Generate a source map for the declaration file

Author: voxpelli

.gitignore

@@ -11,6 +11,7 @@
 
 # Generated types
 *.d.ts
+*.d.ts.map
 
 # Library specific ones
 index.mjs

declaration.tsconfig.json

@@ -6,6 +6,7 @@
   ],
   "compilerOptions": {
     "declaration": true,
+    "declarationMap": true,
     "noEmit": false,
     "emitDeclarationOnly": true
   }

package.json

@@ -17,7 +17,8 @@
   "files": [
     "index.js",
     "index.mjs",
-    "index.d.ts"
+    "index.d.ts",
+    "index.d.ts.map"
   ],
   "scripts": {
     "build:0": "run-s clean",
@@ -109,4 +110,4 @@
     "type-coverage": "^2.14.6",
     "typescript": "^4.1.3"
   }
-}
+}