fix(abtest): resolve cross-PR review findings

.sampo/changesets/abtest-review-followup.md

@@ -0,0 +1,5 @@
+---
+npm/@listmonk-ops/abtest: patch
+---
+
+Fix unresolved review findings across Change Sets A-E: deep-clone locked hypotheses to prevent caller-mutation checksum invalidation, include revenue columns in reports when revenue_per_recipient is the primary metric, reject missing group keys in stratification, and remove dead duplicate validation.

packages/abtest/src/abtest-service.ts

@@ -206,7 +206,9 @@ export class AbTestService {
 										"Pre-locked hypothesis checksum verification failed; the metadata may have been tampered with",
 									);
 								}
-								return config.hypothesis!;
+								// Deep-clone so the stored test's hypothesis is
+								// detached from the caller's config object.
+								return structuredClone(config.hypothesis!);
 							})()
 						: lockHypothesis(config.hypothesis)
 					: undefined,

packages/abtest/src/hypothesis.ts

@@ -272,11 +272,6 @@ export function validateHypothesisMetadata(
 				"experimentScope.experimentFamilyKey must be a non-empty string",
 			);
 		}
-		if (!scope.experimentFamilyKey || scope.experimentFamilyKey.trim().length === 0) {
-			throw new HypothesisValidationError(
-				"experimentScope.experimentFamilyKey must be a non-empty string",
-			);
-		}
 		// Reject delimiter-only and empty-segment keys (".", "foo.", "foo..bar")
 		// by requiring one or more alphanumeric segments joined by single
 		// separators from [._-].
@@ -379,7 +374,11 @@ export function lockHypothesis(
 		);
 	}
 	const checksum = computeHypothesisChecksum(metadata);
-	return { ...metadata, lockedAt, checksum };
+	// Deep-clone so nested objects (primaryMetric, expectedLift, owner,
+	// experimentScope) are detached from the caller's references. This
+	// prevents post-lock mutation of the caller's object from silently
+	// invalidating the stored checksum.
+	return structuredClone({ ...metadata, lockedAt, checksum });
 }
 
 /**

packages/abtest/src/report.ts

@@ -46,6 +46,8 @@ export interface ExperimentReport {
 		clickRate: number;
 		conversionRate: number;
 		openRate: number;
+		revenue?: number;
+		revenuePerRecipient?: number;
 	}>;
 	srmPassed?: boolean;
 	srmPValue?: number;
@@ -116,6 +118,11 @@ export function buildExperimentReport(
 			clickRate: r.clickRate,
 			conversionRate: r.conversionRate,
 			openRate: r.openRate,
+			revenue: r.revenue,
+			revenuePerRecipient:
+				r.revenue !== undefined && r.sampleSize > 0
+					? r.revenue / r.sampleSize
+					: undefined,
 		};
 	});
 
@@ -258,12 +265,34 @@ export function reportToMarkdown(report: ExperimentReport): string {
 
 	lines.push("## Variant Results");
 	lines.push("");
-	lines.push("| Variant | Sample | Open Rate | Click Rate | Conversion Rate |");
-	lines.push("|---------|--------|-----------|------------|-----------------|");
+	const hasRevenue = report.variants.some((v) => v.revenue !== undefined);
+	const headers = [
+		"Variant",
+		"Sample",
+		"Open Rate",
+		"Click Rate",
+		"Conversion Rate",
+	];
+	if (hasRevenue) {
+		headers.push("Revenue", "Rev/Recipient");
+	}
+	lines.push(`| ${headers.join(" | ")} |`);
+	lines.push(`|${headers.map(() => "---------").join("|")}|`);
 	for (const v of report.variants) {
-		lines.push(
-			`| ${v.variantName} | ${v.sampleSize} | ${v.openRate.toFixed(2)}% | ${v.clickRate.toFixed(2)}% | ${v.conversionRate.toFixed(2)}% |`,
-		);
+		const cells = [
+			v.variantName,
+			String(v.sampleSize),
+			`${v.openRate.toFixed(2)}%`,
+			`${v.clickRate.toFixed(2)}%`,
+			`${v.conversionRate.toFixed(2)}%`,
+		];
+		if (hasRevenue) {
+			cells.push(
+				v.revenue?.toFixed(2) ?? "N/A",
+				v.revenuePerRecipient?.toFixed(4) ?? "N/A",
+			);
+		}
+		lines.push(`| ${cells.join(" | ")} |`);
 	}
 	lines.push("");
 

packages/abtest/src/stratification.ts

@@ -219,7 +219,12 @@ export function computeStratifiedQuotas(params: {
 			[];
 
 		for (const [index, groupKey] of groupOrder.entries()) {
-			const exactCount = groupExactCounts[groupKey] ?? 0;
+			const exactCount = groupExactCounts[groupKey];
+			if (exactCount === undefined) {
+				throw new Error(
+					`Stratified quota invariant: group "${groupKey}" is in groupOrder but missing from groupExactCounts`,
+				);
+			}
 			const ideal = (stratumSize * exactCount) / totalAudience;
 			ideals.push({ groupKey, ideal, index });
 			rowQuotas[groupKey] = Math.floor(ideal);