Be consistent with calc utils

bin/plugin/commands/performance.js

@@ -47,14 +47,18 @@ function sanitizeBranchName( branch ) {
  *
  * @param {number[]} array
  *
- * @return {number} Median.
+ * @return {number|undefined} Median value or undefined if array empty.
  */
-function median( array ) {
-	const mid = Math.floor( array.length / 2 ),
-		numbers = [ ...array ].sort( ( a, b ) => a - b );
-	return array.length % 2 !== 0
-		? numbers[ mid ]
-		: ( numbers[ mid - 1 ] + numbers[ mid ] ) / 2;
+export function median( array ) {
+	if ( array.length === 0 ) return undefined;
+
+	const numbers = [ ...array ].sort( ( a, b ) => a - b );
+	const middleIndex = Math.floor( numbers.length / 2 );
+
+	if ( numbers.length % 2 === 0 ) {
+		return ( numbers[ middleIndex - 1 ] + numbers[ middleIndex ] ) / 2;
+	}
+	return numbers[ middleIndex ];
 }
 
 /**
@@ -355,10 +359,14 @@ async function runPerformanceTests( branches, options ) {
 			results[ testSuite ][ branch ] = {};
 
 			for ( const metric of metrics ) {
-				// @ts-ignore
-				const values = resultsRounds.map( ( item ) => item[ metric ] );
-				// @ts-ignore
-				results[ testSuite ][ branch ][ metric ] = median( values );
+				const values = resultsRounds
+					.map( ( round ) => round[ metric ] )
+					.filter( ( value ) => typeof value === 'number' );
+
+				const medianValue = median( values );
+				if ( medianValue !== undefined ) {
+					results[ testSuite ][ branch ][ metric ] = medianValue;
+				}
 			}
 		}
 

test/performance/config/performance-reporter.ts

@@ -13,7 +13,7 @@ import type {
 /**
  * Internal dependencies
  */
-import { average, median, formatTime } from '../utils';
+import { average, median, minimum, maximum, round } from '../utils';
 
 export interface WPRawPerformanceResults {
 	timeToFirstByte: number[];
@@ -96,32 +96,32 @@ export function curateResults(
 			firstContentfulPaint: average( results.firstContentfulPaint ),
 			firstBlock: average( results.firstBlock ),
 			type: average( results.type ),
-			minType: Math.min( ...results.type ),
-			maxType: Math.max( ...results.type ),
+			minType: minimum( results.type ),
+			maxType: maximum( results.type ),
 			typeContainer: average( results.typeContainer ),
-			minTypeContainer: Math.min( ...results.typeContainer ),
-			maxTypeContainer: Math.max( ...results.typeContainer ),
+			minTypeContainer: minimum( results.typeContainer ),
+			maxTypeContainer: maximum( results.typeContainer ),
 			focus: average( results.focus ),
-			minFocus: Math.min( ...results.focus ),
-			maxFocus: Math.max( ...results.focus ),
+			minFocus: minimum( results.focus ),
+			maxFocus: maximum( results.focus ),
 			inserterOpen: average( results.inserterOpen ),
-			minInserterOpen: Math.min( ...results.inserterOpen ),
-			maxInserterOpen: Math.max( ...results.inserterOpen ),
+			minInserterOpen: minimum( results.inserterOpen ),
+			maxInserterOpen: maximum( results.inserterOpen ),
 			inserterSearch: average( results.inserterSearch ),
-			minInserterSearch: Math.min( ...results.inserterSearch ),
-			maxInserterSearch: Math.max( ...results.inserterSearch ),
+			minInserterSearch: minimum( results.inserterSearch ),
+			maxInserterSearch: maximum( results.inserterSearch ),
 			inserterHover: average( results.inserterHover ),
-			minInserterHover: Math.min( ...results.inserterHover ),
-			maxInserterHover: Math.max( ...results.inserterHover ),
+			minInserterHover: minimum( results.inserterHover ),
+			maxInserterHover: maximum( results.inserterHover ),
 			listViewOpen: average( results.listViewOpen ),
-			minListViewOpen: Math.min( ...results.listViewOpen ),
-			maxListViewOpen: Math.max( ...results.listViewOpen ),
+			minListViewOpen: minimum( results.listViewOpen ),
+			maxListViewOpen: maximum( results.listViewOpen ),
 		};
 	}
 
 	return Object.fromEntries(
 		Object.entries( output ).map( ( [ key, value ] ) => {
-			return [ key, formatTime( value ) ];
+			return [ key, round( value ) ];
 		} )
 	);
 }
@@ -188,7 +188,7 @@ class PerformanceReporter implements Reporter {
 			const printableResults: Record< string, { value: string } > = {};
 
 			for ( const [ key, value ] of Object.entries( results ) ) {
-				if ( isFinite( value ) ) {
+				if ( typeof value === 'number' ) {
 					printableResults[ key ] = { value: `${ value } ms` };
 				}
 			}

test/performance/utils.js

@@ -4,6 +4,48 @@
 import path from 'path';
 import { existsSync, readFileSync, unlinkSync } from 'fs';
 
+export function sum( array ) {
+	if ( array.length === 0 ) return undefined;
+
+	return array.reduce( ( a, b ) => a + b, 0 );
+}
+
+export function average( array ) {
+	if ( array.length === 0 ) return undefined;
+
+	return sum( array ) / array.length;
+}
+
+export function median( array ) {
+	if ( array.length === 0 ) return undefined;
+
+	const numbers = [ ...array ].sort( ( a, b ) => a - b );
+	const middleIndex = Math.floor( numbers.length / 2 );
+
+	if ( numbers.length % 2 === 0 ) {
+		return ( numbers[ middleIndex - 1 ] + numbers[ middleIndex ] ) / 2;
+	}
+	return numbers[ middleIndex ];
+}
+
+export function minimum( array ) {
+	if ( array.length === 0 ) return undefined;
+
+	return Math.min( ...array );
+}
+
+export function maximum( array ) {
+	if ( array.length === 0 ) return undefined;
+
+	return Math.max( ...array );
+}
+
+export function round( number, decimalPlaces = 2 ) {
+	const factor = Math.pow( 10, decimalPlaces );
+
+	return Math.round( number * factor ) / factor;
+}
+
 export function readFile( filePath ) {
 	if ( ! existsSync( filePath ) ) {
 		throw new Error( `File does not exist: ${ filePath }` );
@@ -128,39 +170,6 @@ export async function getLoadingDurations( page ) {
 	} );
 }
 
-export function sum( arr ) {
-	return arr.reduce( ( a, b ) => a + b, 0 );
-}
-
-export function average( array ) {
-	return array.reduce( ( a, b ) => a + b, 0 ) / array.length;
-}
-
-export function median( array ) {
-	const mid = Math.floor( array.length / 2 ),
-		numbers = [ ...array ].sort( ( a, b ) => a - b );
-	return array.length % 2 !== 0
-		? numbers[ mid ]
-		: ( numbers[ mid - 1 ] + numbers[ mid ] ) / 2;
-}
-
-export function round( number, decimalPlaces = 2 ) {
-	const factor = Math.pow( 10, decimalPlaces );
-	return Math.round( number * factor ) / factor;
-}
-
-/**
- * Rounds and format a time passed in milliseconds.
- *
- * @param {number} number
- *
- * @return {number} Formatted time.
- */
-export function formatTime( number ) {
-	const factor = Math.pow( 10, 2 );
-	return Math.round( number * factor ) / factor;
-}
-
 export async function loadBlocksFromHtml( page, filepath ) {
 	if ( ! existsSync( filepath ) ) {
 		throw new Error( `File not found (${ filepath })` );