feat: Add init command

src/commands/init.ts

@@ -0,0 +1,170 @@
+/* eslint-disable unicorn/no-await-expression-member */
+import {Errors, Flags} from '@oclif/core'
+import chalk from 'chalk'
+import {accessSync} from 'node:fs'
+import {constants, readdir, writeFile} from 'node:fs/promises'
+import {join, resolve, sep} from 'node:path'
+
+import {FlaggablePrompt, GeneratorCommand, exec, makeFlags, readPJSON} from '../generator'
+import {validateBin} from '../util'
+
+const validModuleTypes = ['ESM', 'CommonJS']
+const validPackageManagers = ['npm', 'yarn', 'pnpm']
+
+const FLAGGABLE_PROMPTS = {
+  bin: {
+    message: 'Command bin name the CLI will export',
+    validate: (d: string) => validateBin(d) || 'Invalid bin name',
+  },
+  'output-dir': {
+    message: 'Directory to build the CLI in',
+    validate(d: string) {
+      try {
+        accessSync(resolve(d), constants.X_OK)
+        return true
+      } catch {
+        return false
+      }
+    },
+  },
+  'package-manager': {
+    message: 'Select a package manager',
+    options: validPackageManagers,
+    validate: (d: string) => validPackageManagers.includes(d) || 'Invalid package manager',
+  },
+} satisfies Record<string, FlaggablePrompt>
+
+export default class Generate extends GeneratorCommand<typeof Generate> {
+  static description =
+    'This will add the necessary oclif bin files, add oclif config to package.json, and install @oclif/core if needed.'
+
+  static examples = [
+    {
+      command: '<%= config.bin %> <%= command.id %>',
+      description: 'Initialize a new CLI in the current directory with auto-detected module type and package manager',
+    },
+    {
+      command: '<%= config.bin %> <%= command.id %> --output-dir "/path/to/existing/project"',
+      description: 'Initialize a new CLI in a different directory',
+    },
+    {
+      command: '<%= config.bin %> <%= command.id %> --module-type "ESM" --package-manager "npm"',
+      description: 'Supply answers for specific prompts',
+    },
+  ]
+
+  static flaggablePrompts = FLAGGABLE_PROMPTS
+
+  static flags = {
+    ...makeFlags(FLAGGABLE_PROMPTS),
+    'module-type': Flags.option({
+      options: validModuleTypes,
+    })({}),
+  }
+
+  static summary = 'Initialize a new oclif CLI'
+
+  async run(): Promise<void> {
+    const outputDir = await this.getFlagOrPrompt({defaultValue: './', name: 'output-dir', type: 'input'})
+    const location = resolve(outputDir)
+
+    this.log(`Initializing oclif in ${chalk.green(location)}`)
+
+    const packageJSON = (await readPJSON(location))!
+    if (!packageJSON) {
+      throw new Errors.CLIError(`Could not find a package.json file in ${location}`)
+    }
+
+    const bin = await this.getFlagOrPrompt({
+      defaultValue: location.split(sep).at(-1) || '',
+      name: 'bin',
+      type: 'input',
+    })
+
+    let moduleType = this.flags['module-type']
+    if (!moduleType || !validModuleTypes.includes(moduleType)) {
+      if (packageJSON.type === 'module') {
+        moduleType = 'ESM'
+      } else if (packageJSON.type === 'commonjs') {
+        moduleType = 'CommonJS'
+      } else {
+        moduleType = await (
+          await import('@inquirer/select')
+        ).default({
+          choices: validModuleTypes.map((type) => ({name: type, value: type})),
+          message: 'Select a module type',
+        })
+      }
+    }
+
+    this.log(`Using module type ${chalk.green(moduleType)}`)
+
+    const templateOptions = {moduleType}
+    const projectBinPath = join(location, 'bin')
+    await this.template(
+      join(this.templatesDir, 'src', 'init', 'dev.cmd.ejs'),
+      join(projectBinPath, 'dev.cmd'),
+      templateOptions,
+    )
+    await this.template(
+      join(this.templatesDir, 'src', 'init', 'dev.js.ejs'),
+      join(projectBinPath, 'dev.js'),
+      templateOptions,
+    )
+    await this.template(
+      join(this.templatesDir, 'src', 'init', 'run.cmd.ejs'),
+      join(projectBinPath, 'run.cmd'),
+      templateOptions,
+    )
+    await this.template(
+      join(this.templatesDir, 'src', 'init', 'run.js.ejs'),
+      join(projectBinPath, 'run.js'),
+      templateOptions,
+    )
+
+    const updatedPackageJSON = {
+      ...packageJSON,
+      bin: {
+        ...packageJSON.bin,
+        [bin]: './bin/run.js',
+      },
+      oclif: {
+        bin,
+        commands: './dist/commands',
+        dirname: bin,
+        ...packageJSON.oclif,
+      },
+    }
+
+    await writeFile(join(location, 'package.json'), JSON.stringify(updatedPackageJSON, null, 2))
+
+    const installedDeps = Object.keys(packageJSON.dependencies || {})
+    if (!installedDeps.includes('@oclif/core')) {
+      let packageManager = this.flags['package-manager']
+      if (!packageManager || !validPackageManagers.includes(packageManager)) {
+        const rootFiles = await readdir(location)
+        if (rootFiles.includes('package-lock.json')) {
+          packageManager = 'npm'
+        } else if (rootFiles.includes('yarn.lock')) {
+          packageManager = 'yarn'
+        } else if (rootFiles.includes('pnpm-lock.yaml')) {
+          packageManager = 'pnpm'
+        } else {
+          packageManager = await (
+            await import('@inquirer/select')
+          ).default({
+            choices: validPackageManagers.map((manager) => ({name: manager, value: manager})),
+            message: 'Select a package manager',
+          })
+        }
+      }
+
+      await exec(`${packageManager} ${packageManager === 'npm' ? 'install' : 'add'} @oclif/core`, {
+        cwd: location,
+        silent: false,
+      })
+    }
+
+    this.log(`\nCreated CLI ${chalk.green(bin)}`)
+  }
+}

templates/src/init/dev.cmd.ejs

@@ -0,0 +1,12 @@
+<% switch (moduleType) {
+  case 'ESM' : _%>
+@echo off
+
+node --loader ts-node/esm --no-warnings=ExperimentalWarning "%~dp0\dev" %*
+          <%_ break;
+  case 'CommonJS' : _%>
+@echo off
+
+node "%~dp0\dev" %*
+          <%_ break;
+  } _%>

templates/src/init/dev.js.ejs

@@ -0,0 +1,17 @@
+<% switch (moduleType) {
+  case 'ESM' : _%>
+#!/usr/bin/env -S node --loader ts-node/esm --no-warnings=ExperimentalWarning
+
+import {execute} from '@oclif/core'
+await execute({development: true, dir: import.meta.url})
+          <%_ break;
+  case 'CommonJS' : _%>
+#!/usr/bin/env node_modules/.bin/ts-node
+
+// eslint-disable-next-line node/shebang, unicorn/prefer-top-level-await
+(async () => {
+  const oclif = await import('@oclif/core')
+  await oclif.execute({development: true, dir: __dirname})
+})()
+          <%_ break;
+  } _%>

templates/src/init/run.cmd.ejs

@@ -0,0 +1,3 @@
+@echo off
+
+node "%~dp0\run" %*

templates/src/init/run.js.ejs

@@ -0,0 +1,17 @@
+<% switch (moduleType) {
+  case 'ESM' : _%>
+#!/usr/bin/env node
+
+import {execute} from '@oclif/core'
+await execute({dir: import.meta.url})
+          <%_ break;
+  case 'CommonJS' : _%>
+#!/usr/bin/env node
+
+// eslint-disable-next-line unicorn/prefer-top-level-await
+(async () => {
+  const oclif = await import('@oclif/core')
+  await oclif.execute({development: false, dir: __dirname})
+})()
+          <%_ break;
+  } _%>