Change addTransformation() to accept a transformation instance as well as a string (#309)

Author: patrick-tolosa

__TESTS__/unit/transformation/transformation.test.ts

@@ -1,4 +1,5 @@
 import {Transformation} from "../../../src/transformation/Transformation";
+import {scale} from "../../../src/actions/resize";
 
 describe('Tests for ImageTransformation', () => {
   let tx: Transformation = null;
@@ -15,6 +16,15 @@ describe('Tests for ImageTransformation', () => {
     expect(tx.toString()).toContain('w_100/w_200/w_300');
   });
 
+  it('Accepts a transforamtion instance to addTransformation', () => {
+    const tx1 = new Transformation().resize(scale().width(100));
+    const tx2 = new Transformation().resize(scale().width(500));
+
+    tx2.addTransformation(tx1);
+    tx2.resize(scale().width(200));
+    expect(tx2.toString()).toContain('c_scale,w_500/c_scale,w_100/c_scale,w_200');
+  });
+
   it('Throws when passing a slash to an action', () => {
     expect(() => {
       tx.addAction('w_100/w_200/w_300');

src/assets/CloudinaryTransformable.ts

@@ -223,6 +223,15 @@ class CloudinaryTransformable extends CloudinaryFile {
     return this;
   }
 
+  /**
+   * @description Extend your transformation with another transformation
+   * @param { string | SDK.Transformation } tx
+   */
+  addTransformation(tx: string | Transformation): this {
+    this.transformation.addTransformation(tx);
+    return this;
+  }
+
   /**
    * @desc A proxy to {@link SDK.Transformation| Transformation} - Calls the same method contained in this.transformation
    * @return {string}

src/transformation/Transformation.ts

@@ -47,13 +47,18 @@ class Transformation {
   }
 
   /**
-   * @description Allows the injection of a raw transformation as a string into the transformation
-   * @param {string} stringTransformation
+   * @description Allows the injection of a raw transformation as a string into the transformation, or a Transformation instance that was previously created
+   * @param {string | SDK.Transformation} tx
    * @example transformation.addTransformation('w_100/w_200/w_300');
    * @return {this}
    */
-  addTransformation(stringTransformation: string): this {
-    this.actions.push(stringTransformation);
+  addTransformation(tx: string | Transformation): this {
+    if (tx instanceof Transformation) {
+    // Concat the new actions into the existing actions
+      this.actions = this.actions.concat(tx.actions);
+    } else {
+      this.actions.push(tx);
+    }
     return this;
   }