feat: set up TypeScript declaration files generation

This process was based on a TypeScript official guide: https://www.typescriptlang.org/docs/handbook/declaration-files/dts-from-js.html.

.gitignore

@@ -26,7 +26,6 @@ DerivedData
 
 *.xcuserstate
 
-
 *.hprof
 
 # Android/IntelliJ
@@ -44,7 +43,6 @@ local.properties
 npm-debug.log
 yarn-error.log
 
-
 # BUCK
 buck-out/
 \.buckd/
@@ -66,3 +64,4 @@ buck-out/
 *.bundle
 sample/ios/Podfile.lock
 sample/android/app/google-services.json
+typescript/*

package.json

@@ -1,20 +1,25 @@
 {
-    "name": "react-native-emarsys-wrapper",
-    "version": "1.17.0",
-    "description": "React Native wrapper for Emarsys SDK",
-    "main": "index.js",
-    "type": "module",
-    "scripts": {
-        "test": "echo \"Error: no test specified\" && exit 1"
-    },
-    "keywords": [
-        "react-native",
-        "Emarsys"
-    ],
-    "author": "emarsys",
-    "license": "MIT",
-    "peerDependencies": {
-        "react": ">=17.0.2",
-        "react-native": ">=0.67.3"
-    }
+  "name": "react-native-emarsys-wrapper",
+  "version": "1.17.0",
+  "description": "React Native wrapper for Emarsys SDK",
+  "main": "index.js",
+  "types": "typescript/index.d.ts",
+  "type": "module",
+  "scripts": {
+    "prepare": "tsc",
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "keywords": [
+    "react-native",
+    "Emarsys"
+  ],
+  "author": "emarsys",
+  "license": "MIT",
+  "devDependencies": {
+    "typescript": ">=3.7.2"
+  },
+  "peerDependencies": {
+    "react": ">=17.0.2",
+    "react-native": ">=0.67.3"
+  }
 }

tsconfig.json

@@ -0,0 +1,17 @@
+{
+  // Tells TypeScript where to look for files to work with.
+  "include": ["index.js", "src/**/*"],
+  "compilerOptions": {
+    // Tells TypeScript to read JS files, as normally they are ignored as source files.
+    "allowJs": true,
+    // Generate .d.ts files.
+    "declaration": true,
+    // This compiler run should only output .d.ts files.
+    "emitDeclarationOnly": true,
+    // Types should go into this directory.
+    // Removing this option will place the .d.ts files next to their .js source files.
+    "outDir": "typescript",
+    // Generate declaration files to go to js file when using IDE functions like "Go to Definition".
+    "declarationMap": true
+  }
+}