feat: support package manager-specific create commands

src/index.ts

@@ -19,6 +19,10 @@ import deepmerge from 'deepmerge';
 import minimist from 'minimist';
 import { color, logger } from 'rslog';
 import { x, xSync } from 'tinyexec';
+import {
+  getAgentCreateCommand,
+  replaceCreateCommand,
+} from './package-manager.js';
 import { isNpmTemplate, resolveCustomTemplate } from './template-manager.js';
 
 const __filename = fileURLToPath(import.meta.url);
@@ -82,12 +86,6 @@ function pkgFromUserAgent(userAgent: string | undefined) {
   };
 }
 
-function getAgentCreateCommand(name: string, packageManager: string) {
-  return packageManager === 'nub'
-    ? `nub create ${name}@latest`
-    : `npx -y create-${name}`;
-}
-
 const PACKAGE_MANAGER_FILES = [
   { file: 'pnpm-workspace.yaml', packageManager: 'pnpm' },
 ];
@@ -504,27 +502,7 @@ async function runCommand(
   cwd: string,
   packageManager: string,
 ) {
-  // Replace `npm create` with the equivalent command for the detected package manager
-  if (command.startsWith('npm create ')) {
-    const createReplacements: Record<string, string> = {
-      bun: 'bun create ',
-      nub: 'nub create ',
-      pnpm: 'pnpm create ',
-      yarn: 'yarn create ',
-      deno: 'deno run -A npm:create-',
-    };
-    const replacement = createReplacements[packageManager];
-    if (replacement) {
-      command = command
-        .replace('npm create ', replacement)
-        // other package managers don't need the extra `--`
-        .replace(' -- --', ' --');
-    }
-    // Yarn v1 does not support `@latest` tag
-    if (packageManager === 'yarn') {
-      command = command.replace('@latest', '');
-    }
-  }
+  command = replaceCreateCommand(command, packageManager);
 
   const result = await x(command, [], {
     nodeOptions: {

src/package-manager.ts

@@ -0,0 +1,59 @@
+const CREATE_COMMAND_REPLACEMENTS: Record<string, string> = {
+  bun: 'bun create ',
+  nub: 'nub create ',
+  pnpm: 'pnpm create ',
+  yarn: 'yarn create ',
+  deno: 'deno run -A npm:create-',
+};
+
+function addNpmYesFlag(command: string) {
+  const separatorIndex = command.indexOf(' -- ');
+  const npmCommand =
+    separatorIndex === -1 ? command : command.slice(0, separatorIndex);
+
+  if (/(?:^|\s)(?:-y|--yes(?:=\S+)?)(?=\s|$)/.test(npmCommand)) {
+    return command;
+  }
+
+  return separatorIndex === -1
+    ? `${command} -y`
+    : `${npmCommand} -y${command.slice(separatorIndex)}`;
+}
+
+export function replaceCreateCommand(command: string, packageManager: string) {
+  if (!command.startsWith('npm create ')) {
+    return command;
+  }
+
+  if (packageManager === 'npm') {
+    return addNpmYesFlag(command);
+  }
+
+  const replacement = CREATE_COMMAND_REPLACEMENTS[packageManager];
+  if (!replacement) {
+    return command;
+  }
+
+  const replacedCommand = command
+    .replace('npm create ', replacement)
+    // Other package managers don't need the extra `--`.
+    .replace(' -- --', ' --');
+
+  // Yarn v1 does not support the `@latest` tag.
+  return packageManager === 'yarn'
+    ? replacedCommand.replace('@latest', '')
+    : replacedCommand;
+}
+
+export function getAgentCreateCommand(name: string, packageManager: string) {
+  if (packageManager === 'npm') {
+    return `npx -y create-${name}@latest`;
+  }
+
+  const npmCreateCommand = `npm create ${name}@latest`;
+  const createCommand = replaceCreateCommand(npmCreateCommand, packageManager);
+
+  return createCommand === npmCreateCommand
+    ? `npx -y create-${name}@latest`
+    : createCommand;
+}

test/package-manager.test.ts

@@ -0,0 +1,46 @@
+import { expect, test } from 'rstack/test';
+import {
+  getAgentCreateCommand,
+  replaceCreateCommand,
+} from '../src/package-manager';
+
+test.each([
+  ['npm', 'npx -y create-test@latest'],
+  ['pnpm', 'pnpm create test@latest'],
+  ['yarn', 'yarn create test'],
+  ['bun', 'bun create test@latest'],
+  ['deno', 'deno run -A npm:create-test@latest'],
+  ['unknown', 'npx -y create-test@latest'],
+])('should get the agent create command for %s', (packageManager, expected) => {
+  expect(getAgentCreateCommand('test', packageManager)).toBe(expected);
+});
+
+test.each([
+  ['npm', 'npm create test@latest -y -- --template vanilla'],
+  ['pnpm', 'pnpm create test@latest --template vanilla'],
+  ['yarn', 'yarn create test --template vanilla'],
+  ['bun', 'bun create test@latest --template vanilla'],
+  ['deno', 'deno run -A npm:create-test@latest --template vanilla'],
+  ['unknown', 'npm create test@latest -- --template vanilla'],
+])('should replace the create command for %s', (packageManager, expected) => {
+  expect(
+    replaceCreateCommand(
+      'npm create test@latest -- --template vanilla',
+      packageManager,
+    ),
+  ).toBe(expected);
+});
+
+test.each([
+  'npm create test@latest -y -- --template vanilla',
+  'npm create test@latest --yes -- --template vanilla',
+  'npm create test@latest --yes=false -- --template vanilla',
+])('should preserve an existing npm yes flag in %s', (command) => {
+  expect(replaceCreateCommand(command, 'npm')).toBe(command);
+});
+
+test('should distinguish an npm flag from a scaffolder argument', () => {
+  expect(replaceCreateCommand('npm create test@latest -- --yes', 'npm')).toBe(
+    'npm create test@latest -y -- --yes',
+  );
+});