fix(cli): preserve invoked cwd for local launcher (#299)

cli/src/utils/invokedCwd.ts

@@ -0,0 +1,9 @@
+import { isAbsolute } from 'node:path';
+
+export function getInvokedCwd(): string {
+    const invokedCwd = process.env.HAPI_INVOKED_CWD?.trim();
+    if (invokedCwd && isAbsolute(invokedCwd)) {
+        return invokedCwd;
+    }
+    return process.cwd();
+}

cli/src/utils/spawnHappyCLI.test.ts

@@ -12,6 +12,7 @@ vi.mock('child_process', async () => {
 });
 
 const originalPlatformDescriptor = Object.getOwnPropertyDescriptor(process, 'platform');
+const originalInvokedCwd = process.env.HAPI_INVOKED_CWD;
 
 function setPlatform(value: string) {
   Object.defineProperty(process, 'platform', {
@@ -39,6 +40,11 @@ describe('spawnHappyCLI windowsHide behavior', () => {
 
   beforeEach(() => {
     vi.clearAllMocks();
+    if (originalInvokedCwd === undefined) {
+      delete process.env.HAPI_INVOKED_CWD;
+    } else {
+      process.env.HAPI_INVOKED_CWD = originalInvokedCwd;
+    }
   });
 
   afterAll(() => {
@@ -88,4 +94,49 @@ describe('spawnHappyCLI windowsHide behavior', () => {
     expect(options.detached).toBe(true);
     expect('windowsHide' in options).toBe(false);
   });
+
+  it('forces Bun child processes to run with the cli project root as cwd', async () => {
+    const { getHappyCliCommand } = await import('./spawnHappyCLI');
+
+    const command = getHappyCliCommand(['mcp', '--url', 'http://127.0.0.1:1234/']);
+    const isBunRuntime = Boolean((process.versions as Record<string, string | undefined>).bun);
+
+    expect(command.command).toBe(process.execPath);
+    if (isBunRuntime) {
+      expect(command.args[0]).toBe('--cwd');
+      expect(command.args[1].replace(/\\/g, '/')).toMatch(/\/hapi\/cli$/);
+      expect(command.args[2].replace(/\\/g, '/')).toMatch(/\/hapi\/cli\/src\/index\.ts$/);
+    } else {
+      expect(command.args.some((arg) => arg.replace(/\\/g, '/').endsWith('/hapi/cli/src/index.ts'))).toBe(true);
+    }
+  });
+
+  it('passes invoked workspace cwd to child processes when cwd is provided', async () => {
+    const { spawnHappyCLI } = await import('./spawnHappyCLI');
+    const childCwd = 'C:\\workspace\\project';
+
+    spawnHappyCLI(['runner', 'start-sync'], {
+      cwd: childCwd,
+      stdio: 'ignore'
+    });
+
+    const options = getSpawnOptionsOrThrow();
+    expect(options.env?.HAPI_INVOKED_CWD).toBe(childCwd);
+  });
+
+  it('keeps an existing absolute HAPI_INVOKED_CWD when provided explicitly', async () => {
+    const { spawnHappyCLI } = await import('./spawnHappyCLI');
+    const inheritedInvokedCwd = 'C:\\workspace\\other-project';
+
+    spawnHappyCLI(['runner', 'start-sync'], {
+      cwd: 'C:\\workspace\\project',
+      env: {
+        HAPI_INVOKED_CWD: inheritedInvokedCwd
+      },
+      stdio: 'ignore'
+    });
+
+    const options = getSpawnOptionsOrThrow();
+    expect(options.env?.HAPI_INVOKED_CWD).toBe(inheritedInvokedCwd);
+  });
 });

cli/src/utils/spawnHappyCLI.ts

@@ -26,7 +26,8 @@
  */
 
 import { spawn, SpawnOptions, type ChildProcess } from 'child_process';
-import { join } from 'node:path';
+import { join, isAbsolute, resolve, win32 } from 'node:path';
+import { fileURLToPath } from 'node:url';
 import { isBunCompiled, projectPath } from '@/projectPath';
 import { logger } from '@/ui/logger';
 import { existsSync } from 'node:fs';
@@ -48,6 +49,28 @@ export interface HappyCliCommand {
   args: string[];
 }
 
+function isCrossPlatformAbsolutePath(value: string): boolean {
+  return isAbsolute(value) || win32.isAbsolute(value);
+}
+
+function resolveInvokedCwd(cwd: SpawnOptions['cwd']): string {
+  if (cwd instanceof URL) {
+    return fileURLToPath(cwd);
+  }
+
+  if (typeof cwd === 'string' && cwd.trim().length > 0) {
+    const normalizedCwd = cwd.trim();
+    return isCrossPlatformAbsolutePath(normalizedCwd) ? normalizedCwd : resolve(normalizedCwd);
+  }
+
+  const inheritedInvokedCwd = process.env.HAPI_INVOKED_CWD?.trim();
+  if (inheritedInvokedCwd && isCrossPlatformAbsolutePath(inheritedInvokedCwd)) {
+    return inheritedInvokedCwd;
+  }
+
+  return process.cwd();
+}
+
 export function getHappyCliCommand(args: string[]): HappyCliCommand {
   // Compiled binary mode: just use the executable directly
   if (isBunCompiled()) {
@@ -63,10 +86,12 @@ export function getHappyCliCommand(args: string[]): HappyCliCommand {
   const isBunRuntime = Boolean((process.versions as Record<string, string | undefined>).bun);
 
   if (isBunRuntime) {
-    // Bun can run TypeScript directly
+    // Bun can run TypeScript directly.
+    // Force Bun's cwd to the CLI project root so alias resolution via bunfig.toml
+    // keeps working even when external tools launch HAPI from another workspace.
     return {
       command: process.execPath,
-      args: [entrypoint, ...args]
+      args: ['--cwd', projectRoot, entrypoint, ...args]
     };
   }
 
@@ -108,6 +133,14 @@ export function spawnHappyCLI(args: string[], options: SpawnOptions = {}): Child
   // On Windows, detached processes allocate a new console window by default.
   // windowsHide: true suppresses this to prevent cmd windows from accumulating.
   const finalOptions: SpawnOptions = { ...options };
+  if (!isBunCompiled()) {
+    const finalEnv = { ...process.env, ...options.env };
+    const invokedCwd = finalEnv.HAPI_INVOKED_CWD?.trim();
+    finalEnv.HAPI_INVOKED_CWD = invokedCwd && isCrossPlatformAbsolutePath(invokedCwd)
+      ? invokedCwd
+      : resolveInvokedCwd(options.cwd);
+    finalOptions.env = finalEnv;
+  }
   if (process.platform === 'win32' && options.detached) {
     finalOptions.windowsHide = true;
   }

cli/src/utils/worktreeEnv.ts

@@ -4,6 +4,7 @@ import { basename, dirname, isAbsolute, resolve } from 'node:path';
 
 import type { WorktreeInfo } from '@/runner/worktree';
 import { logger } from '@/ui/logger';
+import { getInvokedCwd } from '@/utils/invokedCwd';
 
 export function readWorktreeEnv(): WorktreeInfo | null {
     return readWorktreeFromEnv() ?? readWorktreeFromGit();
@@ -39,7 +40,7 @@ function readWorktreeFromGit(): WorktreeInfo | null {
     let result: WorktreeInfo | null = null;
 
     try {
-        const cwd = process.cwd();
+        const cwd = getInvokedCwd();
         const isInside = runGit(['rev-parse', '--is-inside-work-tree'], cwd);
         if (isInside !== 'true') {
             return null;