fix: run wb through package manager in playwright web server

packages/wbfy/src/fixers/playwrightConfig.ts

@@ -6,6 +6,7 @@ import ts from 'typescript';
 import { logger } from '../logger.js';
 import type { PackageConfig } from '../packageConfig.js';
 import { fsUtil } from '../utils/fsUtil.js';
+import { getPackageManagerCommand } from '../utils/packageCapabilities.js';
 import { promisePool } from '../utils/promisePool.js';
 
 type ParsedValue =
@@ -30,32 +31,33 @@ const asObject = (properties: Record<string, ParsedValue>, extraMembers: string[
   value: toParsedObject(properties, extraMembers),
 });
 
-const defaultConfig = toParsedObject({
-  forbidOnly: literal('!!process.env.CI'),
-  retries: literal('process.env.PWDEBUG ? 0 : process.env.CI ? 5 : 1'),
-  use: asObject({
-    baseURL: literal('process.env.NEXT_PUBLIC_BASE_URL'),
-    trace: literal("process.env.CI ? 'on-first-retry' : 'retain-on-failure'"),
-    screenshot: literal("process.env.CI ? 'only-on-failure' : 'on'"),
-    video: literal("process.env.CI ? 'on-first-retry' : 'retain-on-failure'"),
-  }),
-  webServer: asObject({
-    command: literal("'wb start --mode test'"),
-    url: literal('process.env.NEXT_PUBLIC_BASE_URL'),
-    reuseExistingServer: literal('!!process.env.CI'),
-    timeout: literal('300_000'),
-    stdout: literal("'pipe'"),
-    stderr: literal("'pipe'"),
-    env: literal(`{
+const createDefaultConfig = (config: PackageConfig): ParsedObject =>
+  toParsedObject({
+    forbidOnly: literal('!!process.env.CI'),
+    retries: literal('process.env.PWDEBUG ? 0 : process.env.CI ? 5 : 1'),
+    use: asObject({
+      baseURL: literal('process.env.NEXT_PUBLIC_BASE_URL'),
+      trace: literal("process.env.CI ? 'on-first-retry' : 'retain-on-failure'"),
+      screenshot: literal("process.env.CI ? 'only-on-failure' : 'on'"),
+      video: literal("process.env.CI ? 'on-first-retry' : 'retain-on-failure'"),
+    }),
+    webServer: asObject({
+      command: literal(getWbStartTestCommand(config)),
+      url: literal('process.env.NEXT_PUBLIC_BASE_URL'),
+      reuseExistingServer: literal('!!process.env.CI'),
+      timeout: literal('300_000'),
+      stdout: literal("'pipe'"),
+      stderr: literal("'pipe'"),
+      env: literal(`{
   ...process.env,
   PRISMA_USER_CONSENT_FOR_DANGEROUS_AI_ACTION: 'true',
 }`),
-    gracefulShutdown: literal(`{
+      gracefulShutdown: literal(`{
   signal: 'SIGTERM',
   timeout: 500,
 }`),
-  }),
-});
+    }),
+  });
 
 function toParsedObject(properties: Record<string, ParsedValue>, extraMembers: string[] = []): ParsedObject {
   return {
@@ -83,8 +85,8 @@ export async function fixPlaywrightConfig(config: PackageConfig): Promise<void>
     if (!parsed) return;
 
     // Keep filling missing defaults, but don't overwrite local adjustments on every regeneration.
-    const merged = mergeParsedObjects(defaultConfig, parsed);
-    setWebServerCommand(merged);
+    const merged = mergeParsedObjects(createDefaultConfig(config), parsed);
+    setWebServerCommand(merged, config);
 
     const newObjectLiteral = stringifyValue({ kind: 'object', value: merged }, 0);
     const start = extractedObjectLiteral.node.getStart(extractedObjectLiteral.source);
@@ -153,13 +155,18 @@ function getEnvFilePaths(dirPath: string): string[] {
   return envFilePaths;
 }
 
-function setWebServerCommand(object: ParsedObject): void {
+function setWebServerCommand(object: ParsedObject, config: PackageConfig): void {
   const webServer = object.properties.webServer;
   if (webServer?.kind !== 'object') return;
 
   // wb owns the canonical test-server startup path; keep custom Playwright
-  // server settings while normalizing the command itself.
-  webServer.value.properties.command = literal("'wb start --mode test'");
+  // server settings while normalizing the command itself. Invoke wb through the
+  // package manager because target repos install wb as a package dependency.
+  webServer.value.properties.command = literal(getWbStartTestCommand(config));
+}
+
+function getWbStartTestCommand(config: PackageConfig): string {
+  return `'${getPackageManagerCommand(config)} wb start --mode test'`;
 }
 
 function extractDefineConfigObjectLiteral(content: string): ExtractedObjectLiteral | undefined {

packages/wbfy/src/generators/agents.ts

@@ -3,6 +3,7 @@ import path from 'node:path';
 import { logger } from '../logger.js';
 import type { PackageConfig } from '../packageConfig.js';
 import { fsUtil } from '../utils/fsUtil.js';
+import { getPackageManagerCommand } from '../utils/packageCapabilities.js';
 import { promisePool } from '../utils/promisePool.js';
 
 export async function generateAgentInstructions(rootConfig: PackageConfig, allConfigs: PackageConfig[]): Promise<void> {
@@ -45,7 +46,7 @@ function generateAgentInstruction(
   toolName: string,
   extraContent?: string
 ): string {
-  const packageManager = rootConfig.isBun ? 'bun' : 'yarn';
+  const packageManager = getPackageManagerCommand(rootConfig);
   const baseContent = `
 ## Project Information
 
@@ -74,7 +75,7 @@ function generateAgentInstruction(
   - If not specified, make sure to add a new line at the end of your commit message${rootConfig.isWillBoosterRepo ? ` with: \`Co-authored-by: WillBooster (${toolName}) <agent@willbooster.com>\`` : ''}.
   - Always create new commits. Avoid using \`--amend\`.
 - Always use heredoc syntax when passing multi-line content to any command.
-${hasPlaywrightTestServer(allConfigs) ? `- Use \`wb start --mode test\` to launch a web server for debugging or testing.` : ''}
+${hasPlaywrightTestServer(allConfigs) ? `- Use \`${packageManager} wb start --mode test\` to launch a web server for debugging or testing.` : ''}
 
 ${generateAgentCodingStyle(allConfigs)}
 `

packages/wbfy/src/utils/packageCapabilities.ts

@@ -12,3 +12,7 @@ export function doesContainJsOrTs(config: PackageConfig): boolean {
 export function doesContainJava(config: PackageConfig): boolean {
   return config.doesContainJava || config.doesContainJavaInPackages;
 }
+
+export function getPackageManagerCommand(config: Pick<PackageConfig, 'isBun'>): 'bun' | 'yarn' {
+  return config.isBun ? 'bun' : 'yarn';
+}

packages/wbfy/test/agentInstructions.test.ts

@@ -35,7 +35,7 @@ test('mentions wb test server startup for Playwright projects on the first run',
   await promisePool.promiseAll();
 
   const content = await fs.promises.readFile(path.join(dirPath, 'AGENTS.md'), 'utf8');
-  expect(content).toContain('Use `wb start --mode test` to launch a web server for debugging or testing.');
+  expect(content).toContain('Use `bun wb start --mode test` to launch a web server for debugging or testing.');
 });
 
 function createTempDir(): string {