Revert "Revert "Migrate task arguments helper to CommonJS""

This reverts commit d44da27.

packages/govuk-frontend/postcss.config.mjs

@@ -2,7 +2,7 @@ import autoprefixer from 'autoprefixer'
 import cssnano from 'cssnano'
 import cssnanoPresetDefault from 'cssnano-preset-default'
 import { pkg } from 'govuk-frontend-config'
-import { isDev } from 'govuk-frontend-tasks/helpers/task-arguments.mjs'
+import { isDev } from 'govuk-frontend-tasks/helpers/task-arguments.js'
 import postcss from 'postcss'
 import scss from 'postcss-scss'
 

shared/tasks/helpers/task-arguments.mjs → shared/tasks/helpers/task-arguments.js

@@ -1,7 +1,7 @@
-import parser from 'yargs-parser'
+const parser = require('yargs-parser')
 
 // Non-flag arguments as tasks
 const { _: tasks } = parser(process.argv)
 
 // Check for development task
-export const isDev = tasks.includes('dev')
+module.exports.isDev = tasks.includes('dev')

shared/tasks/helpers/task-arguments.unit.test.mjs → shared/tasks/helpers/task-arguments.unit.test.js

@@ -26,35 +26,35 @@ describe('Task arguments', () => {
       it('is flagged false', async () => {
         process.argv = [...argv]
 
-        const { isDev } = await import('./task-arguments.mjs')
+        const { isDev } = require('./task-arguments.js')
         expect(isDev).toBe(false)
       })
 
       it("is flagged false for 'gulp build:app'", async () => {
         process.argv = [...argv, 'build:app']
 
-        const { isDev } = await import('./task-arguments.mjs')
+        const { isDev } = require('./task-arguments.js')
         expect(isDev).toBe(false)
       })
 
       it("is flagged false for 'gulp build:package'", async () => {
         process.argv = [...argv, 'build:package']
 
-        const { isDev } = await import('./task-arguments.mjs')
+        const { isDev } = require('./task-arguments.js')
         expect(isDev).toBe(false)
       })
 
       it("is flagged false for 'gulp build:release'", async () => {
         process.argv = [...argv, 'build:release']
 
-        const { isDev } = await import('./task-arguments.mjs')
+        const { isDev } = require('./task-arguments.js')
         expect(isDev).toBe(false)
       })
 
       it("is flagged true for 'gulp dev'", async () => {
         process.argv = [...argv, 'dev']
 
-        const { isDev } = await import('./task-arguments.mjs')
+        const { isDev } = require('./task-arguments.js')
         expect(isDev).toBe(true)
       })
     })

shared/tasks/npm.mjs

@@ -2,7 +2,7 @@ import runScript from '@npmcli/run-script'
 import { paths } from 'govuk-frontend-config'
 import PluginError from 'plugin-error'
 
-import { isDev } from './helpers/task-arguments.mjs'
+import { isDev } from './helpers/task-arguments.js'
 import { task } from './index.mjs'
 
 /**