Setup eslint and enforce rules

src/di/types.ts

@@ -1,6 +1,6 @@
-export const DEPENDENCY_KEYS_METADATA_KEY = 'extollo:di:dependencies:ctor';
-export const DEPENDENCY_KEYS_PROPERTY_METADATA_KEY = 'extollo:di:dependencies:properties';
-export const DEPENDENCY_KEYS_SERVICE_TYPE_KEY = 'extollo:di:service_type';
+export const DEPENDENCY_KEYS_METADATA_KEY = 'extollo:di:dependencies:ctor'
+export const DEPENDENCY_KEYS_PROPERTY_METADATA_KEY = 'extollo:di:dependencies:properties'
+export const DEPENDENCY_KEYS_SERVICE_TYPE_KEY = 'extollo:di:service_type'
 
 /**
  * Interface that designates a particular value as able to be constructed.
@@ -13,20 +13,26 @@ export interface Instantiable<T> {
  * Returns true if the given value is instantiable.
  * @param what
  */
-export function isInstantiable<T>(what: any): what is Instantiable<T> {
-    return (typeof what === 'object' || typeof what === 'function') && 'constructor' in what && typeof what.constructor === 'function'
+export function isInstantiable<T>(what: unknown): what is Instantiable<T> {
+    return (
+        Boolean(what)
+        && (typeof what === 'object' || typeof what === 'function')
+        && (what !== null)
+        && 'constructor' in what
+        && typeof what.constructor === 'function'
+    )
 }
 
 /**
  * Type that identifies a value as a static class, even if it is not instantiable.
  */
-export type StaticClass<T, T2> = Function & {prototype: T} & T2
+export type StaticClass<T, T2> = Function & {prototype: T} & T2  // eslint-disable-line @typescript-eslint/ban-types
 
 /**
  * Returns true if the parameter is a static class.
  * @param something
  */
-export function isStaticClass<T, T2>(something: any): something is StaticClass<T, T2> {
+export function isStaticClass<T, T2>(something: unknown): something is StaticClass<T, T2> {
     return typeof something === 'function' && typeof something.prototype !== 'undefined'
 }