[decamelize] add linting & enable strict null checks (#18847)

* [decamelize] add linting & enable strict null checks

* [decamelize] reintroduce namespace to support import * syntax to avoid a breaking change for users

types/decamelize/decamelize-tests.ts

@@ -1,5 +1,4 @@
-
 import decamelize = require('decamelize');
 
 decamelize('unicornRainbow');
-decamelize('unicornRainbow', '-');
+decamelize('unicornRainbow', '-');

types/decamelize/index.d.ts

@@ -1,9 +1,9 @@
-// Type definitions for decamelize
+// Type definitions for decamelize 1.2
 // Project: https://github.com/sindresorhus/decamelize
 // Definitions by: Sam Verschueren <https://github.com/samverschueren>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 
+export = decamelize;
 
 declare function decamelize(input: string, separator?: string): string;
-declare namespace decamelize { }
-export = decamelize;
+declare namespace decamelize {}

types/decamelize/tsconfig.json

@@ -6,7 +6,7 @@
         ],
         "noImplicitAny": true,
         "noImplicitThis": true,
-        "strictNullChecks": false,
+        "strictNullChecks": true,
         "baseUrl": "../",
         "typeRoots": [
             "../"
@@ -19,4 +19,4 @@
         "index.d.ts",
         "decamelize-tests.ts"
     ]
-}
+}

types/decamelize/tslint.json

@@ -0,0 +1 @@
+{ "extends": "dtslint/dt.json" }