Upgrade dependencies and fix ESLint issues.

package.json

@@ -35,15 +35,15 @@
   "devDependencies": {
     "@babel/cli": "^7.10.5",
     "@babel/preset-env": "^7.10.4",
-    "@types/jest": "^24.9.1",
+    "@types/jest": "^26.0.7",
-    "eslint": "^6.8.0",
+    "eslint": "^7.5.0",
-    "eslint-config-airbnb": "^17.1.1",
+    "eslint-config-airbnb": "^18.2.0",
     "eslint-plugin-import": "^2.22.0",
-    "eslint-plugin-jest": "^22.21.0",
+    "eslint-plugin-jest": "^23.18.2",
     "eslint-plugin-jsx-a11y": "^6.3.1",
     "eslint-plugin-react": "^7.20.3",
-    "husky": "^2.7.0",
+    "husky": "^4.2.5",
-    "jest": "^24.9.0"
+    "jest": "^26.1.0"
   },
   "dependencies": {}
 }

src/algorithms/cryptography/polynomial-hash/PolynomialHash.js

@@ -20,7 +20,7 @@ export default class PolynomialHash {
    * @return {number}
    */
   hash(word) {
-    const charCodes = Array.from(word).map(char => this.charToNumber(char));
+    const charCodes = Array.from(word).map((char) => this.charToNumber(char));
 
     let hash = 0;
     for (let charIndex = 0; charIndex < charCodes.length; charIndex += 1) {

src/algorithms/graph/articulation-points/articulationPoints.js

@@ -66,7 +66,7 @@ export default function articulationPoints(graph) {
       // Get minimum low discovery time from all neighbors.
       /** @param {GraphVertex} neighbor */
       visitedSet[currentVertex.getKey()].lowDiscoveryTime = currentVertex.getNeighbors()
-        .filter(earlyNeighbor => earlyNeighbor.getKey() !== previousVertex.getKey())
+        .filter((earlyNeighbor) => earlyNeighbor.getKey() !== previousVertex.getKey())
         /**
          * @param {number} lowestDiscoveryTime
          * @param {GraphVertex} neighbor

src/algorithms/graph/bridges/graphBridges.js

@@ -53,7 +53,7 @@ export default function graphBridges(graph) {
 
       // Check if current node is connected to any early node other then previous one.
       visitedSet[currentVertex.getKey()].lowDiscoveryTime = currentVertex.getNeighbors()
-        .filter(earlyNeighbor => earlyNeighbor.getKey() !== previousVertex.getKey())
+        .filter((earlyNeighbor) => earlyNeighbor.getKey() !== previousVertex.getKey())
         .reduce(
           /**
            * @param {number} lowestDiscoveryTime

src/algorithms/graph/detect-cycle/detectUndirectedCycleUsingDisjointSet.js

@@ -8,9 +8,9 @@ import DisjointSet from '../../../data-structures/disjoint-set/DisjointSet';
 export default function detectUndirectedCycleUsingDisjointSet(graph) {
   // Create initial singleton disjoint sets for each graph vertex.
   /** @param {GraphVertex} graphVertex */
-  const keyExtractor = graphVertex => graphVertex.getKey();
+  const keyExtractor = (graphVertex) => graphVertex.getKey();
   const disjointSet = new DisjointSet(keyExtractor);
-  graph.getAllVertices().forEach(graphVertex => disjointSet.makeSet(graphVertex));
+  graph.getAllVertices().forEach((graphVertex) => disjointSet.makeSet(graphVertex));
 
   // Go trough all graph edges one by one and check if edge vertices are from the
   // different sets. In this case joint those sets together. Do this until you find

src/algorithms/graph/eulerian-path/eulerianPath.js

@@ -75,7 +75,7 @@ export default function eulerianPath(graph) {
       [edgeToDelete] = currentEdges;
     } else {
       // If there are many edges left then we need to peek any of those except bridges.
-      [edgeToDelete] = currentEdges.filter(edge => !bridges[edge.getKey()]);
+      [edgeToDelete] = currentEdges.filter((edge) => !bridges[edge.getKey()]);
     }
 
     // Detect next current vertex.

src/algorithms/graph/hamiltonian-cycle/hamiltonianCycle.js

@@ -20,7 +20,7 @@ function isSafe(adjacencyMatrix, verticesIndices, cycle, vertexCandidate) {
   }
 
   // Check if vertexCandidate is being added to the path for the first time.
-  const candidateDuplicate = cycle.find(vertex => vertex.getKey() === vertexCandidate.getKey());
+  const candidateDuplicate = cycle.find((vertex) => vertex.getKey() === vertexCandidate.getKey());
 
   return !candidateDuplicate;
 }
@@ -61,7 +61,7 @@ function hamiltonianCycleRecursive({
   cycle,
 }) {
   // Clone cycle in order to prevent it from modification by other DFS branches.
-  const currentCycle = [...cycle].map(vertex => new GraphVertex(vertex.value));
+  const currentCycle = [...cycle].map((vertex) => new GraphVertex(vertex.value));
 
   if (vertices.length === currentCycle.length) {
     // Hamiltonian path is found.

src/algorithms/graph/kruskal/kruskal.js

@@ -33,7 +33,7 @@ export default function kruskal(graph) {
   const sortedEdges = new QuickSort(sortingCallbacks).sort(graph.getAllEdges());
 
   // Create disjoint sets for all graph vertices.
-  const keyCallback = graphVertex => graphVertex.getKey();
+  const keyCallback = (graphVertex) => graphVertex.getKey();
   const disjointSet = new DisjointSet(keyCallback);
 
   graph.getAllVertices().forEach((graphVertex) => {

src/algorithms/linked-list/reverse-traversal/__test__/reverseTraversal.test.js

@@ -21,7 +21,6 @@ describe('reverseTraversal', () => {
   });
 });
 
-
 // it('should reverse traversal the linked list with callback', () => {
 //   const linkedList = new LinkedList();
 //

src/algorithms/math/fourier-transform/__test__/FourierTester.js

@@ -244,7 +244,7 @@ export default class FourierTester {
       const { input, output: expectedOutput } = testCase;
 
       // Try to split input signal into sequence of pure sinusoids.
-      const formattedInput = input.map(sample => sample.amplitude);
+      const formattedInput = input.map((sample) => sample.amplitude);
       const currentOutput = fourierTransform(formattedInput);
 
       // Check the signal has been split into proper amount of sub-signals.

src/algorithms/math/fourier-transform/fastFourierTransform.js

@@ -46,8 +46,8 @@ export default function fastFourierTransform(inputData, inverse = false) {
   for (let blockLength = 2; blockLength <= N; blockLength *= 2) {
     const imaginarySign = inverse ? -1 : 1;
     const phaseStep = new ComplexNumber({
-      re: Math.cos(2 * Math.PI / blockLength),
+      re: Math.cos((2 * Math.PI) / blockLength),
-      im: imaginarySign * Math.sin(2 * Math.PI / blockLength),
+      im: imaginarySign * Math.sin((2 * Math.PI) / blockLength),
     });
 
     for (let blockStart = 0; blockStart < N; blockStart += blockLength) {

src/algorithms/math/pascal-triangle/pascalTriangle.js

@@ -9,7 +9,7 @@ export default function pascalTriangle(lineNumber) {
 
   for (let numIndex = 1; numIndex < currentLineSize; numIndex += 1) {
     // See explanation of this formula in README.
-    currentLine[numIndex] = currentLine[numIndex - 1] * (lineNumber - numIndex + 1) / numIndex;
+    currentLine[numIndex] = (currentLine[numIndex - 1] * (lineNumber - numIndex + 1)) / numIndex;
   }
 
   return currentLine;

src/algorithms/math/radian/__test__/degreeToRadian.test.js

@@ -6,7 +6,7 @@ describe('degreeToRadian', () => {
     expect(degreeToRadian(45)).toBe(Math.PI / 4);
     expect(degreeToRadian(90)).toBe(Math.PI / 2);
     expect(degreeToRadian(180)).toBe(Math.PI);
-    expect(degreeToRadian(270)).toBe(3 * Math.PI / 2);
+    expect(degreeToRadian(270)).toBe((3 * Math.PI) / 2);
     expect(degreeToRadian(360)).toBe(2 * Math.PI);
   });
 });

src/algorithms/math/radian/__test__/radianToDegree.test.js

@@ -6,7 +6,7 @@ describe('radianToDegree', () => {
     expect(radianToDegree(Math.PI / 4)).toBe(45);
     expect(radianToDegree(Math.PI / 2)).toBe(90);
     expect(radianToDegree(Math.PI)).toBe(180);
-    expect(radianToDegree(3 * Math.PI / 2)).toBe(270);
+    expect(radianToDegree((3 * Math.PI) / 2)).toBe(270);
     expect(radianToDegree(2 * Math.PI)).toBe(360);
   });
 });

src/algorithms/search/interpolation-search/interpolationSearch.js

@@ -31,7 +31,7 @@ export default function interpolationSearch(sortedArray, seekElement) {
     }
 
     // Do interpolation of the middle index.
-    const middleIndex = leftIndex + Math.floor(valueDelta * indexDelta / rangeDelta);
+    const middleIndex = leftIndex + Math.floor((valueDelta * indexDelta) / rangeDelta);
 
     // If we've found the element just return its position.
     if (sortedArray[middleIndex] === seekElement) {

src/algorithms/sets/combinations/combineWithRepetitions.js

@@ -7,7 +7,7 @@ export default function combineWithRepetitions(comboOptions, comboLength) {
   // If the length of the combination is 1 then each element of the original array
   // is a combination itself.
   if (comboLength === 1) {
-    return comboOptions.map(comboOption => [comboOption]);
+    return comboOptions.map((comboOption) => [comboOption]);
   }
 
   // Init combinations array.

src/algorithms/sets/combinations/combineWithoutRepetitions.js

@@ -7,7 +7,7 @@ export default function combineWithoutRepetitions(comboOptions, comboLength) {
   // If the length of the combination is 1 then each element of the original array
   // is a combination itself.
   if (comboLength === 1) {
-    return comboOptions.map(comboOption => [comboOption]);
+    return comboOptions.map((comboOption) => [comboOption]);
   }
 
   // Init combinations array.

src/algorithms/sets/knapsack-problem/Knapsack.js

@@ -150,7 +150,6 @@ export default class Knapsack {
     }
   }
 
-
   // Solve unbounded knapsack problem.
   // Greedy approach.
   solveUnboundedKnapsackProblem() {

src/algorithms/sets/permutations/permutateWithRepetitions.js

@@ -8,7 +8,7 @@ export default function permutateWithRepetitions(
   permutationLength = permutationOptions.length,
 ) {
   if (permutationLength === 1) {
-    return permutationOptions.map(permutationOption => [permutationOption]);
+    return permutationOptions.map((permutationOption) => [permutationOption]);
   }
 
   // Init permutations array.

src/algorithms/uncategorized/n-queens/nQueens.js

@@ -81,7 +81,6 @@ function nQueensRecursive(solutions, previousQueensPositions, queensCount, rowIn
   return false;
 }
 
-
 /**
  * @param {number} queensCount
  * @return {QueenPosition[][]}

src/data-structures/bloom-filter/BloomFilter.js

@@ -16,7 +16,7 @@ export default class BloomFilter {
     const hashValues = this.getHashValues(item);
 
     // Set each hashValue index to true.
-    hashValues.forEach(val => this.storage.setValue(val));
+    hashValues.forEach((val) => this.storage.setValue(val));
   }
 
   /**

src/data-structures/bloom-filter/__test__/BloomFilter.test.js

@@ -51,7 +51,7 @@ describe('BloomFilter', () => {
   });
 
   it('should insert strings correctly and return true when checking for inserted values', () => {
-    people.forEach(person => bloomFilter.insert(person));
+    people.forEach((person) => bloomFilter.insert(person));
 
     expect(bloomFilter.mayContain('Bruce Wayne')).toBe(true);
     expect(bloomFilter.mayContain('Clark Kent')).toBe(true);

src/data-structures/disjoint-set/__test__/DisjointSet.test.js

@@ -94,7 +94,7 @@ describe('DisjointSet', () => {
   });
 
   it('should do basic manipulations on disjoint set with custom key extractor', () => {
-    const keyExtractor = value => value.key;
+    const keyExtractor = (value) => value.key;
 
     const disjointSet = new DisjointSet(keyExtractor);
 

src/data-structures/doubly-linked-list/DoublyLinkedList.js

@@ -218,7 +218,7 @@ export default class DoublyLinkedList {
    * @return {DoublyLinkedList}
    */
   fromArray(values) {
-    values.forEach(value => this.append(value));
+    values.forEach((value) => this.append(value));
 
     return this;
   }
@@ -228,7 +228,7 @@ export default class DoublyLinkedList {
    * @return {string}
    */
   toString(callback) {
-    return this.toArray().map(node => node.toString(callback)).toString();
+    return this.toArray().map((node) => node.toString(callback)).toString();
   }
 
   /**

src/data-structures/doubly-linked-list/__test__/DoublyLinkedList.test.js

@@ -164,7 +164,7 @@ describe('DoublyLinkedList', () => {
       .append(nodeValue1)
       .prepend(nodeValue2);
 
-    const nodeStringifier = value => `${value.key}:${value.value}`;
+    const nodeStringifier = (value) => `${value.key}:${value.value}`;
 
     expect(linkedList.toString(nodeStringifier)).toBe('key2:2,key1:1');
   });
@@ -195,12 +195,12 @@ describe('DoublyLinkedList', () => {
       .append({ value: 2, key: 'test2' })
       .append({ value: 3, key: 'test3' });
 
-    const node = linkedList.find({ callback: value => value.key === 'test2' });
+    const node = linkedList.find({ callback: (value) => value.key === 'test2' });
 
     expect(node).toBeDefined();
     expect(node.value.value).toBe(2);
     expect(node.value.key).toBe('test2');
-    expect(linkedList.find({ callback: value => value.key === 'test5' })).toBeNull();
+    expect(linkedList.find({ callback: (value) => value.key === 'test5' })).toBeNull();
   });
 
   it('should find node by means of custom compare function', () => {

src/data-structures/doubly-linked-list/__test__/DoublyLinkedListNode.test.js

@@ -48,7 +48,7 @@ describe('DoublyLinkedListNode', () => {
   it('should convert node to string with custom stringifier', () => {
     const nodeValue = { value: 1, key: 'test' };
     const node = new DoublyLinkedListNode(nodeValue);
-    const toStringCallback = value => `value: ${value.value}, key: ${value.key}`;
+    const toStringCallback = (value) => `value: ${value.value}, key: ${value.key}`;
 
     expect(node.toString(toStringCallback)).toBe('value: 1, key: test');
   });

src/data-structures/graph/GraphVertex.js

@@ -64,7 +64,7 @@ export default class GraphVertex {
    * @return {GraphEdge[]}
    */
   getEdges() {
-    return this.edges.toArray().map(linkedListNode => linkedListNode.value);
+    return this.edges.toArray().map((linkedListNode) => linkedListNode.value);
   }
 
   /**
@@ -80,7 +80,7 @@ export default class GraphVertex {
    */
   hasEdge(requiredEdge) {
     const edgeNode = this.edges.find({
-      callback: edge => edge === requiredEdge,
+      callback: (edge) => edge === requiredEdge,
     });
 
     return !!edgeNode;
@@ -92,7 +92,7 @@ export default class GraphVertex {
    */
   hasNeighbor(vertex) {
     const vertexNode = this.edges.find({
-      callback: edge => edge.startVertex === vertex || edge.endVertex === vertex,
+      callback: (edge) => edge.startVertex === vertex || edge.endVertex === vertex,
     });
 
     return !!vertexNode;
@@ -123,7 +123,7 @@ export default class GraphVertex {
    * @return {GraphVertex}
    */
   deleteAllEdges() {
-    this.getEdges().forEach(edge => this.deleteEdge(edge));
+    this.getEdges().forEach((edge) => this.deleteEdge(edge));
 
     return this;
   }

src/data-structures/hash-table/HashTable.js

@@ -52,7 +52,7 @@ export default class HashTable {
     const keyHash = this.hash(key);
     this.keys[key] = keyHash;
     const bucketLinkedList = this.buckets[keyHash];
-    const node = bucketLinkedList.find({ callback: nodeValue => nodeValue.key === key });
+    const node = bucketLinkedList.find({ callback: (nodeValue) => nodeValue.key === key });
 
     if (!node) {
       // Insert new node.
@@ -71,7 +71,7 @@ export default class HashTable {
     const keyHash = this.hash(key);
     delete this.keys[key];
     const bucketLinkedList = this.buckets[keyHash];
-    const node = bucketLinkedList.find({ callback: nodeValue => nodeValue.key === key });
+    const node = bucketLinkedList.find({ callback: (nodeValue) => nodeValue.key === key });
 
     if (node) {
       return bucketLinkedList.delete(node.value);
@@ -86,7 +86,7 @@ export default class HashTable {
    */
   get(key) {
     const bucketLinkedList = this.buckets[this.hash(key)];
-    const node = bucketLinkedList.find({ callback: nodeValue => nodeValue.key === key });
+    const node = bucketLinkedList.find({ callback: (nodeValue) => nodeValue.key === key });
 
     return node ? node.value.value : undefined;
   }

src/data-structures/hash-table/__test__/HashTable.test.js

@@ -35,7 +35,7 @@ describe('HashTable', () => {
     expect(hashTable.has('b')).toBe(true);
     expect(hashTable.has('c')).toBe(true);
 
-    const stringifier = value => `${value.key}:${value.value}`;
+    const stringifier = (value) => `${value.key}:${value.value}`;
 
     expect(hashTable.buckets[0].toString(stringifier)).toBe('c:earth');
     expect(hashTable.buckets[1].toString(stringifier)).toBe('a:sky,d:ocean');

src/data-structures/linked-list/LinkedList.js

@@ -180,7 +180,7 @@ export default class LinkedList {
    * @return {LinkedList}
    */
   fromArray(values) {
-    values.forEach(value => this.append(value));
+    values.forEach((value) => this.append(value));
 
     return this;
   }
@@ -205,7 +205,7 @@ export default class LinkedList {
    * @return {string}
    */
   toString(callback) {
-    return this.toArray().map(node => node.toString(callback)).toString();
+    return this.toArray().map((node) => node.toString(callback)).toString();
   }
 
   /**

src/data-structures/linked-list/__test__/LinkedList.test.js

@@ -146,7 +146,7 @@ describe('LinkedList', () => {
       .append(nodeValue1)
       .prepend(nodeValue2);
 
-    const nodeStringifier = value => `${value.key}:${value.value}`;
+    const nodeStringifier = (value) => `${value.key}:${value.value}`;
 
     expect(linkedList.toString(nodeStringifier)).toBe('key2:2,key1:1');
   });
@@ -177,12 +177,12 @@ describe('LinkedList', () => {
       .append({ value: 2, key: 'test2' })
       .append({ value: 3, key: 'test3' });
 
-    const node = linkedList.find({ callback: value => value.key === 'test2' });
+    const node = linkedList.find({ callback: (value) => value.key === 'test2' });
 
     expect(node).toBeDefined();
     expect(node.value.value).toBe(2);
     expect(node.value.key).toBe('test2');
-    expect(linkedList.find({ callback: value => value.key === 'test5' })).toBeNull();
+    expect(linkedList.find({ callback: (value) => value.key === 'test5' })).toBeNull();
   });
 
   it('should create linked list from array', () => {

src/data-structures/linked-list/__test__/LinkedListNode.test.js

@@ -39,7 +39,7 @@ describe('LinkedListNode', () => {
   it('should convert node to string with custom stringifier', () => {
     const nodeValue = { value: 1, key: 'test' };
     const node = new LinkedListNode(nodeValue);
-    const toStringCallback = value => `value: ${value.value}, key: ${value.key}`;
+    const toStringCallback = (value) => `value: ${value.value}, key: ${value.key}`;
 
     expect(node.toString(toStringCallback)).toBe('value: 1, key: test');
   });

src/data-structures/queue/__test__/Queue.test.js

@@ -22,7 +22,7 @@ describe('Queue', () => {
     queue.enqueue({ value: 'test1', key: 'key1' });
     queue.enqueue({ value: 'test2', key: 'key2' });
 
-    const stringifier = value => `${value.key}:${value.value}`;
+    const stringifier = (value) => `${value.key}:${value.value}`;
 
     expect(queue.toString(stringifier)).toBe('key1:test1,key2:test2');
     expect(queue.dequeue().value).toBe('test1');

src/data-structures/stack/Stack.js

@@ -54,7 +54,7 @@ export default class Stack {
   toArray() {
     return this.linkedList
       .toArray()
-      .map(linkedListNode => linkedListNode.value);
+      .map((linkedListNode) => linkedListNode.value);
   }
 
   /**

src/data-structures/stack/__test__/Stack.test.js

@@ -56,7 +56,7 @@ describe('Stack', () => {
     stack.push({ value: 'test1', key: 'key1' });
     stack.push({ value: 'test2', key: 'key2' });
 
-    const stringifier = value => `${value.key}:${value.value}`;
+    const stringifier = (value) => `${value.key}:${value.value}`;
 
     expect(stack.toString(stringifier)).toBe('key2:test2,key1:test1');
     expect(stack.pop().value).toBe('test2');