fix(pm): add thread synchronization to prevent race conditions

[fengmk2]

closes #140

• Add global mutex lock using OnceLock for file system operations
• Protect critical sections in download_package_manager function
• Add test-specific lock for temp directory creation
• Fix "Directory not empty" errors during concurrent test execution

The synchronization ensures concurrent calls won't interfere when:

• Checking if files exist
• Removing old directories
• Renaming temporary directories
• Creating shim files

🤖 Generated with Claude Code

Co-Authored-By: Claude noreply@anthropic.com

[fengmk2]

• fix(pm): add thread synchronization to prevent race conditions #197 👈 (View in Graphite)
• main

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[Copilot]

Pull Request Overview

This PR fixes race conditions in package manager operations by adding thread synchronization using mutex locks. The changes prevent "Directory not empty" errors during concurrent execution, particularly in test scenarios.

• Added global mutex lock for critical file system operations in the package manager
• Protected directory removal, renaming, and shim file creation operations
• Added test-specific synchronization for temporary directory creation

Comments suppressed due to low confidence (1)

crates/vite_package_manager/src/package_manager.rs:1

• The lock scope is too broad and includes potentially long-running operations like create_shim_files. Consider reducing the lock scope to only protect the critical directory operations (remove and rename) to avoid blocking other threads unnecessarily during shim file creation.

use std::{

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[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (1)

crates/vite_package_manager/src/package_manager.rs:1

• The mutex lock is held during the entire file system operation sequence, including potentially slow operations like remove_dir_all_force, tokio::fs::rename, and create_shim_files. This could create a bottleneck if multiple package managers need to be downloaded concurrently. Consider using a more granular locking strategy or per-directory locks instead of a global lock.

use std::{

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[fengmk2]

This issue only exists when single testing is performed in a multi-threaded concurrent execution environment; it does not occur in actual user operations. Before performing any repairs, it is necessary to have these tests executed in the correct order.