JSONbored · philluiz2323 · Jul 26, 2026
@@ -45,13 +45,16 @@ export function trendHasAnySignal(weeks: SlopDuplicateTrendWeek[]): boolean {
   return seriesHasSignal(weeks, "slop") || seriesHasSignal(weeks, "duplicate");
 }
 
+/** Most recent week with a non-null value for the given series (independent per series). */
 export function latestWeekWithSignal(
   weeks: SlopDuplicateTrendWeek[],
+  series: "slop" | "duplicate",
 ): SlopDuplicateTrendWeek | null {
   for (let index = weeks.length - 1; index >= 0; index -= 1) {
     const week = weeks[index];
     if (!week) continue;
-    if (week.slopFlagRatePct !== null || week.duplicateFlagRatePct !== null) return week;
+    const value = series === "slop" ? week.slopFlagRatePct : week.duplicateFlagRatePct;
+    if (value !== null) return week;
   }
   return null;
 }

@@ -2,7 +2,10 @@ import { render, screen } from "@testing-library/react";
 import { describe, expect, it } from "vitest";
 
 import { SlopDuplicateTrendCard } from "@/components/site/app-panels/slop-duplicate-trend-card";
-import type { MaintainerSlopDuplicateTrend } from "@/components/site/app-panels/slop-duplicate-trend-card-model";
+import {
+  latestWeekWithSignal,
+  type MaintainerSlopDuplicateTrend,
+} from "@/components/site/app-panels/slop-duplicate-trend-card-model";
 
 function trend(
   overrides: Partial<MaintainerSlopDuplicateTrend> = {},
@@ -86,4 +89,30 @@ describe("SlopDuplicateTrendCard", () => {
     render(<SlopDuplicateTrendCard trend={trend({ stale: true })} />);
     expect(screen.getByText(/stale snapshot/i)).toBeTruthy();
   });
+
+  it("resolves each series' legend from its own latest signal-bearing week", () => {
+    // Most recent week has only duplicate signal; earlier week has slop (and band).
+    // Shared "latest any signal" would hide the slop band behind the null series.
+    const weeks = [
+      {
+        weekStart: "2026-06-02",
+        slopFlagRatePct: 18.5,
+        slopBandLabel: "elevated" as const,
+        duplicateFlagRatePct: null,
+      },
+      {
+        weekStart: "2026-06-09",
+        slopFlagRatePct: null,
+        slopBandLabel: null,
+        duplicateFlagRatePct: 40,
+      },
+    ];
+
+    expect(latestWeekWithSignal(weeks, "slop")?.weekStart).toBe("2026-06-02");
+    expect(latestWeekWithSignal(weeks, "duplicate")?.weekStart).toBe("2026-06-09");
+
+    render(<SlopDuplicateTrendCard trend={trend({ weeks })} />);
+    expect(screen.getByText(/latest band: elevated/i)).toBeTruthy();
+    expect(screen.getByText(/latest: 40%/i)).toBeTruthy();
+  });
 });
@@ -26,7 +26,8 @@ export function SlopDuplicateTrendCard({ trend }: { trend: MaintainerSlopDuplica
   const hasSignal = trendHasAnySignal(trend.weeks);
   const hasSlop = seriesHasSignal(trend.weeks, "slop");
   const hasDuplicate = seriesHasSignal(trend.weeks, "duplicate");
-  const latest = latestWeekWithSignal(trend.weeks);
+  const latestSlop = latestWeekWithSignal(trend.weeks, "slop");
+  const latestDuplicate = latestWeekWithSignal(trend.weeks, "duplicate");
 
   return (
     <AnalyticsCardShell
@@ -51,20 +52,20 @@ export function SlopDuplicateTrendCard({ trend }: { trend: MaintainerSlopDuplica
           color="var(--mint)"
           label="Slop flag rate"
           detail={
-            latest?.slopBandLabel
-              ? `latest band: ${latest.slopBandLabel}`
+            latestSlop?.slopBandLabel
+              ? `latest band: ${latestSlop.slopBandLabel}`
               : hasSlop
-                ? `latest: ${formatTrendRatePct(latest?.slopFlagRatePct)}`
+                ? `latest: ${formatTrendRatePct(latestSlop?.slopFlagRatePct)}`
                 : "no slop samples"
           }
-          bandLabel={latest?.slopBandLabel}
+          bandLabel={latestSlop?.slopBandLabel}
         />
         <LegendItem
           color="var(--warning)"
           label="Duplicate flag rate"
           detail={
             hasDuplicate
-              ? `latest: ${formatTrendRatePct(latest?.duplicateFlagRatePct)}`
+              ? `latest: ${formatTrendRatePct(latestDuplicate?.duplicateFlagRatePct)}`
               : "no duplicate samples"
           }
         />