Add "ban-types" to tslint:latest.

src/configs/latest.ts

@@ -52,6 +52,17 @@ export const rules = {
     "arrow-return-shorthand": true,
     "no-unnecessary-initializer": true,
     "no-misused-new": true,
+
+    // added in v4.5
+    "ban-types": [
+        true,
+        ["Object", "Avoid using the `Object` type. Did you mean `object`?"],
+        ["Function", "Avoid using the `Function` type. Prefer a specific function type, like `() => void`."],
+        ["Boolean", "Avoid using the `Boolean` type. Did you mean `boolean`?"],
+        ["Number", "Avoid using the `Number` type. Did you mean `number`?"],
+        ["String", "Avoid using the `String` type. Did you mean `string`?"],
+        ["Symbol", "Avoid using the `Symbol` type. Did you mean `symbol`?"],
+    ],
 };
 // tslint:enable object-literal-sort-keys
 

src/formatterLoader.ts

@@ -17,23 +17,16 @@
 
 import * as fs from "fs";
 import * as path from "path";
+import {FormatterFunction} from "./index";
 import {camelize} from "./utils";
 
 const moduleDirectory = path.dirname(module.filename);
 const CORE_FORMATTERS_DIRECTORY = path.resolve(moduleDirectory, ".", "formatters");
 
-function isFunction(variable: any): variable is Function {
-    return typeof variable === "function";
-}
-
-function isString(variable: any): variable is string {
-    return typeof variable === "string";
-}
-
-export function findFormatter(name: string | Function, formattersDirectory?: string) {
-    if (isFunction(name)) {
+export function findFormatter(name: string | FormatterFunction, formattersDirectory?: string) {
+    if (typeof name === "function") {
         return name;
-    } else if (isString(name)) {
+    } else if (typeof name === "string") {
         name = name.trim();
         const camelizedName = camelize(`${name}Formatter`);
 

src/index.ts

@@ -38,13 +38,15 @@ export interface LintResult {
     failureCount: number;
     failures: RuleFailure[];
     fixes?: RuleFailure[];
-    format: string | Function;
+    format: string | FormatterFunction;
     output: string;
 }
 
+export type FormatterFunction = (failures: RuleFailure[]) => string;
+
 export interface ILinterOptions {
     fix: boolean;
-    formatter?: string | Function;
+    formatter?: string | FormatterFunction;
     formattersDirectory?: string;
     rulesDirectory?: string | string[];
 }