add tests for helper functions on bar

component/bar.tsx

@@ -39,10 +39,10 @@ export const Bar: React.FC<BarProps> = ({
 
   return (
     <Path
-    key={`bar-${barNumber}-${index}`}
-    d={drawBarPath(xOrigin, yOrigin, barWidth, height, roundedRadius)}
-    fill={fill}
-    testID={`bar-${barNumber}-${index}`}
+      key={`bar-path-${barNumber}-${index}`}
+      d={drawBarPath(xOrigin, yOrigin, barWidth, height, roundedRadius)}
+      fill={fill}
+      testID={`bar-${barNumber}-${index}`}
     />
   );
 };

component/custom-bars.tsx

@@ -21,7 +21,7 @@ interface CustomBarsProps {
   roundedRadius: number;
 }
 
-export const CustomBars: React.FC<Partial<CustomBarsProps>> = ({
+export const CustomBars: React.FC<CustomBarsProps> = ({
   x: scaleX,
   y: scaleY,
   bandwidth,