fix: issue with extender types (#120)

* BREAKING CHANGE: change get() and required() function behaviours

* chore: fix coverage

* Update env-var.d.ts

Co-Authored-By: Phoenix <todofixthis@users.noreply.github.com>

* Update lib/variable.js

Co-Authored-By: Phoenix <todofixthis@users.noreply.github.com>

* address PR feedback

* update README

* add feature list to readme

* more emojis, because why the fuck not

* emoji strategy change

* readme improvements

* rejig things

* remove benefits section

* change tagline

* line break

* line break

* add error message for 5.x get usage. update types

* update readme

* types fix for default()

* fix record and array generics

* chore: bump version and changelog

* fix: issue with extender types

Co-authored-by: Phoenix <todofixthis@users.noreply.github.com>

CHANGELOG.md

@@ -1,3 +1,6 @@
+## 6.1.1 (22/04/20)
+* Fix TS error with *ExtenderTypeOptional* and *ExtenderType* typings (#119)
+
 ## 6.1.0 (20/04/20)
 * Fix TS error with *extraAccessor* typings (#114)
 * Add support for generic types in *asEnum* (#116)

env-var.d.ts

@@ -3,29 +3,29 @@
 
 import { Url } from 'url';
 
-interface IPresentVariable<Extensions = {}> {
+interface IPresentVariable<Exs extends Extensions = {}> {
   /**
    * Converts a bas64 environment variable to ut8
    */
-  convertFromBase64: () => IPresentVariable<Extensions> & Extensions
+  convertFromBase64: () => IPresentVariable<Exs> & Exs
 
   /**
    * Provide an example value that can be used in error output if the variable
    * is not set, or is set to an invalid value
    */
-  example: (example: string) => IPresentVariable<Extensions> & Extensions
+  example: (example: string) => IPresentVariable<Exs> & Exs
 
   /**
    * Set a default value for this variable. This will be used if a value is not
    * set in the process environment
    */
-  default: (value: string|number|Record<string, any>|Array<any>) => IPresentVariable<Extensions> & Extensions;
+  default: (value: string|number|Record<string, any>|Array<any>) => IPresentVariable<Exs> & Exs;
 
   /**
    * Ensures the variable is set on process.env. If it's not set an exception
    * will be thrown. Can pass false to bypass the check.
    */
-  required: (isRequired?: boolean) => IPresentVariable & ExtenderType<Extensions>;
+  required: (isRequired?: boolean) => IPresentVariable & ExtenderType<Exs>;
 
   /**
    * Converts a number to an integer and verifies it's in port ranges 0-65535
@@ -120,29 +120,29 @@ interface IPresentVariable<Extensions = {}> {
   asEnum: <T extends string>(validValues: T[]) => T;
 }
 
-interface IOptionalVariable<Extensions = {}> {
+interface IOptionalVariable<Exs extends Extensions = {}> {
   /**
    * Decodes a base64-encoded environment variable
    */
-  convertFromBase64: () => IOptionalVariable<Extensions> & Extensions;
+  convertFromBase64: () => IOptionalVariable<Exs> & Exs;
 
   /**
    * Provide an example value that can be used in error output if the variable
    * is not set, or is set to an invalid value
    */
-  example: (value: string) => IOptionalVariable<Extensions> & Extensions;
+  example: (value: string) => IOptionalVariable<Exs> & Exs;
 
   /**
    * Set a default value for this variable. This will be used if a value is not
    * set in the process environment
    */
-  default: (value: string|number|Record<string, any>|Array<any>) => IPresentVariable<Extensions> & Extensions;
+  default: (value: string|number|Record<string, any>|Array<any>) => IPresentVariable<Exs> & Exs;
 
   /**
    * Ensures the variable is set on process.env. If it's not set an exception will be thrown.
    * Can pass false to bypass the check
    */
-  required: (isRequired?: boolean) => IPresentVariable & ExtenderType<Extensions>;
+  required: (isRequired?: boolean) => IPresentVariable & ExtenderType<Exs>;
 
   /**
    * Converts a number to an integer and verifies it's in port ranges 0-65535
@@ -267,8 +267,8 @@ interface IEnv<PresentVariable, OptionalVariable> {
 }
 
 // Used internally only to support extension fns
-type ExtenderType<T> = { [P in keyof T]: (...args: any[]) => ReturnType<T[P]> }
-type ExtenderTypeOptional<T> = { [P in keyof T]: (...args: any[]) => ReturnType<T[P]>|undefined }
+type ExtenderType<T extends Extensions> = { [P in keyof T]: (...args: any[]) => ReturnType<T[P]> }
+type ExtenderTypeOptional<T extends Extensions> = { [P in keyof T]: (...args: any[]) => ReturnType<T[P]>|undefined }
 
 export type Extensions = {
   [key: string]: ExtensionFn<any>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "env-var",
-  "version": "6.1.0",
+  "version": "6.1.1",
   "description": "Verification, sanatization, and type coercion for environment variables in Node.js",
   "main": "env-var.js",
   "typings": "env-var.d.ts",
@@ -63,7 +63,7 @@
     "mocha-lcov-reporter": "~1.3.0",
     "nyc": "~15.0.0",
     "standard": "~14.3.0",
-    "typescript": "~3.7.5"
+    "typescript": "~3.8.3"
   },
   "engines": {
     "node": ">=8"