X-Git-Url: https://git.piment-noir.org/?a=blobdiff_plain;f=src%2Futils.ts;h=7ac4ab25db67446a49b2fc42a0f219c043d4af6f;hb=6d1d4d956de1d48e51517014bc0b4c276bbf876a;hp=46ab5051f38ff77eb2fd06c41199bd360b306276;hpb=78cea37e264d5ca527bc42eb056f3b9579a2b2c4;p=poolifier.git

diff --git a/src/utils.ts b/src/utils.ts
index 46ab5051..7ac4ab25 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -1,11 +1,97 @@
+import os from 'node:os'
+import type {
+  MeasurementStatisticsRequirements,
+  WorkerChoiceStrategyOptions
+} from './pools/selection-strategies/selection-strategies-types'
+
 /**
  * An intentional empty function.
  */
-export const EMPTY_FUNCTION: () => void = () => {
+export const EMPTY_FUNCTION: () => void = Object.freeze(() => {
   /* Intentionally empty */
+})
+
+/**
+ * Default worker choice strategy options.
+ */
+export const DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS: WorkerChoiceStrategyOptions =
+  {
+    runTime: { median: false },
+    waitTime: { median: false },
+    elu: { median: false }
+  }
+
+/**
+ * Default measurement statistics requirements.
+ */
+export const DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS: MeasurementStatisticsRequirements =
+  {
+    aggregate: false,
+    average: false,
+    median: false
+  }
+
+/**
+ * Returns safe host OS optimized estimate of the default amount of parallelism a pool should use.
+ * Always returns a value greater than zero.
+ *
+ * @returns The host OS optimized maximum pool size.
+ */
+export const availableParallelism = (): number => {
+  let availableParallelism = 1
+  try {
+    availableParallelism = os.availableParallelism()
+  } catch {
+    const cpus = os.cpus()
+    if (Array.isArray(cpus) && cpus.length > 0) {
+      availableParallelism = cpus.length
+    }
+  }
+  return availableParallelism
+}
+
+/**
+ * Computes the median of the given data set.
+ *
+ * @param dataSet - Data set.
+ * @returns The median of the given data set.
+ */
+export const median = (dataSet: number[]): number => {
+  if (Array.isArray(dataSet) && dataSet.length === 0) {
+    return 0
+  }
+  if (Array.isArray(dataSet) && dataSet.length === 1) {
+    return dataSet[0]
+  }
+  const sortedDataSet = dataSet.slice().sort((a, b) => a - b)
+  return (
+    (sortedDataSet[(sortedDataSet.length - 1) >> 1] +
+      sortedDataSet[sortedDataSet.length >> 1]) /
+    2
+  )
+}
+
+/**
+ * Rounds the given number to the given scale.
+ * The rounding is done using the "round half away from zero" method.
+ *
+ * @param num - The number to round.
+ * @param scale - The scale to round to.
+ * @returns The rounded number.
+ */
+export const round = (num: number, scale = 2): number => {
+  const rounder = Math.pow(10, scale)
+  return Math.round(num * rounder * (1 + Number.EPSILON)) / rounder
 }
 
 /**
- * An intentional empty object literal.
+ * Is the given object a plain object?
+ *
+ * @param obj - The object to check.
+ * @returns `true` if the given object is a plain object, `false` otherwise.
  */
-export const EMPTY_LITERAL = {}
+export const isPlainObject = (obj: unknown): boolean =>
+  typeof obj === 'object' &&
+  obj !== null &&
+  obj?.constructor === Object &&
+  Object.prototype.toString.call(obj) === '[object Object]'