enhancement/array-extension (#51)

* moved split function into array extension * fixed label * fixed code
yeeth · Feb 13, 2019 · d4a3d28 · d4a3d28
1 parent d7722da
commit d4a3d28
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Showing 4 changed files with 27 additions and 11 deletions.
diff --git a/Sources/BeaconChain/BeaconChain.swift b/Sources/BeaconChain/BeaconChain.swift
@@ -90,15 +90,6 @@ extension BeaconChain {
         return index
     }
 
-    static func split<T>(values: [T], splitCount: Int) -> [[T]] {
-
-        let listLength = values.count
-
-        return stride(from: 0, to: values.count, by: splitCount).map {
-            Array(values[(listLength * $0 / splitCount) ..< (listLength * ($0 + 1) / splitCount)])
-        }
-    }
-
     static func getShuffling(seed: Bytes32, validators: [Validator], epoch: EpochNumber) -> [[ValidatorIndex]] {
         let activeValidatorIndices = getActiveValidatorIndices(validators: validators, epoch: epoch)
         let committeesPerEpoch = getEpochCommitteeCount(activeValidatorCount: validators.count)
@@ -107,7 +98,7 @@ extension BeaconChain {
             activeValidatorIndices[getPermutedIndex(index: Int($0), listSize: activeValidatorIndices.count, seed: seed)]
         }
 
-        return split(values: shuffledActiveValidatorIndices, splitCount: committeesPerEpoch)
+        return shuffledActiveValidatorIndices.split(count: committeesPerEpoch)
     }
 }
 

diff --git a/Sources/BeaconChain/Extensions/Array.swift b/Sources/BeaconChain/Extensions/Array.swift
@@ -0,0 +1,13 @@
+import Foundation
+
+extension Array {
+
+    func split(count: Int) -> [[Element]] {
+        let length = self.count
+
+        return (0..<count).map {
+            Array(self[(length * $0 / count) ..< (length * ($0 + 1) / count)])
+        }
+    }
+
+}
diff --git a/Tests/BeaconChainTests/Extensions/ArrayTests.swift b/Tests/BeaconChainTests/Extensions/ArrayTests.swift
@@ -0,0 +1,11 @@
+import XCTest
+@testable import BeaconChain
+
+final class ArrayTests: XCTestCase {
+
+    func testSplit() {
+        let array = [0, 1, 2, 3]
+        XCTAssertEqual([[0, 1], [2, 3]], array.split(count: 2))
+    }
+
+}
diff --git a/Tests/BeaconChainTests/XCTestManifests.swift b/Tests/BeaconChainTests/XCTestManifests.swift
@@ -4,7 +4,8 @@ import XCTest
 public func allTests() -> [XCTestCaseEntry] {
     return [
         testCase(BeaconChainTests.allTests),
-        testCase(StateTransitionTests.allTests)
+        testCase(ArrayTests.allTests),
+//        testCase(StateTransitionTests.allTests)
     ]
 }
 #endif