pi-lens/rules/tree-sitter-queries/csharp/no-thread-resume-suspend.yml

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# No Thread.Resume or Thread.Suspend
# Detects usage of deprecated Thread.Resume() and Thread.Suspend()
id: no-thread-resume-suspend
name: Thread.Resume and Thread.Suspend Should Not Be Used
severity: error
category: reliability
defect_class: correctness
inline_tier: blocking
language: csharp

message: "{{METHOD}} should not be used — deprecated and causes deadlocks"

description: |
  Thread.Resume() and Thread.Suspend() are deprecated and dangerous.
  They can cause deadlocks if the thread holds locks while suspended.
  Use synchronization primitives like Monitor, Mutex, or Semaphore.

  ✅ FIX: Use proper synchronization primitives

  ```csharp
  await semaphore.WaitAsync();
  try {
      // Work...
  } finally {
      semaphore.Release();
  }
  ```

query: |
  (invocation_expression
    function: (member_access_expression
      expression: (identifier) @OBJ (#eq? @OBJ "Thread")
      name: (identifier) @METHOD (#match? @METHOD "^(Resume|Suspend)$")) @CALL)

metavars:
  - OBJ
  - METHOD
  - CALL

tags:
  - reliability
  - csharp
  - multi-threading
  - deadlock
  - deprecated

examples:
  bad: |
    thread.Suspend();  // BAD - deprecated, deadlock risk
    // ... work ...
    thread.Resume();   // BAD

  good: |
    using (var semaphore = new SemaphoreSlim(1)) {
        await semaphore.WaitAsync();  // GOOD - proper sync
        // ... work ...
        semaphore.Release();
    }

has_fix: false