feat(cli): add help command #8391

packages/taro-cli/src/presets/commands/help.ts

@@ -0,0 +1,51 @@
+import { IPluginContext } from '@tarojs/service'
+
+function supplementBlank (length) {
+  return Array(length).map(() => '').join(' ')
+}
+
+export function printHelpLog (command, optionsList: Map<string, string>, synopsisList?: Set<string>) {
+  console.log(`Usage: taro ${command} [options]`)
+  console.log()
+  console.log('Options:')
+  const keys = Array.from(optionsList.keys())
+  const maxLength = keys.reduce((v1, v2) => {
+    return v1.length > v2.length ? v1 : v2
+  }).length + 3
+  optionsList.forEach((v, k) => {
+    const supplementBlankLength = maxLength - k.length
+    console.log(`  ${k}${supplementBlank(supplementBlankLength)}${v}`)
+  })
+  if (synopsisList && synopsisList.size) {
+    console.log()
+    console.log('Synopsis:')
+    synopsisList.forEach(item => {
+      console.log(`  $ ${item}`)
+    })
+  }
+}
+
+export default (ctx: IPluginContext) => {
+  ctx.registerCommand({
+    name: 'help',
+    synopsisList: [
+      'taro -h',
+      'taro --help'
+    ],
+    async fn ({ _, options }) {
+      const command = ctx.ctx.commands.get(_[1])
+      if (!command) {
+        console.log(`命令 taro help ${_[1]} 中 ${_[1]} 不存在，试试 taro -h 再看看呢？`)
+        return
+      }
+      const defaultOptionsMap = new Map()
+      defaultOptionsMap.set('-h, --help', 'output usage information')
+      let customOptionsMap = new Map(Object.entries(options))
+      if (command?.optionsMap) {
+        customOptionsMap = new Map(Object.entries(command?.optionsMap))
+      }
+      const optionsMap = new Map([...customOptionsMap, ...defaultOptionsMap])
+      printHelpLog(command.name, optionsMap, command?.synopsisList ? new Set(command?.synopsisList) : new Set())
+    }
+  })
+}

packages/taro-cli/src/presets/index.ts

@@ -18,6 +18,7 @@ export default () => {
       path.resolve(__dirname, 'commands', 'convert.js'),
       path.resolve(__dirname, 'commands', 'update.js'),
       path.resolve(__dirname, 'commands', 'inspect.js'),
+      path.resolve(__dirname, 'commands', 'help.js'),
 
       // files
       path.resolve(__dirname, 'files', 'writeFileToDist.js'),