Add TypeScript definition (#8)

.travis.yml

@@ -1,5 +1,6 @@
 language: node_js
 node_js:
+  - '11'
   - '10'
   - '8'
   - '6'

index.d.ts

@@ -0,0 +1,14 @@
+/**
+List of the Node.js builtin modules.
+
+@example
+```
+import builtinModules = require('builtin-modules');
+
+console.log(builtinModules);
+//=> ['assert', 'buffer', …]
+```
+*/
+declare const builtinModules: readonly string[];
+
+export = builtinModules;

index.js

@@ -5,6 +5,7 @@ const blacklist = [
 	'sys'
 ];
 
+// eslint-disable-next-line node/no-deprecated-api
 module.exports = (builtinModules || Object.keys(process.binding('natives')))
 	.filter(x => !/^_|^(internal|v8|node-inspect)\/|\//.test(x) && !blacklist.includes(x))
 	.sort();

index.test-d.ts

@@ -0,0 +1,9 @@
+import {expectType, expectError} from 'tsd';
+import builtinModules = require('.');
+import builtinModulesStatic = require ('./static');
+
+expectType<readonly string[]>(builtinModules);
+expectError<string[]>(builtinModules);
+
+expectType<readonly string[]>(builtinModulesStatic);
+expectError<string[]>(builtinModulesStatic);

package.json

@@ -13,12 +13,14 @@
 		"node": ">=6"
 	},
 	"scripts": {
-		"test": "xo && ava",
+		"test": "xo && ava && tsd",
 		"make": "node make.js"
 	},
 	"files": [
 		"index.js",
+		"index.d.ts",
 		"static.js",
+		"static.d.ts",
 		"builtin-modules.json"
 	],
 	"keywords": [
@@ -34,7 +36,8 @@
 		"names"
 	],
 	"devDependencies": {
-		"ava": "*",
-		"xo": "*"
+		"ava": "^1.4.1",
+		"tsd": "^0.7.2",
+		"xo": "^0.24.0"
 	}
 }

static.d.ts

@@ -0,0 +1,14 @@
+/**
+Static list of the Node.js builtin modules.
+
+@example
+```
+import builtinModulesStatic = require('builtin-modules/static');
+
+console.log(builtinModulesStatic);
+//=> ['assert', 'buffer', …]
+```
+*/
+declare const builtinModulesStatic: readonly string[];
+
+export = builtinModulesStatic;