fixup! feat: add t-test mode for statistical significance testing

Author: RafaelGSS

README.md

@@ -726,8 +726,8 @@ Example output:
 ```
 T-Test Mode: Enabled (repeatSuite=30)
 
-baseline   x 1,234,567 ops/sec (300 runs sampled) min..max=(...)
-optimized  x 9,876,543 ops/sec (305 runs sampled) min..max=(...)
+baseline   x 1,234,567 ops/sec (300 runs sampled) min..max=(810.05ns...812.45ns)
+optimized  x 9,876,543 ops/sec (305 runs sampled) min..max=(101.23ns...102.87ns)
 
 Summary (vs. baseline):
   baseline   (baseline)

lib/index.js

@@ -30,6 +30,7 @@ const {
 	validateString,
 	validateArray,
 	validateBenchmarkMode,
+	validateBoolean,
 } = require("./validators");
 const {
 	welchTTest,
@@ -152,7 +153,10 @@ class Suite {
 			printHeader: true,
 		};
 
-		this.#ttest = options.ttest || false;
+		if (options.ttest !== undefined) {
+			validateBoolean(options.ttest, "options.ttest");
+		}
+		this.#ttest = options.ttest ?? false;
 
 		let repeatSuite = defaultBenchOptions.repeatSuite;
 		if (options.repeatSuite !== undefined) {

lib/reporter/chart.js

@@ -130,10 +130,18 @@ function toChart(results, options = { labelWidth: 45, printHeader: true }) {
 		if (hasBaseline) {
 			if (result.baseline) {
 				comment = styleText("magenta", "(baseline)");
-			} else if (result.comparison.startsWith("-")) {
-				comment = styleText("red", `(${result.comparison.slice(1)}x slower)`);
 			} else {
-				comment = styleText("green", `(${result.comparison}x faster)`);
+				const isSignificant = result.significanceTest?.significant ?? true;
+				const isFaster = !result.comparison.startsWith("-");
+				const comparisonText = isFaster
+					? `(${result.comparison}x faster)`
+					: `(${result.comparison.slice(1)}x slower)`;
+
+				if (isSignificant) {
+					comment = styleText(isFaster ? "green" : "red", comparisonText);
+				} else {
+					comment = styleText("dim", comparisonText);
+				}
 			}
 		}
 

lib/reporter/pretty.js

@@ -74,10 +74,18 @@ function toPretty(results, options = {}) {
 
 			if (result.baseline) {
 				text += styleText("magenta", "(baseline)");
-			} else if (!result.comparison.startsWith("-")) {
-				text += styleText("green", `(${result.comparison}x faster)`);
 			} else {
-				text += styleText("red", `(${result.comparison.slice(1)}x slower)`);
+				const isSignificant = result.significanceTest?.significant ?? true;
+				const isFaster = !result.comparison.startsWith("-");
+				const comparisonText = isFaster
+					? `(${result.comparison}x faster)`
+					: `(${result.comparison.slice(1)}x slower)`;
+
+				if (isSignificant) {
+					text += styleText(isFaster ? "green" : "red", comparisonText);
+				} else {
+					text += styleText("dim", comparisonText);
+				}
 			}
 
 			if (result.significanceTest) {

lib/reporter/text.js

@@ -73,10 +73,16 @@ function toText(results, options = {}) {
 			if (result.baseline) {
 				text += styleText("magenta", "(baseline)");
 			} else if (result.comparison !== undefined) {
-				if (!result.comparison.startsWith("-")) {
-					text += styleText("green", `(${result.comparison}x faster)`);
+				const isSignificant = result.significanceTest?.significant ?? true;
+				const isFaster = !result.comparison.startsWith("-");
+				const comparisonText = isFaster
+					? `(${result.comparison}x faster)`
+					: `(${result.comparison.slice(1)}x slower)`;
+
+				if (isSignificant) {
+					text += styleText(isFaster ? "green" : "red", comparisonText);
 				} else {
-					text += styleText("red", `(${result.comparison.slice(1)}x slower)`);
+					text += styleText("dim", comparisonText);
 				}
 
 				if (result.significanceTest) {

lib/validators.js

@@ -121,11 +121,25 @@ function validateArray(value, name) {
 		);
 }
 
+/**
+ * Validates that a value is a boolean
+ * @param {any} value - The value to validate
+ * @param {string} name - Name of the parameter being validated
+ * @throws {Error} If validation fails
+ */
+function validateBoolean(value, name) {
+	if (typeof value !== "boolean")
+		throw ERR_INVALID_ARG_TYPE(
+			`value must be a boolean, name: ${name}, value: ${value}`,
+		);
+}
+
 module.exports = {
 	validateFunction,
 	validateNumber,
 	validateObject,
 	validateString,
 	validateArray,
 	validateBenchmarkMode,
+	validateBoolean,
 };