Deprecate tslint in favour of eslint (#28)

* test: set up eslint, remove tslint and format all files

* test(.eslintignore): add .nyc_output and coverage directories

.eslintignore

@@ -0,0 +1,4 @@
+.nyc_output
+coverage
+dist
+node_modules

.eslintrc.json

@@ -0,0 +1,48 @@
+{
+  "plugins": ["@typescript-eslint", "eslint-comments", "mocha", "promise", "unicorn"],
+  "extends": [
+    "eslint:recommended",
+    "airbnb-typescript/base",
+    "plugin:@typescript-eslint/recommended",
+    "plugin:@typescript-eslint/recommended-requiring-type-checking",
+    "plugin:eslint-comments/recommended",
+    "plugin:mocha/recommended",
+    "plugin:promise/recommended",
+    "plugin:unicorn/recommended",
+    "prettier",
+    "prettier/react",
+    "prettier/@typescript-eslint"
+  ],
+  "env": {
+    "node": true,
+    "browser": true,
+    "mocha": true
+  },
+  "parserOptions": {
+    "project": "tsconfig.json",
+    "createDefaultProgram": true,
+    "ecmaVersion": 2020,
+    "sourceType": "module"
+  },
+  "rules": {
+    "no-use-before-define": ["error", { "functions": false, "classes": true, "variables": true }],
+    "@typescript-eslint/explicit-function-return-type": "off",
+    "@typescript-eslint/no-use-before-define": [
+      "error",
+      { "functions": false, "classes": true, "variables": true, "typedefs": true }
+    ],
+    "react/destructuring-assignment": "off",
+    "react/jsx-filename-extension": "off",
+    // Common abbreviations are known and readable
+    "unicorn/prevent-abbreviations": "off",
+    "unicorn/filename-case": [
+      "error",
+      {
+        "cases": {
+          "camelCase": true,
+          "pascalCase": true
+        }
+      }
+    ]
+  }
+}

.prettierrc.toml

@@ -6,7 +6,7 @@ printWidth = 80
 proseWrap = "always"
 requirePragma = false
 semi = true
-singleQuote = false
+singleQuote = true
 tabWidth = 2
 trailingComma = "all"
 
@@ -19,4 +19,4 @@ tabWidth = 2
 [[overrides]]
 files = "*.md"
 [overrides.options]
-proseWrap = "never"
+proseWrap = "preserve"

.vscode/settings.json

@@ -1,11 +1,9 @@
 {
   "editor.formatOnSave": true,
   "editor.codeActionsOnSave": {
-    "source.fixAll.tslint": true,
     "source.fixAll.eslint": true
   },
   "markdownlint.config": {
-    "list-marker-space": false,
     "no-inline-html": false
   },
   "typescript.tsdk": "node_modules/typescript/lib"

README.md

@@ -206,7 +206,7 @@ The module content will be available as the UMD global `exampleCalculator`.
 The package provides a calculator class.
 
 ```ts
-import Calculator from "example-calculator";
+import Calculator from 'example-calculator';
 const calculator = new Calculator();
 ```
 
@@ -275,12 +275,12 @@ calculator.clear().inverse().value();
 You can also import some operations as standalone functions from their submodules:
 
 ```ts
-import add from "example-calculator/add";
-import sub from "example-calculator/sub";
-import mul from "example-calculator/mul";
-import div from "example-calculator/div";
-import mod from "example-calculator/mod";
-import ln from "example-calculator/ln";
+import add from 'example-calculator/add';
+import sub from 'example-calculator/sub';
+import mul from 'example-calculator/mul';
+import div from 'example-calculator/div';
+import mod from 'example-calculator/mod';
+import ln from 'example-calculator/ln';
 
 console.log(add(1, 1));
 // Prints 2

package.json

@@ -50,7 +50,8 @@
     "posttest:print": "nyc report",
     "posttest:lcov": "nyc report --reporter=lcov",
     "posttest:json": "nyc report --reporter=json",
-    "lint": "tslint --project tsconfig.json",
+    "lint": "eslint './**/*.?(js|jsx|ts|tsx)'",
+    "lint:fix": "eslint './**/*.?(js|jsx|ts|tsx)' --fix",
     "docs": "typedoc",
     "clean:dist": "rimraf ./dist ./.rpt2_cache",
     "clean:node_modules": "rimraf ./node_modules",
@@ -71,11 +72,27 @@
     "@types/chai": "^4.2.11",
     "@types/mocha": "^7.0.2",
     "@types/prettier": "^2.0.0",
+    "@typescript-eslint/eslint-plugin": "^2.30.0",
+    "@typescript-eslint/parser": "^2.30.0",
     "chai": "^4.2.0",
     "codecov": "^3.6.5",
     "commitizen": "^4.0.4",
     "cross-env": "^7.0.2",
     "cz-conventional-changelog": "^3.1.0",
+    "eslint": "^6.8.0",
+    "eslint-config-airbnb-typescript": "^7.2.1",
+    "eslint-config-prettier": "^6.11.0",
+    "eslint-plugin-eslint-comments": "^3.1.2",
+    "eslint-plugin-import": "^2.20.2",
+    "eslint-plugin-jsx-a11y": "^6.2.3",
+    "eslint-plugin-mocha": "^6.3.0",
+    "eslint-plugin-node": "^11.1.0",
+    "eslint-plugin-prettier": "^3.1.3",
+    "eslint-plugin-promise": "^4.2.1",
+    "eslint-plugin-react": "^7.19.0",
+    "eslint-plugin-react-hooks": "^3.0.0",
+    "eslint-plugin-sort-imports-es6-autofix": "^0.5.0",
+    "eslint-plugin-unicorn": "^19.0.1",
     "gh-pages": "^2.2.0",
     "husky": "^4.2.5",
     "mocha": "^7.1.2",
@@ -89,7 +106,6 @@
     "ts-node": "^8.9.1",
     "ts-pkg-scripts": "^0.2.1",
     "tslib": "^1.11.1",
-    "tslint": "^6.1.2",
     "typedoc": "^0.17.6",
     "typescript": "^3.8.3"
   },
@@ -139,5 +155,6 @@
         }
       ]
     ]
-  }
-}
+  },
+  "dependencies": {}
+}

src/Calculator.spec.ts

@@ -1,39 +1,30 @@
-import { expect } from "chai";
-import { describe, it } from "mocha";
+import { describe, it } from 'mocha';
+import { expect } from 'chai';
 
-import Calculator from "./Calculator";
+import Calculator from './Calculator';
 
-describe("Calculator", () => {
-  it("has the correct initial value when no argument is supplied", () => expect(new Calculator().value()).equal(0));
-  it("has the correct initial value when an argument is supplied", () => expect(new Calculator(3).value()).equal(3));
+describe('Calculator', () => {
+  it('has the correct initial value when no argument is supplied', () => expect(new Calculator().value()).equal(0));
+  it('has the correct initial value when an argument is supplied', () => expect(new Calculator(3).value()).equal(3));
 
   const calculator = new Calculator();
 
-  it("can add", () => expect(calculator.add(2).value()).equal(2));
-  it("can sub", () => expect(calculator.sub(1).value()).equal(1));
-  it("can mul", () => expect(calculator.mul(12).value()).equal(12));
-  it("can div", () => expect(calculator.div(2).value()).equal(6));
-  it("can mod", () => expect(calculator.mod(4).value()).equal(2));
-  // prettier-ignore
-  it("can exp", () => expect(calculator.sub(1).exp().value()).equal(Math.E));
-  it("can ln", () => expect(calculator.ln().value()).equal(1));
-  it("can clear", () => expect(calculator.clear().value()).equal(0));
+  it('can add', () => expect(calculator.add(2).value()).equal(2));
+  it('can sub', () => expect(calculator.sub(1).value()).equal(1));
+  it('can mul', () => expect(calculator.mul(12).value()).equal(12));
+  it('can div', () => expect(calculator.div(2).value()).equal(6));
+  it('can mod', () => expect(calculator.mod(4).value()).equal(2));
+  it('can exp', () => expect(calculator.sub(1).exp().value()).equal(Math.E));
+  it('can ln', () => expect(calculator.ln().value()).equal(1));
+  it('can clear', () => expect(calculator.clear().value()).equal(0));
 
-  // prettier-ignore
-  it("can invert", () => expect(calculator.clear().add(2).inverse().value()).equal(1 / 2));
+  it('can invert', () => expect(calculator.clear().add(2).inverse().value()).equal(1 / 2));
 
-  // prettier-ignore
-  it("can sin", () => expect(calculator.clear().sin().value()).equal(0));
-  // prettier-ignore
-  it("can cos", () => expect(calculator.clear().cos().value()).equal(1));
-  // prettier-ignore
-  it("can tan", () => expect(calculator.clear().tan().value()).equal(0));
-  // prettier-ignore
-  it("can sinh", () => expect(calculator.clear().sinh().value()).equal(0));
-  // prettier-ignore
-  it("can cosh", () => expect(calculator.clear().cosh().value()).equal(1));
-  // prettier-ignore
-  it("can tanh", () => expect(calculator.clear().tanh().value()).equal(0));
-  // prettier-ignore
-  it("can asin", () => expect(calculator.clear().asin().value()).equal(0));
+  it('can sin', () => expect(calculator.clear().sin().value()).equal(0));
+  it('can cos', () => expect(calculator.clear().cos().value()).equal(1));
+  it('can tan', () => expect(calculator.clear().tan().value()).equal(0));
+  it('can sinh', () => expect(calculator.clear().sinh().value()).equal(0));
+  it('can cosh', () => expect(calculator.clear().cosh().value()).equal(1));
+  it('can tanh', () => expect(calculator.clear().tanh().value()).equal(0));
+  it('can asin', () => expect(calculator.clear().asin().value()).equal(0));
 });

src/Calculator.ts

@@ -1,15 +1,15 @@
-import add from "./add";
-import div from "./div";
-import ln from "./ln";
-import mod from "./mod";
-import mul from "./mul";
-import sub from "./sub";
+import add from './add';
+import div from './div';
+import ln from './ln';
+import mod from './mod';
+import mul from './mul';
+import sub from './sub';
 
 /** A simple stateful calculator */
 export default class Calculator {
-  protected current: number = 0;
+  protected current = 0;
 
-  constructor(initial: number = 0) {
+  constructor(initial = 0) {
     this.current = initial;
   }
 

src/div.spec.ts

@@ -1,9 +1,9 @@
-import { expect } from "chai";
-import { describe, it } from "mocha";
+import { describe, it } from 'mocha';
+import { expect } from 'chai';
 
-import div from "./div";
+import div from './div';
 
-describe("div", () => {
-  it("works for non-zero argments", () => expect(div(6, 2)).equal(3));
-  it("works for zero arguments", () => expect(div(3, 0)).equal(0));
+describe('div', () => {
+  it('works for non-zero argments', () => expect(div(6, 2)).equal(3));
+  it('works for zero arguments', () => expect(div(3, 0)).equal(0));
 });

src/index.ts

@@ -1,7 +1,7 @@
-export { default as add } from "./add";
-export { default as sub } from "./sub";
-export { default as mul } from "./mul";
-export { default as div } from "./div";
-export { default as ln } from "./ln";
-export { default as mod } from "./mod";
-export { default as Calculator } from "./Calculator";
+export { default as add } from './add';
+export { default as sub } from './sub';
+export { default as mul } from './mul';
+export { default as div } from './div';
+export { default as ln } from './ln';
+export { default as mod } from './mod';
+export { default as Calculator } from './Calculator';

src/ln.spec.ts

@@ -1,12 +1,12 @@
-import { expect } from "chai";
-import { describe, it } from "mocha";
+import { describe, it } from 'mocha';
+import { expect } from 'chai';
 
-import ln from "./ln";
+import ln from './ln';
 
-describe("ln", () => {
-  it("works for non-zero argments", () => expect(ln(1)).equal(0));
-  it("works for non-zero argments", () => expect(ln(Math.E)).equal(1));
-  it("works for zero arguments", () => expect(ln(0)).equal(0));
-  it("works for negative argments", () => expect(ln(-1)).equal(0));
-  it("works for negative argments", () => expect(ln(-Math.E)).equal(1));
+describe('ln', () => {
+  it('works for non-zero argments ln(1)=0', () => expect(ln(1)).equal(0));
+  it('works for non-zero argments ln(e)=1', () => expect(ln(Math.E)).equal(1));
+  it('works for zero arguments ln(0)=0', () => expect(ln(0)).equal(0));
+  it('works for negative argments ln(-1)=0', () => expect(ln(-1)).equal(0));
+  it('works for negative argments ln(-e)=1', () => expect(ln(-Math.E)).equal(1));
 });

src/ln.ts

@@ -4,5 +4,11 @@
  * Returns ln(-n), if `n` is negative and `0` if n is 0
  */
 export default function ln(n: number): number {
-  return n === 0 ? 0 : n < 0 ? ln(-n) : Math.log(n);
+  if (n === 0) {
+    return 0;
+  }
+  if (n < 0) {
+    return ln(-n);
+  }
+  return Math.log(n);
 }

src/mod.spec.ts

@@ -1,9 +1,9 @@
-import { expect } from "chai";
-import { describe, it } from "mocha";
+import { describe, it } from 'mocha';
+import { expect } from 'chai';
 
-import mod from "./mod";
+import mod from './mod';
 
-describe("mod", () => {
-  it("works for non-zero argments", () => expect(mod(6, 4)).equal(2));
-  it("works for zero arguments", () => expect(mod(3, 0)).equal(0));
+describe('mod', () => {
+  it('works for non-zero argments', () => expect(mod(6, 4)).equal(2));
+  it('works for zero arguments', () => expect(mod(3, 0)).equal(0));
 });

src/mod.ts

@@ -1,5 +1,5 @@
 /**
- * The modulus of two numbers
+ * Computes the modulus of two numbers
  *
  * Returns 0, if `b` is 0
  */