[Bug]: Simulator test fails on mixed iOS and watchOS test plans in 2.7.0

Commencez par reproduire l’échec avec Repro.xcodeproj et Repro.xctestplan à l’aide de la commande de test du simulateur, puis comparez les invocations 2.7.0 et 2.6.2 dans xcodebuild-invocations.txt. Suivez la gestion de la destination de test-without-building après la découverte des tests iOS et watchOS. Le travail est terminé lorsque le plan de test mixte s’exécute sur des simulateurs appairés sans casser le cas iOS-only.

Bug Description

simulator test fails on XcodeBuildMCP 2.7.0 when the scheme's test plan contains both iOS and watchOS unit test targets. The same command, project and simulator pass on 2.6.2.

2.7.0 builds the project and discovers both tests, then the prepared test phase fails to resolve the requested iOS Simulator. Removing only the watchOS test target from the test plan makes 2.7.0 pass.

I have attached a standalone repro with three targets and no dependencies, package manager or code signing.

Debug Output

⚙️ XcodeBuildMCP Doctor

   Generated: 2026-08-11T00:51:34.307Z
   Server Version: 2.7.0
   Output Mode: Redacted (default)

System Information
  platform: darwin
  release: 25.6.0
  arch: arm64
  cpus: 15 x Apple M5 Pro
  memory: 48 GB
  hostname: <redacted>
  username: <redacted>
  homedir: /Users/<redacted>
  tmpdir: /var/folders/ql/lrbqh2nx1615gy6k6tptrdjc0000gn/T

Node.js Information
  version: v26.7.0
  execPath: /opt/homebrew/Cellar/node/26.7.0/bin/node
  pid: 93030
  ppid: 89346
  platform: darwin
  arch: arm64
  cwd: /Users/<redacted>/Documents/Work/<redacted>
  argv: /opt/homebrew/Cellar/node/26.7.0/bin/node /opt/homebrew/Cellar/xcodebuildmcp/2.7.0/libexec/build/doctor-cli.js

Process Tree
  Running under Xcode: No
  93030 (ppid 89346): node -- node /opt/homebrew/Cellar/xcodebuildmcp/2.7.0/libexec/build/doctor-cli.js
  89346 (ppid 89339): /opt/homebrew/li -- /opt/homebrew/lib/node_modules/@openai/codex/node_modules/@openai/codex-darwin-arm64/vendor/aarch64-apple-darwin/bin/codex --yolo
  89339 (ppid 88662): node -- node /opt/homebrew/bin/codex --yolo
  88662 (ppid 9938): -zsh -- -zsh
  9938 (ppid 1): /opt/homebrew/bi -- /opt/homebrew/bin/herdr server
  1 (ppid 0): /sbin/launchd -- /sbin/launchd

Xcode Information
  version: Xcode 26.6 - Build version 17F113
  path: /Applications/Xcode-26.6.0.app/Contents/Developer
  selectedXcode: /Applications/Xcode-26.6.0.app/Contents/Developer/usr/bin/xcodebuild
  xcrunVersion: xcrun version 72.

Dependencies
  axe: 1.8.0
  mise: 2026.8.3 macos-arm64 (2026-08-07)

Environment Variables
  INCREMENTAL_BUILDS_ENABLED: (not set)
  DEVELOPER_DIR: (not set)
  HOME: /Users/<redacted>
  USER: <redacted>
  TMPDIR: /var/folders/ql/lrbqh2nx1615gy6k6tptrdjc0000gn/T/
  NODE_ENV: (not set)
  SENTRY_DISABLED: (not set)
  AXE_PATH: (not set)
  XBMCP_LAUNCH_JSON_WAIT_MS: (not set)
  XCODEBUILDMCP_DEBUGGER_BACKEND: (not set)
  XCODEBUILDMCP_UI_DEBUGGER_GUARD_MODE: (not set)
  XCODEBUILDMCP_RUNTIME: cli
  XCODEBUILDMCP_SILENCE_LOGS: true

PATH
  /opt/homebrew/lib/node_modules/@openai/codex/node_modules/@openai/codex-darwin-arm64/vendor/aarch64-apple-darwin/codex-path
  /opt/homebrew/opt/openjdk@17/bin
  /Users/<redacted>/.rbenv/shims
  /Users/<redacted>/.local/bin
  /opt/homebrew/bin
  /opt/homebrew/sbin
  /usr/local/bin
  /System/Cryptexes/App/usr/bin
  /usr/bin
  /bin
  /usr/sbin
  /sbin
  /var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin
  /var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin
  /var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin
  /pkg/env/global/bin
  /Library/Apple/usr/bin
  /Users/<redacted>/.codex/tmp/arg0/codex-arg0rHEufG
  /opt/homebrew/lib/node_modules/@openai/codex/node_modules/@openai/codex-darwin-arm64/vendor/aarch64-apple-darwin/codex-path
  /opt/homebrew/opt/openjdk@17/bin
  /Users/<redacted>/.rbenv/shims
  /Users/<redacted>/.local/bin
  /Applications/Ghostty.app/Contents/MacOS
  /Users/<redacted>/.orbstack/bin
  /Users/<redacted>/.orbstack/bin

UI Automation (axe)
  Available: Yes
  UI Automation Supported: Yes
  Simulator Video Capture Supported (AXe >= 1.1.0): Yes
  UI-Debugger Guard Mode: error

Incremental Builds
  Enabled: No
  xcodemake Binary Available: No
  Makefile exists (cwd): (not checked: incremental builds disabled)

Mise Integration
  Running under mise: No
  Mise available: Yes

Debugger Backend (DAP)
  lldb-dap available: Yes
  Selected backend: dap

Manifest Tool Inventory
  Total Unique Tools: 82
  Workflow Count: 15
  coverage: 2 tools
  debugging: 8 tools
  device: 15 tools
  doctor: 1 tools
  macos: 13 tools
  project-discovery: 5 tools
  project-scaffolding: 2 tools
  session-management: 5 tools
  simulator-management: 10 tools
  simulator: 20 tools
  swift-package: 8 tools
  ui-automation: 14 tools
  utilities: 1 tools
  workflow-discovery: 1 tools
  xcode-ide: 5 tools

Runtime Tool Registration
  Enabled Workflows: 0
  Registered Tools: 0
  Note: Runtime registry unavailable.

Xcode IDE Bridge (mcpbridge)
  Workflow enabled: No
  mcpbridge path: /Applications/Xcode-26.6.0.app/Contents/Developer/usr/bin/mcpbridge
  Xcode running: true
  Connected: No
  Bridge PID: (none)
  Proxied tools: 0
  Last error: (none)
  Note: Bridge debug tools (status/sync/disconnect) are only registered when debug: true

Tool Availability Summary
  Build Tools: Available
  UI Automation Tools: Available
  Incremental Build Support: Not available

Sentry
  Sentry enabled: Yes

Troubleshooting Tips
  If UI automation tools are not available, install axe: brew tap cameroncooke/axe && brew install axe
  If incremental build support is not available, install xcodemake (https://github.com/cameroncooke/xcodemake) and ensure it is executable and available in your PATH
  To enable xcodemake, set environment variable: export INCREMENTAL_BUILDS_ENABLED=1
  For mise integration, follow instructions in the README.md file

✅ Doctor diagnostics complete

Editor/Client

Codex CLI 0.147.0

MCP Server Version

2.7.0

LLM

OpenAI GPT-5.6 Sol

MCP Configuration

Steps to Reproduce

1. Download and unzip Repro.zip.
2. Run the following command with an available iOS Simulator UDID:

xcodebuildmcp simulator test --project-path Repro.xcodeproj --scheme App --simulator-id <ios-simulator-udid>

3. On 2.7.0, both tests are discovered but the test run fails while resolving the destination.
4. Run the same command with 2.6.2. Both tests pass.
5. Remove WatchTests from testTargets in Repro.xctestplan and run 2.7.0 again. The remaining iOS test passes.

Repro.zip
xcodebuild-invocations.txt

Expected Behavior

The iOS and watchOS tests should run using the selected paired simulators, as they do on 2.6.2.

Actual Behavior

2.7.0 completes build-for-testing, discovers both tests, then fails during test-without-building because it cannot resolve the requested iOS Simulator.

Error Messages

Discovered 2 test(s):
   AppTests/AppTests/testPasses
   WatchTests/WatchTests/testPasses

Errors (1):

  ✗ Unable to find a device matching the provided destination specifier:
    { platform:iOS Simulator, id:<ios-simulator-udid> }

❌ Test failed.