Use currying

src/config/check.js

@@ -4,6 +4,7 @@ import isPlainObj from 'is-plain-obj'
 import mapObj from 'map-obj'
 
 import { UserError } from '../error/main.js'
+import { curry } from '../utils/functional.js'
 
 // Configuration validation helper functions
 // eslint-disable-next-line max-params
@@ -14,6 +15,8 @@ export const checkArrayItems = function (checkers, value, name, ...args) {
   )
 }
 
+export const cCheckArrayItems = curry(checkArrayItems)
+
 // When array has a single item, it is possible that the value was arrified
 const getIndexName = function (name, index, value) {
   return value.length === 1 ? name : `${name}[${index}]`
@@ -28,6 +31,8 @@ export const checkObjectProps = function (checkers, value, name, ...args) {
   ])
 }
 
+export const cCheckObjectProps = curry(checkObjectProps)
+
 const applyCheckers = function (checkers, value, ...args) {
   return checkers.reduce(
     (valueA, checker) => applyChecker(checker, valueA, ...args),

src/config/normalize.js

@@ -12,9 +12,9 @@ import {
   checkInteger,
   checkString,
   normalizeOptionalArray,
-  checkArrayItems,
+  cCheckArrayItems,
   checkArrayLength,
-  checkObjectProps,
+  cCheckObjectProps,
   checkDefinedString,
   checkJson,
 } from './check.js'
@@ -80,37 +80,31 @@ const NORMALIZERS = {
   cwd: [checkDefinedString, normalizeConfigPath],
   delta: [normalizeDelta],
   force: [checkBoolean],
-  inputs: [checkObjectProps.bind(undefined, [checkJson])],
+  inputs: [cCheckObjectProps([checkJson])],
   limit: [checkInteger, normalizeLimit],
   merge: [checkDefinedString, validateMerge],
   output: [checkDefinedString, condition(normalizeConfigPath, isOutputPath)],
   outliers: [checkBoolean],
   precision: [checkInteger, normalizePrecision],
   quiet: [checkBoolean],
-  reporter: [
-    normalizeOptionalArray,
-    checkArrayItems.bind(undefined, [checkDefinedString]),
-  ],
+  reporter: [normalizeOptionalArray, cCheckArrayItems([checkDefinedString])],
   runner: [
     normalizeOptionalArray,
     checkArrayLength,
-    checkArrayItems.bind(undefined, [checkDefinedString]),
+    cCheckArrayItems([checkDefinedString]),
   ],
   save: [checkBoolean],
-  select: [
-    normalizeOptionalArray,
-    checkArrayItems.bind(undefined, [checkString]),
-  ],
+  select: [normalizeOptionalArray, cCheckArrayItems([checkString])],
   showDiff: [checkBoolean],
   showMetadata: [checkBoolean],
   showPrecision: [checkBoolean],
   showSystem: [checkBoolean],
   showTitles: [checkBoolean],
   since: [normalizeDelta],
-  system: [checkObjectProps.bind(undefined, [checkDefinedString])],
+  system: [cCheckObjectProps([checkDefinedString])],
   tasks: [
     normalizeOptionalArray,
-    checkArrayItems.bind(undefined, [checkDefinedString, normalizeConfigGlob]),
+    cCheckArrayItems([checkDefinedString, normalizeConfigGlob]),
   ],
-  titles: [checkObjectProps.bind(undefined, [checkDefinedString])],
+  titles: [cCheckObjectProps([checkDefinedString])],
 }

src/utils/functional.js

@@ -7,3 +7,13 @@ export const condition = function (callFunc, conditionFunc) {
 const conditionCall = function (callFunc, conditionFunc, ...args) {
   return conditionFunc(...args) ? callFunc(...args) : args[0]
 }
+
+// Allow to use `callFunc(...)` instead of `callFunc.bind(undefined, ...)` when
+// a function is always meant to be bound.
+export const curry = function (callFunc) {
+  return bindArgs.bind(undefined, callFunc)
+}
+
+const bindArgs = function (callFunc, ...boundArgs) {
+  return callFunc.bind(undefined, ...boundArgs)
+}