Improve normalization

src/config/check.js

@@ -19,6 +19,12 @@ export const checkBoolean = function (value, name) {
   }
 }
 
+export const checkInteger = function (value, name) {
+  if (!Number.isInteger(value)) {
+    throw new UserError(`'${name}' must be an integer: ${inspect(value)}`)
+  }
+}
+
 // Many array configuration properties can optionally a single element, for
 // simplicity providing it is the most common use case.
 // We also allow duplicate values but remove them.

src/config/normalize.js

@@ -6,6 +6,7 @@ import { normalizePrecision } from '../run/precision.js'
 
 import {
   checkBoolean,
+  checkInteger,
   checkStringsObject,
   normalizeOptionalArray,
   checkArrayLength,
@@ -52,36 +53,15 @@ const normalizePropValue = function (value, propName, name) {
     return value
   }
 
-  const newValue = normalizers.reduce(
-    (valueA, normalizer) => normalizer(valueA, name),
+  return normalizers.reduce(
+    (valueA, normalizer) => applyNormalizer(valueA, name, normalizer),
     value,
   )
-  return newValue === undefined ? value : newValue
-}
-
-const normalizeReporter = function (value, name) {
-  const valueA = normalizeOptionalArray(value)
-  checkDefinedStringArray(valueA, name)
-  return valueA
-}
-
-const normalizeRunner = function (value, name) {
-  const valueA = normalizeOptionalArray(value)
-  checkDefinedStringArray(valueA, name)
-  checkArrayLength(valueA, name)
-  return valueA
-}
-
-const normalizeSelect = function (value, name) {
-  const valueA = normalizeOptionalArray(value)
-  checkStringArray(valueA, name)
-  return valueA
 }
 
-const normalizeTasks = function (value, name) {
-  const valueA = normalizeOptionalArray(value)
-  checkDefinedStringArray(valueA, name)
-  return valueA
+const applyNormalizer = function (value, name, normalizer) {
+  const newValue = normalizer(value, name)
+  return newValue === undefined ? value : newValue
 }
 
 const validateTitles = function (value, name) {
@@ -92,17 +72,17 @@ const validateTitles = function (value, name) {
 
 const NORMALIZERS = {
   inputs: [checkJsonObject],
-  limit: [normalizeLimit],
+  limit: [checkInteger, normalizeLimit],
   merge: [validateMerge],
   outliers: [checkBoolean],
-  precision: [normalizePrecision],
-  reporter: [normalizeReporter],
-  runner: [normalizeRunner],
-  select: [normalizeSelect],
+  precision: [checkInteger, normalizePrecision],
+  reporter: [normalizeOptionalArray, checkDefinedStringArray],
+  runner: [normalizeOptionalArray, checkDefinedStringArray, checkArrayLength],
+  select: [normalizeOptionalArray, checkStringArray],
   showDiff: [checkBoolean],
   showPrecision: [checkBoolean],
   showTitles: [checkBoolean],
   system: [checkStringsObject],
-  tasks: [normalizeTasks],
+  tasks: [normalizeOptionalArray, checkDefinedStringArray],
   titles: [validateTitles],
 }

src/history/compare/normalize.js

@@ -1,14 +1,6 @@
-import { UserError } from '../../error/main.js'
-
 // Parse the `limit` configuration property.
 // It is an integer representing a percentage.
-export const normalizeLimit = function (limit, name) {
-  if (!Number.isInteger(limit)) {
-    throw new UserError(
-      `'${name}' must be an integer (representing a percentage): ${limit}`,
-    )
-  }
-
+export const normalizeLimit = function (limit) {
   return limit / PERCENTAGE_RATIO
 }
 

src/history/merge/id.js

@@ -5,10 +5,10 @@ import { v4 as uuidv4, validate as isUuid } from 'uuid'
 import { UserError } from '../../error/main.js'
 
 // Validate `merge` property
-export const validateMerge = function (value, propName) {
+export const validateMerge = function (value, name) {
   if (!isValidId(value) && value !== LAST_ID) {
     throw new UserError(
-      `'${propName}' must be "${LAST_ID}" or a UUID: ${inspect(value)}`,
+      `'${name}' must be "${LAST_ID}" or a UUID: ${inspect(value)}`,
     )
   }
 }

src/run/precision.js

@@ -75,12 +75,6 @@ import { UserError } from '../error/main.js'
 //        - this can happen inside the same run (due to previous runs being
 //          merged to current one)
 export const normalizePrecision = function (precision, propName) {
-  if (!Number.isInteger(precision)) {
-    throw new UserError(
-      `'${propName}' must be a positive integer: ${precision}`,
-    )
-  }
-
   const precisionA = PRECISION_TARGETS[precision]
 
   if (precisionA === undefined) {