From 03c5f2538ff2dd55392213a013ac58b60586fe93 Mon Sep 17 00:00:00 2001
From: medic-bot <medic-bot@lacompagniemaximus.com>
Date: Wed, 11 Mar 2026 13:02:47 -0400
Subject: [PATCH] refactor: inline buildPrevYearTotalMap and remove
 disproportionate tests (#39)

The 3-line helper was exported solely for testing. Inlining it removes the
export-for-test pattern and eliminates 50 lines of tests that were
disproportionate for a trivial filter-and-set loop.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 src/hooks/useBudget.test.ts | 50 -------------------------------------
 src/hooks/useBudget.ts      | 21 ++++------------
 2 files changed, 5 insertions(+), 66 deletions(-)
 delete mode 100644 src/hooks/useBudget.test.ts

diff --git a/src/hooks/useBudget.test.ts b/src/hooks/useBudget.test.ts
deleted file mode 100644
index 220b684..0000000
--- a/src/hooks/useBudget.test.ts
+++ /dev/null
@@ -1,50 +0,0 @@
-import { describe, it, expect } from "vitest";
-import { buildPrevYearTotalMap } from "./useBudget";
-
-/**
- * Unit tests for the previous-year actuals normalization logic used in useBudget.
- *
- * Transaction amounts in the database use signed values (expenses are negative,
- * income is positive). The buildPrevYearTotalMap function preserves these signs
- * as-is, because the budget display layer does NOT apply a sign multiplier to
- * previous year actuals (unlike planned budget amounts).
- */
-
-describe("buildPrevYearTotalMap", () => {
-  it("should preserve negative sign for expense actuals", () => {
-    const actuals = [{ category_id: 1, actual: -500 }]; // expense: negative in DB
-    const map = buildPrevYearTotalMap(actuals);
-    expect(map.get(1)).toBe(-500);
-  });
-
-  it("should preserve positive sign for income actuals", () => {
-    const actuals = [{ category_id: 2, actual: 3000 }]; // income: positive in DB
-    const map = buildPrevYearTotalMap(actuals);
-    expect(map.get(2)).toBe(3000);
-  });
-
-  it("should skip null category_id entries", () => {
-    const actuals = [{ category_id: null, actual: -100 }];
-    const map = buildPrevYearTotalMap(actuals);
-    expect(map.size).toBe(0);
-  });
-
-  it("should handle zero actuals", () => {
-    const actuals = [{ category_id: 3, actual: 0 }];
-    const map = buildPrevYearTotalMap(actuals);
-    expect(map.get(3)).toBe(0);
-  });
-
-  it("should handle multiple categories", () => {
-    const actuals = [
-      { category_id: 1, actual: -200 },
-      { category_id: 2, actual: 1500 },
-      { category_id: 3, actual: -75.5 },
-    ];
-    const map = buildPrevYearTotalMap(actuals);
-    expect(map.size).toBe(3);
-    expect(map.get(1)).toBe(-200);
-    expect(map.get(2)).toBe(1500);
-    expect(map.get(3)).toBe(-75.5);
-  });
-});
diff --git a/src/hooks/useBudget.ts b/src/hooks/useBudget.ts
index 2f41eab..bdd0038 100644
--- a/src/hooks/useBudget.ts
+++ b/src/hooks/useBudget.ts
@@ -63,21 +63,6 @@ function reducer(state: BudgetState, action: BudgetAction): BudgetState {
 
 const TYPE_ORDER: Record<string, number> = { expense: 0, income: 1, transfer: 2 };
 
-/**
- * Build a map of category_id -> annual actual total from raw actuals.
- * Transaction amounts are already signed (expenses negative, income positive),
- * so they are stored as-is without normalization.
- */
-export function buildPrevYearTotalMap(
-  actuals: Array<{ category_id: number | null; actual: number }>
-): Map<number, number> {
-  const prevYearTotalMap = new Map<number, number>();
-  for (const a of actuals) {
-    if (a.category_id != null) prevYearTotalMap.set(a.category_id, a.actual);
-  }
-  return prevYearTotalMap;
-}
-
 export function useBudget() {
   const [state, dispatch] = useReducer(reducer, undefined, initialState);
   const fetchIdRef = useRef(0);
@@ -105,7 +90,11 @@ export function useBudget() {
       }
 
       // Build a map for previous year actuals: categoryId -> annual actual total
-      const prevYearTotalMap = buildPrevYearTotalMap(prevYearActuals);
+      // Amounts are already signed (expenses negative, income positive) — stored as-is.
+      const prevYearTotalMap = new Map<number, number>();
+      for (const a of prevYearActuals) {
+        if (a.category_id != null) prevYearTotalMap.set(a.category_id, a.actual);
+      }
 
       // Helper: build months array from entryMap
       const buildMonths = (catId: number) => {