feat: add support for Array types (#42)

* feat: add surpport for Array types

* fix: add conditional statements

* fix: make dot nested options behave the same

* docs: add the description of config.type

Author: Eliaz

README.md

@@ -310,6 +310,7 @@ Add a global option.
 The option also accepts a third argument `config` for addtional option config:
 
 - `config.default`: Default value for the option.
+- `config.type`: `any[]` When set to `[]`, the option value returns an array type. You can also use a conversion function such as `[String]`, which will invoke the option value with `String`.
 
 #### cli.parse(argv?)
 

src/CAC.ts

@@ -8,7 +8,7 @@ import Command, {
   CommandExample
 } from './Command'
 import { OptionConfig } from './Option'
-import { getMriOptions, camelcase, setDotProp } from './utils'
+import { getMriOptions, camelcase, setDotProp, setByType } from './utils'
 
 interface ParsedArgv {
   args: ReadonlyArray<string>
@@ -263,12 +263,23 @@ class CAC extends EventEmitter {
         ? command.config.ignoreOptionDefaultValue
         : this.globalCommand.config.ignoreOptionDefaultValue
 
-    if (!ignoreDefault) {
-      for (const cliOption of cliOptions) {
-        if (cliOption.config.default !== undefined) {
-          for (const name of cliOption.names) {
-            options[name] = cliOption.config.default
-          }
+    let transforms = Object.create(null)
+
+    for (const cliOption of cliOptions) {
+      if (!ignoreDefault && cliOption.config.default !== undefined) {
+        for (const name of cliOption.names) {
+          options[name] = cliOption.config.default
+        }
+      }
+
+      // If options type is defined
+      if (Array.isArray(cliOption.config.type)) {
+        if (transforms[cliOption.name] === undefined) {
+          transforms[cliOption.name] = Object.create(null)
+
+          transforms[cliOption.name]['shouldTransform'] = true
+          transforms[cliOption.name]['transformFunction'] =
+            cliOption.config.type[0]
         }
       }
     }
@@ -279,6 +290,7 @@ class CAC extends EventEmitter {
         return i === 0 ? camelcase(v) : v
       })
       setDotProp(options, keys, parsed[key])
+      setByType(options, transforms)
     }
 
     return {

src/Option.ts

@@ -2,6 +2,7 @@ import { removeBrackets } from './utils'
 
 interface OptionConfig {
   default?: any
+  type?: any[]
 }
 
 export default class Option {

src/__test__/index.test.ts

@@ -91,3 +91,50 @@ test('negated optional validation', () => {
   cli.globalCommand.checkOptionValue()
   expect(options.config).toBe(false)
 })
+
+test('array types without transformFunction', () => {
+  const cli = cac()
+
+  cli
+    .option(
+      '--externals <external>',
+      'Add externals(can be used for multiple times',
+      {
+        type: []
+      }
+    )
+    .option('--scale [level]', 'Scaling level')
+
+  const { options: options1 } = cli.parse(
+    `node bin --externals.env.prod production --scale`.split(' ')
+  )
+  expect(options1.externals).toEqual([{ env: { prod: 'production' } }])
+  expect(options1.scale).toEqual(true)
+
+  const { options: options2 } = cli.parse(
+    `node bin --externals foo --externals bar`.split(' ')
+  )
+  expect(options2.externals).toEqual(['foo', 'bar'])
+
+  const { options: options3 } = cli.parse(
+    `node bin --externals.env foo --externals.env bar`.split(' ')
+  )
+  expect(options3.externals).toEqual([{ env: ['foo', 'bar'] }])
+})
+
+test('array types with transformFunction', () => {
+  const cli = cac()
+
+  cli
+    .command('build [entry]', 'Build your app')
+    .option('--config <configFlie>', 'Use config file for building', {
+      type: [String]
+    })
+    .option('--scale [level]', 'Scaling level')
+
+  const { options } = cli.parse(
+    `node bin build app.js --config config.js --scale`.split(' ')
+  )
+  expect(options.config).toEqual(['config.js'])
+  expect(options.scale).toEqual(true)
+})

src/utils.ts

@@ -115,3 +115,20 @@ export const setDotProp = (
         : []
   }
 }
+
+export const setByType = (
+  obj: { [k: string]: any },
+  transforms: { [k: string]: any }
+) => {
+  for (const key of Object.keys(transforms)) {
+    const transform = transforms[key]
+
+    if (transform.shouldTransform) {
+      obj[key] = Array.prototype.concat.call([], obj[key])
+
+      if (typeof transform.transformFunction === 'function') {
+        obj[key] = obj[key].map(transform.transformFunction)
+      }
+    }
+  }
+}