Added basic SwiftLint config file. Fixing all linting errors.

.swiftlint.yml

@@ -0,0 +1,25 @@
+cyclomatic_complexity: 12
+file_length: 550
+function_body_length: 80
+function_parameter_count: 8
+line_length: 150
+type_body_length: 300
+variable_name:
+  min_length:
+    error: 1
+    warning: 1
+  excluded:
+    - N
+
+disabled_rules:
+  - valid_docs
+
+custom_rules:
+  smiley_face:
+    name: "Smiley Face"
+    regex: "(\:\))"
+    match_kinds: 
+      - comment
+      - string
+    message: "A closing parenthesis smiley :) creates a half-hearted smile, and thus is not preferred. Use :]"
+    severity: warning

AVL Tree/AVLTree.playground/Contents.swift

@@ -24,4 +24,4 @@ tree.delete(5)
 tree.delete(2)
 tree.delete(1)
 tree.delete(4)
-tree.delete(3)
+tree.delete(3)

AVL Tree/Tests/AVLTreeTests.swift

@@ -9,15 +9,15 @@
 import XCTest
 
 class AVLTreeTests: XCTestCase {
-  
-  var tree : AVLTree<Int, String>?
+
+  var tree: AVLTree<Int, String>?
 
   override func setUp() {
     super.setUp()
-    
+
     tree = AVLTree()
   }
-  
+
   override func tearDown() {
     // Put teardown code here. This method is called after the invocation of each test method in the class.
     super.tearDown()
@@ -60,8 +60,8 @@ class AVLTreeTests: XCTestCase {
   }
 
   func testEmptyInitialization() {
-    let tree = AVLTree<Int,String>()
-    
+    let tree = AVLTree<Int, String>()
+
     XCTAssertEqual(tree.size, 0)
     XCTAssertNil(tree.root)
   }
@@ -71,45 +71,45 @@ class AVLTreeTests: XCTestCase {
       self.tree?.insert(5, "E")
     }
   }
-  
+
   func testMultipleInsertionsPerformance() {
     self.measureBlock {
       self.tree?.autopopulateWithNodes(50)
     }
   }
-  
+
   func testSearchExistentOnSmallTreePerformance() {
     self.measureBlock {
       self.tree?.search(2)
     }
   }
-  
+
   func testSearchExistentElementOnLargeTreePerformance() {
     self.measureBlock {
       self.tree?.autopopulateWithNodes(500)
       self.tree?.search(400)
     }
   }
-  
+
   func testMinimumOnPopulatedTree() {
     self.tree?.autopopulateWithNodes(500)
     let min = self.tree?.root?.minimum()
     XCTAssertNotNil(min, "Minimum function not working")
   }
-  
+
   func testMinimumOnSingleTreeNode() {
     let treeNode = TreeNode(key: 1, payload: "A")
     let min = treeNode.minimum()
-    
+
     XCTAssertNotNil(min, "Minimum on single node should be returned")
-    XCTAssertEqual(min?.payload,treeNode.payload)
+    XCTAssertEqual(min?.payload, treeNode.payload)
   }
-  
+
   func testDeleteExistentKey() {
     self.tree?.delete(1)
     XCTAssertNil(self.tree?.search(1), "Key should not exist anymore")
   }
-  
+
   func testDeleteNotExistentKey() {
     self.tree?.delete(1056)
     XCTAssertNil(self.tree?.search(1056), "Key should not exist")
@@ -122,15 +122,15 @@ class AVLTreeTests: XCTestCase {
       XCTAssertEqual(tree.size, i + 1, "Insert didn't update size correctly!")
     }
   }
-  
+
   func testDelete() {
     let permutations = [
       [5, 1, 4, 2, 3],
       [2, 3, 1, 5, 4],
       [4, 5, 3, 2, 1],
       [3, 2, 5, 4, 1],
     ]
-    
+
     for p in permutations {
       let tree = AVLTree<Int, String>()
 
@@ -151,8 +151,8 @@ class AVLTreeTests: XCTestCase {
 }
 
 extension AVLTree where Key : SignedIntegerType {
-  func autopopulateWithNodes(count : Int) {
-    var k : Key = 1
+  func autopopulateWithNodes(count: Int) {
+    var k: Key = 1
     for _ in 0...count {
       self.insert(k)
       k = k + 1
@@ -185,5 +185,3 @@ extension AVLTree where Key : SignedIntegerType {
     }
   }
 }
-
-

AVL Tree/Tests/TreeNodeTests.swift

@@ -9,50 +9,50 @@
 import XCTest
 
 class TreeNodeTests: XCTestCase {
-    
-    var root : TreeNode<String,String>?
-    var left : TreeNode<String,String>?
-    var right : TreeNode<String,String>?
-    
+
+    var root: TreeNode<String, String>?
+    var left: TreeNode<String, String>?
+    var right: TreeNode<String, String>?
+
     override func setUp() {
         super.setUp()
 
-        left = TreeNode<String,String>(key: "Name", payload: "Left")
-        right = TreeNode<String,String>(key: "Name", payload: "Right")
-        root = TreeNode<String,String>(key: "Name", payload: "Root", leftChild: left, rightChild: right, parent: nil, height: 0)
+        left = TreeNode<String, String>(key: "Name", payload: "Left")
+        right = TreeNode<String, String>(key: "Name", payload: "Right")
+        root = TreeNode<String, String>(key: "Name", payload: "Root", leftChild: left, rightChild: right, parent: nil, height: 0)
     }
-    
+
     override func tearDown() {
         // Put teardown code here. This method is called after the invocation of each test method in the class.
         super.tearDown()
     }
-    
-    
+
+
     func testSingleNodeCreationNOPayload() {
-        let treeNode = TreeNode<String,String>(key: "Building")
+        let treeNode = TreeNode<String, String>(key: "Building")
         XCTAssertNil(treeNode.payload, "Payload for this case should be nil")
     }
-    
+
     func testSingleNodeCreationWithPayload() {
         XCTAssertNotNil(self.root!, "Payload for this case should not be nil")
     }
-    
+
     func testIsRoot() {
         XCTAssertTrue(self.root!.isRoot)
     }
-    
+
     func testNotIsLeaf() {
         XCTAssertFalse(self.root!.isLeaf, "root node is not leaf")
     }
-    
+
     func testNotIsLeftChild() {
         XCTAssertFalse(self.root!.isLeftChild, "root node is not left child")
     }
-    
+
     func testNotIsRightChild() {
         XCTAssertFalse(self.root!.isRightChild, "root node is not right child")
     }
-    
+
     func testIsLeftChild() {
         XCTAssertTrue(self.left!.isLeftChild)
     }
@@ -64,21 +64,21 @@ class TreeNodeTests: XCTestCase {
     func isLeaf() {
         XCTAssertTrue(self.left!.isLeaf)
     }
-    
+
     func testHasAnyChild() {
         XCTAssertTrue(self.root!.hasAnyChild)
     }
-    
+
     func testNotHasAnyChild() {
         XCTAssertFalse(self.left!.hasAnyChild)
     }
-    
+
     func testHasBothChildren() {
         XCTAssertTrue(self.root!.hasBothChildren)
     }
-    
+
     func testNotHasBothChildren() {
         XCTAssertFalse(self.left!.hasBothChildren)
     }
-    
+
 }

All-Pairs Shortest Paths/APSP/APSP/APSP.swift

@@ -9,7 +9,9 @@ import Foundation
 import Graph
 
 /**
- `APSPAlgorithm` is a protocol for encapsulating an All-Pairs Shortest Paths algorithm. It provides a single function `apply` that accepts a subclass of `AbstractGraph` and returns an object conforming to `APSPResult`.
+ `APSPAlgorithm` is a protocol for encapsulating an All-Pairs Shortest Paths algorithm.
+ It provides a single function `apply` that accepts a subclass of `AbstractGraph` and
+ returns an object conforming to `APSPResult`.
  */
 public protocol APSPAlgorithm {
 
@@ -21,7 +23,8 @@ public protocol APSPAlgorithm {
 }
 
 /**
- `APSPResult` is a protocol defining functions `distance` and `path`, allowing for opaque queries into the actual data structures that represent the APSP solution according to the algorithm used.
+ `APSPResult` is a protocol defining functions `distance` and `path`, allowing for opaque
+ queries into the actual data structures that represent the APSP solution according to the algorithm used.
  */
 public protocol APSPResult {
 

All-Pairs Shortest Paths/APSP/APSP/FloydWarshall.swift

@@ -51,12 +51,16 @@ public struct FloydWarshall<T where T: Hashable>: APSPAlgorithm {
   }
 
   /**
-   For each iteration of `intermediateIdx`, perform the comparison for the dynamic algorith, checking for each pair of start/end vertices, whether a path taken through another vertex produces a shorter path.
+   For each iteration of `intermediateIdx`, perform the comparison for the dynamic algorith,
+   checking for each pair of start/end vertices, whether a path taken through another vertex
+   produces a shorter path.
 
    - complexity: `Θ(V^2)` time/space
-   - returns: a tuple containing the next distance matrix with weights of currently known shortest paths and the corresponding predecessor matrix
+   - returns: a tuple containing the next distance matrix with weights of currently known
+   shortest paths and the corresponding predecessor matrix
    */
-  static private func nextStep<T>(intermediateIdx: Int, previousDistances: Distances, previousPredecessors: Predecessors, graph: AbstractGraph<T>) -> StepResult {
+  static private func nextStep<T>(intermediateIdx: Int, previousDistances: Distances,
+                               previousPredecessors: Predecessors, graph: AbstractGraph<T>) -> StepResult {
 
     let vertexCount = graph.vertices.count
     var nextDistances = Array(count: vertexCount, repeatedValue: Array(count: vertexCount, repeatedValue: Double.infinity))
@@ -85,9 +89,11 @@ public struct FloydWarshall<T where T: Hashable>: APSPAlgorithm {
 
   }
 
-  /** 
-   We need to map the graph's weight domain onto the one required by the algorithm: the graph stores either a weight as a `Double` or `nil` if no edge exists between two vertices, but the algorithm needs a lack of an edge represented as ∞ for the `min` comparison to work correctly.
-
+  /**
+   We need to map the graph's weight domain onto the one required by the algorithm: the graph
+   stores either a weight as a `Double` or `nil` if no edge exists between two vertices, but
+   the algorithm needs a lack of an edge represented as ∞ for the `min` comparison to work correctly.
+
    - complexity: `Θ(V^2)` time/space
    - returns: weighted adjacency matrix in form ready for processing with Floyd-Warshall
    */
@@ -116,7 +122,7 @@ public struct FloydWarshall<T where T: Hashable>: APSPAlgorithm {
 
   /**
    Make the initial predecessor index matrix. Initially each value is equal to it's row index, it's "from" index when querying into it.
-   
+
    - complexity: `Θ(V^2)` time/space
   */
   static private func constructInitialPredecessorMatrix(distances: Distances) -> Predecessors {
@@ -139,17 +145,20 @@ public struct FloydWarshall<T where T: Hashable>: APSPAlgorithm {
 }
 
 /**
- `FloydWarshallResult` encapsulates the result of the computation, namely the minimized distance adjacency matrix, and the matrix of predecessor indices.
-
- It conforms to the `APSPResult` procotol which provides methods to retrieve distances and paths between given pairs of start and end nodes.
+ `FloydWarshallResult` encapsulates the result of the computation, namely the
+ minimized distance adjacency matrix, and the matrix of predecessor indices.
+
+ It conforms to the `APSPResult` procotol which provides methods to retrieve
+ distances and paths between given pairs of start and end nodes.
  */
 public struct FloydWarshallResult<T where T: Hashable>: APSPResult {
 
   private var weights: Distances
   private var predecessors: Predecessors
 
   /**
-   - returns: the total weight of the path from a starting vertex to a destination. This value is the minimal connected weight between the two vertices, or `nil` if no path exists
+   - returns: the total weight of the path from a starting vertex to a destination.
+   This value is the minimal connected weight between the two vertices, or `nil` if no path exists
    - complexity: `Θ(1)` time/space
    */
   public func distance(fromVertex from: Vertex<T>, toVertex to: Vertex<T>) -> Double? {
@@ -159,7 +168,8 @@ public struct FloydWarshallResult<T where T: Hashable>: APSPResult {
   }
 
   /**
-   - returns: the reconstructed path from a starting vertex to a destination, as an array containing the data property of each vertex, or `nil` if no path exists
+   - returns: the reconstructed path from a starting vertex to a destination,
+   as an array containing the data property of each vertex, or `nil` if no path exists
    - complexity: `Θ(V)` time, `Θ(V^2)` space
    */
   public func path(fromVertex from: Vertex<T>, toVertex to: Vertex<T>, inGraph graph: AbstractGraph<T>) -> [T]? {
@@ -175,11 +185,13 @@ public struct FloydWarshallResult<T where T: Hashable>: APSPResult {
   }
 
   /**
-   The recursive component to rebuilding the shortest path between two vertices using the predecessor matrix.
+   The recursive component to rebuilding the shortest path between
+   two vertices using the predecessor matrix.
 
    - returns: the list of predecessors discovered so far
    */
-  private func recursePathFrom(fromVertex from: Vertex<T>, toVertex to: Vertex<T>, path: [Vertex<T>], inGraph graph: AbstractGraph<T>) -> [Vertex<T>]? {
+  private func recursePathFrom(fromVertex from: Vertex<T>, toVertex to: Vertex<T>, path: [Vertex<T>],
+                                          inGraph graph: AbstractGraph<T>) -> [Vertex<T>]? {
 
     if from.index == to.index {
       return [ from, to ]
@@ -198,7 +210,6 @@ public struct FloydWarshallResult<T where T: Hashable>: APSPResult {
     }
 
     return nil
-
   }
 
 }