chore(update Freibetraege for 2024) (#1533)

* simplify freibetrag interface(s)

* update freibetraege for 2024, use year map for ease of updating, replace magic strings and update tests

* update unit test to ensure fallback works, regardless of whatever the actual, current year is

* add const for simplified child allowance

app/domains/beratungshilfe/vorabcheck/__test__/freibetrag.test.ts

@@ -1,157 +1,192 @@
 import {
-  freibetrag,
+  BASE_ALLOWANCE,
+  calculateFreibetrag,
+  freibetraegePerYear,
+  getFreibetraege,
   getVerfuegbaresEinkommenFreibetrag,
+  latestFreibetraegeYear,
+  SIMPLIFIED_CHILD_ALLOWANCE,
 } from "~/domains/beratungshilfe/vorabcheck/freibetrag";
+import { today } from "~/util/date";
 
-describe("freibetrag", () => {
-  it("should return 572 when single not working", () => {
+const { incomeAllowance, partnerAllowance, childrenBelow6Allowance } =
+  getFreibetraege(today().getFullYear());
+
+vi.spyOn(console, "warn");
+
+describe("getFreibetraege", () => {
+  it(`returns Freibetraege for ${latestFreibetraegeYear}`, () => {
+    expect(getFreibetraege(latestFreibetraegeYear)).toEqual(
+      freibetraegePerYear[latestFreibetraegeYear],
+    );
+  });
+
+  it("returns Freibetraege for the last valid year if current year is not found, and shows the user a warning", () => {
+    const nonExistentYear = latestFreibetraegeYear + 1;
+    const freibetraege = getFreibetraege(nonExistentYear);
+    // eslint-disable-next-line no-console
+    expect(console.warn).toHaveBeenCalledWith(
+      `No Freibeträge for year ${nonExistentYear}, using last valid Freibeträge from ${latestFreibetraegeYear}`,
+    );
+    expect(freibetraege).toEqual(freibetraegePerYear[latestFreibetraegeYear]);
+  });
+});
+
+describe("calculateFreibetrag", () => {
+  // Need values in cents
+  const baseAllowanceCents = BASE_ALLOWANCE * 100;
+  const incomeAllowanceCents = incomeAllowance * 100;
+  const partnerAllowanceCents = partnerAllowance * 100;
+  const childrenBelow6AllowanceCents = childrenBelow6Allowance * 100;
+
+  it(`should return ${baseAllowanceCents} when single not working`, () => {
     expect(
-      freibetrag({
+      calculateFreibetrag({
         working: false,
         partnership: false,
       }),
-    ).toEqual(57200);
+    ).toEqual(baseAllowanceCents);
   });
 
-  it("should return 572 + 251 when single working", () => {
+  it(`should return ${baseAllowanceCents} + ${incomeAllowanceCents} when single working`, () => {
     expect(
-      freibetrag({
+      calculateFreibetrag({
         working: true,
         partnership: false,
       }),
-    ).toEqual(57200 + 25100);
+    ).toEqual(baseAllowanceCents + incomeAllowanceCents);
   });
 
-  it("should return 572 + 552 when partner not working", () => {
+  it(`should return ${baseAllowanceCents} + ${partnerAllowanceCents} when partner not working`, () => {
     expect(
-      freibetrag({
+      calculateFreibetrag({
         working: false,
         partnership: true,
       }),
-    ).toEqual(57200 + 55200);
+    ).toEqual(baseAllowanceCents + partnerAllowanceCents);
   });
 
-  it("should return 572 + 552 - partner income when partner working smaller than 552", () => {
+  it(`should return ${baseAllowanceCents} + ${partnerAllowanceCents} - partner income when partner working smaller than ${partnerAllowanceCents}`, () => {
     expect(
-      freibetrag({
+      calculateFreibetrag({
         working: false,
         partnership: true,
         partnerIncome: 50000,
       }),
-    ).toEqual(57200 + 55200 - 50000);
+    ).toEqual(baseAllowanceCents + partnerAllowanceCents - 50000);
   });
 
-  it("should return 572 when partner working bigger than 552", () => {
+  it(`should return ${baseAllowanceCents} when partner working bigger than ${partnerAllowanceCents}`, () => {
     expect(
-      freibetrag({
+      calculateFreibetrag({
         working: false,
         partnership: true,
         partnerIncome: 80000,
       }),
-    ).toEqual(57200);
+    ).toEqual(baseAllowanceCents);
   });
 
-  it("should return 572 + 350 when 1 child 0-6 not working", () => {
+  it(`should return ${baseAllowanceCents} + ${childrenBelow6AllowanceCents} when 1 child 0-6 not working`, () => {
     expect(
-      freibetrag({
+      calculateFreibetrag({
         childrenBelow6: 1,
       }),
-    ).toEqual(57200 + 35000);
+    ).toEqual(baseAllowanceCents + childrenBelow6AllowanceCents);
   });
 
-  it("should return 572 + 2*350 when 2 children 0-6 not working", () => {
+  it(`should return ${baseAllowanceCents} + 2*${childrenBelow6AllowanceCents} when 2 children 0-6 not working`, () => {
     expect(
-      freibetrag({
+      calculateFreibetrag({
         childrenBelow6: 2,
       }),
-    ).toEqual(57200 + 2 * 35000);
+    ).toEqual(baseAllowanceCents + 2 * childrenBelow6AllowanceCents);
   });
 
-  it("should return 572 + 350 - child income when 1 child 0-6 working less than 350", () => {
+  it(`should return ${baseAllowanceCents} + ${childrenBelow6AllowanceCents} - child income when 1 child 0-6 working less than ${childrenBelow6AllowanceCents}`, () => {
     expect(
-      freibetrag({
+      calculateFreibetrag({
         childrenBelow6: 1,
         childrenIncome: 10000,
       }),
-    ).toEqual(57200 + 35000 - 10000);
+    ).toEqual(baseAllowanceCents + childrenBelow6AllowanceCents - 10000);
   });
 
-  it("should return 572 when 1 child 0-6 working more than 350", () => {
+  it(`should return ${baseAllowanceCents} when 1 child 0-6 working more than ${childrenBelow6AllowanceCents}`, () => {
     expect(
-      freibetrag({
+      calculateFreibetrag({
         childrenBelow6: 1,
         childrenIncome: 80000,
       }),
-    ).toEqual(57200);
+    ).toEqual(baseAllowanceCents);
   });
 
-  it("should return 572 + 2*350 - children income when 2 children 0-6 working less than 350", () => {
+  it(`should return ${baseAllowanceCents} + 2*${childrenBelow6AllowanceCents} - children income when 2 children 0-6 working less than ${childrenBelow6AllowanceCents}`, () => {
     expect(
-      freibetrag({
+      calculateFreibetrag({
         childrenBelow6: 2,
         childrenIncome: 10000,
       }),
-    ).toEqual(57200 + 2 * 35000 - 10000);
+    ).toEqual(baseAllowanceCents + 2 * childrenBelow6AllowanceCents - 10000);
   });
 
-  it("should return 572 + 2*350 - children income when 2 children 0-6 working more than 350 less than 2*350", () => {
+  it(`should return ${baseAllowanceCents} + 2*${childrenBelow6AllowanceCents} - children income when 2 children 0-6 working more than ${childrenBelow6AllowanceCents} less than 2*${childrenBelow6AllowanceCents}`, () => {
     expect(
-      freibetrag({
+      calculateFreibetrag({
         childrenBelow6: 2,
         childrenIncome: 50000,
       }),
-    ).toEqual(57200 + 2 * 35000 - 50000);
+    ).toEqual(baseAllowanceCents + 2 * childrenBelow6AllowanceCents - 50000);
   });
 
-  it("should handle NaN children as zero children", () => {
+  it("should handle undefined children as zero children", () => {
     expect(
-      freibetrag({
-        childrenBelow6: NaN,
+      calculateFreibetrag({
+        childrenBelow6: undefined,
       }),
-    ).toEqual(57200);
+    ).toEqual(baseAllowanceCents);
   });
 });
 
 const cases = [
   {
     condition: "empty context",
     context: {},
-    result: 572,
+    result: BASE_ALLOWANCE,
   },
   {
     condition: "partner",
     context: { partnerschaft: "yes" },
-    result: 572 + 552,
+    result: BASE_ALLOWANCE + partnerAllowance,
   },
   {
     condition: "partner and no kid but kinderAnzahlKurz given",
     context: { partnerschaft: "yes", kinderAnzahlKurz: "1" },
-    result: 572 + 552,
+    result: BASE_ALLOWANCE + partnerAllowance,
   },
   {
     condition: "partner and one kid",
     context: { partnerschaft: "yes", kinderKurz: "yes", kinderAnzahlKurz: "1" },
-    result: 572 + 552 + 400,
+    result: BASE_ALLOWANCE + partnerAllowance + SIMPLIFIED_CHILD_ALLOWANCE,
   },
   {
     condition: "no partner and one kid",
     context: { partnerschaft: "no", kinderKurz: "yes", kinderAnzahlKurz: "1" },
-    result: 572 + 400,
+    result: BASE_ALLOWANCE + SIMPLIFIED_CHILD_ALLOWANCE,
   },
   {
     condition: "no partner and three kids",
     context: { partnerschaft: "no", kinderKurz: "yes", kinderAnzahlKurz: "3" },
-    result: 572 + 3 * 400,
+    result: BASE_ALLOWANCE + 3 * SIMPLIFIED_CHILD_ALLOWANCE,
   },
   {
     condition: "erwerbstaetig",
     context: { erwerbstaetigkeit: "yes" },
-    result: 572 + 251,
+    result: BASE_ALLOWANCE + incomeAllowance,
   },
   {
     condition: "partner and erwerbstaetig",
     context: { partnerschaft: "yes", erwerbstaetigkeit: "yes" },
-    result: 572 + 552 + 251,
+    result: BASE_ALLOWANCE + partnerAllowance + incomeAllowance,
   },
   {
     condition: "partner and erwerbstaetig and two kids",
@@ -161,7 +196,11 @@ const cases = [
       kinderKurz: "yes",
       kinderAnzahlKurz: "2",
     },
-    result: 572 + 552 + 251 + 2 * 400,
+    result:
+      BASE_ALLOWANCE +
+      partnerAllowance +
+      incomeAllowance +
+      2 * SIMPLIFIED_CHILD_ALLOWANCE,
   },
 ] as const;
 

app/domains/beratungshilfe/vorabcheck/freibetrag.ts

@@ -1,6 +1,64 @@
+import mapValues from "lodash/mapValues";
+import { today } from "~/util/date";
 import { type AllContexts } from "../../common";
 
-export function freibetrag({
+type Freibetraege = {
+  incomeAllowance: number;
+  partnerAllowance: number;
+  dependentAdultAllowance: number;
+  children15To18Allowance: number;
+  children7To14Allowance: number;
+  childrenBelow6Allowance: number;
+};
+
+export const BASE_ALLOWANCE = 572;
+export const SIMPLIFIED_CHILD_ALLOWANCE = 400;
+export const freibetraegePerYear: Record<number, Freibetraege> = {
+  2023: {
+    incomeAllowance: 251,
+    partnerAllowance: 552,
+    dependentAdultAllowance: 442,
+    children15To18Allowance: 462,
+    children7To14Allowance: 383,
+    childrenBelow6Allowance: 350,
+  },
+  2024: {
+    incomeAllowance: 282,
+    partnerAllowance: 619,
+    dependentAdultAllowance: 496,
+    children15To18Allowance: 518,
+    children7To14Allowance: 429,
+    childrenBelow6Allowance: 393,
+  },
+};
+export const latestFreibetraegeYear = Math.max(
+  ...Object.keys(freibetraegePerYear).map((year) => Number(year)),
+);
+
+export function getFreibetraege(year: number) {
+  const freibetraege = freibetraegePerYear[year];
+  if (!freibetraege) {
+    // eslint-disable-next-line no-console
+    console.warn(
+      `No Freibeträge for year ${year}, using last valid Freibeträge from ${latestFreibetraegeYear}`,
+    );
+    return freibetraegePerYear[latestFreibetraegeYear];
+  }
+  return freibetraege;
+}
+
+type CalculateFreibetragProps = {
+  working: boolean;
+  partnership: boolean;
+  partnerIncome: number;
+  childrenBelow6: number;
+  children7To14: number;
+  children15To18: number;
+  childrenAbove18: number;
+  childrenIncome: number;
+};
+
+export function calculateFreibetrag({
   working,
   partnership,
   partnerIncome,
@@ -9,48 +67,49 @@ export function freibetrag({
   children15To18,
   childrenAbove18,
   childrenIncome,
-}: {
-  working?: boolean;
-  partnership?: boolean;
-  partnerIncome?: number;
-  childrenBelow6?: number;
-  children7To14?: number;
-  children15To18?: number;
-  childrenAbove18?: number;
-  childrenIncome?: number;
-}): number {
-  let betrag = 57200;
+}: Partial<CalculateFreibetragProps>): number {
+  let betrag = BASE_ALLOWANCE * 100;
+  const {
+    incomeAllowance,
+    partnerAllowance,
+    dependentAdultAllowance,
+    children15To18Allowance,
+    children7To14Allowance,
+    childrenBelow6Allowance,
+  } = mapValues(getFreibetraege(today().getFullYear()), (v) => v * 100);
 
   if (working) {
-    betrag += 25100;
+    betrag += incomeAllowance;
   }
 
   if (partnership) {
-    betrag += Math.max(55200 - (partnerIncome ?? 0), 0);
+    betrag += Math.max(partnerAllowance - (partnerIncome ?? 0), 0);
   }
 
   const childrenFreibetrag =
-    (Number.isNaN(childrenBelow6) ? 0 : (childrenBelow6 ?? 0)) * 35000 +
-    (Number.isNaN(children7To14) ? 0 : (children7To14 ?? 0)) * 38300 +
-    (Number.isNaN(children15To18) ? 0 : (children15To18 ?? 0)) * 46200 +
-    (Number.isNaN(childrenAbove18) ? 0 : (childrenAbove18 ?? 0)) * 44200;
+    (childrenBelow6 ? childrenBelow6 * childrenBelow6Allowance : 0) +
+    (children7To14 ? children7To14 * children7To14Allowance : 0) +
+    (children15To18 ? children15To18 * children15To18Allowance : 0) +
+    (childrenAbove18 ? childrenAbove18 * dependentAdultAllowance : 0);
 
   betrag += Math.max(childrenFreibetrag - (childrenIncome ?? 0), 0);
 
   return betrag;
 }
 
 function freibetragShort(
-  working?: boolean,
-  partnership?: boolean,
-  childrenCount?: number,
+  working: boolean,
+  partnership: boolean,
+  childrenCount: number,
 ): number {
-  const betrag = 552 + 20;
+  const { partnerAllowance, incomeAllowance } = getFreibetraege(
+    today().getFullYear(),
+  );
   return (
-    betrag +
-    (working ? 251 : 0) +
-    (partnership ? 552 : 0) +
-    (childrenCount ? childrenCount * 400 : 0)
+    BASE_ALLOWANCE +
+    (working ? incomeAllowance : 0) +
+    (partnership ? partnerAllowance : 0) +
+    (childrenCount ? childrenCount * SIMPLIFIED_CHILD_ALLOWANCE : 0)
   );
 }