(#371) Added early returns to image processor + test case

Author: s1hofmann

Diff for: lib/provider/image/jimp-image-processor.class.spec.ts

@@ -0,0 +1,60 @@
+import { Image } from "../../image.class";
+import { Point } from "../../point.class";
+import JimpImageProcessor from "./jimp-image-processor.class";
+
+const imageWidth = 10;
+const imageHeight = 20;
+
+describe("JimpImageProcessor", () => {
+  it.each([[new Point(-1, 5)], [new Point(imageWidth + 5, 5)]])(
+    `should reject on out of bounds x coordinates`,
+    async (outOfBoundsPoint: Point) => {
+      // GIVEN
+      const inputImage = new Image(
+        imageWidth,
+        imageHeight,
+        Buffer.from([0, 0, 0]),
+        3,
+        "input_image",
+        4,
+        4
+      );
+      const SUT = new JimpImageProcessor();
+
+      // WHEN
+      const result = SUT.colorAt(inputImage, outOfBoundsPoint);
+
+      // THEN
+      await expect(result).rejects.toBe(
+        `Query location out of bounds. Should be in range 0 <= x < image.width, is ${outOfBoundsPoint.x}`
+      );
+    }
+  );
+
+  it.each([[new Point(5, -1)], [new Point(5, imageHeight + 10)]])(
+    `should reject on out of bounds y coordinates`,
+    async (outOfBoundsPoint: Point) => {
+      // GIVEN
+      const imageWidth = 10;
+      const imageHeight = 20;
+      const inputImage = new Image(
+        imageWidth,
+        imageHeight,
+        Buffer.from([0, 0, 0]),
+        3,
+        "input_image",
+        4,
+        4
+      );
+      const SUT = new JimpImageProcessor();
+
+      // WHEN
+      const result = SUT.colorAt(inputImage, outOfBoundsPoint);
+
+      // THEN
+      await expect(result).rejects.toBe(
+        `Query location out of bounds. Should be in range 0 <= y < image.height, is ${outOfBoundsPoint.y}`
+      );
+    }
+  );
+});

Diff for: lib/provider/image/jimp-image-processor.class.ts

@@ -17,11 +17,13 @@ export default class implements ImageProcessor {
         reject(
           `Query location out of bounds. Should be in range 0 <= x < image.width, is ${location.x}`
         );
+        return;
       }
       if (location.y < 0 || location.y >= img.height) {
         reject(
           `Query location out of bounds. Should be in range 0 <= y < image.height, is ${location.y}`
         );
+        return;
       }
       const jimpImage = imageToJimp(img);
       const rgba = Jimp.intToRGBA(