-        
         let validateChainOperation = CompactBlockValidationOperation(rustWelding: self.rustBackend, cacheDb: cfg.cacheDb, dataDb: cfg.dataDb)
         
+        let downloadValidateAdapterOperation = BlockOperation {
+            validateChainOperation.error = downloadBlockOperation.error
+        }
+        
         validateChainOperation.completionHandler = { (finished, cancelled) in
             guard !cancelled else {
                 LoggerProxy.debug("Warning: operation cancelled")
@@ -396,6 +401,9 @@ public class CompactBlockProcessor {
         
         let scanBlocksOperation = CompactBlockScanningOperation(rustWelding: self.rustBackend, cacheDb: cfg.cacheDb, dataDb: cfg.dataDb)
         
+        let validateScanningAdapterOperation = BlockOperation {
+            scanBlocksOperation.error = validateChainOperation.error
+        }
         scanBlocksOperation.startedHandler = { [weak self] in
                 self?.state = .scanning
         }
@@ -417,9 +425,15 @@ public class CompactBlockProcessor {
             
         }
         
-        scanBlocksOperation.addDependency(downloadBlockOperation)
-        scanBlocksOperation.addDependency(validateChainOperation)
-        queue.addOperations([downloadBlockOperation, validateChainOperation, scanBlocksOperation], waitUntilFinished: false)
+        downloadValidateAdapterOperation.addDependency(downloadBlockOperation)
+        validateChainOperation.addDependency(downloadValidateAdapterOperation)
+        scanBlocksOperation.addDependency(validateScanningAdapterOperation)
+    
+        queue.addOperations([downloadBlockOperation,
+                             downloadValidateAdapterOperation,
+                             validateChainOperation,
+                             validateScanningAdapterOperation,
+                             scanBlocksOperation], waitUntilFinished: false)
         
     }
     

ZcashLightClientKit/Block/Processor/CompactBlockValidationInformation.swift

@@ -41,6 +41,7 @@ class CompactBlockValidationOperation: ZcashOperation {
             let error = CompactBlockValidationError.validationFailed(height: BlockHeight(result))
             self.error = error
             LoggerProxy.debug("block scanning failed with error: \(String(describing: self.error))")
+            self.cancel()
             self.fail()
             return
         }

ZcashLightClientKit/Block/Processor/ZcashOperation.swift

@@ -29,9 +29,7 @@ class ZcashOperation: Operation {
         completionBlock = { [weak self] in
             guard let self = self, let handler = self.completionHandler else { return }
             
-            //            self.handlerDispatchQueue.async {
             handler(self.isFinished, self.isCancelled)
-            //            }
         }
     }
     
@@ -47,7 +45,7 @@ class ZcashOperation: Operation {
     }
     
     func shouldCancel() -> Bool {
-        isCancelled || dependencyCancelled()
+        self.error != nil || isCancelled || dependencyCancelled()
     }
     
     func dependencyCancelled() -> Bool {

ZcashLightClientKitTests/CompactBlockReorgTests.swift

@@ -115,9 +115,10 @@ class CompactBlockReorgTests: XCTestCase {
                    downloadStartedExpect,
                    startedValidatingNotificationExpectation,
                    startedScanningNotificationExpectation,
+                
                    reorgNotificationExpectation,
                    idleNotificationExpectation,
-                   ], timeout: 10,enforceOrder: true)
+                   ], timeout: 3000,enforceOrder: true)
     }
     
     private func expectedBatches(currentHeight: BlockHeight, targetHeight: BlockHeight, batchSize: Int) -> Int {