Fix xdist issue with multiple approaches

- Use PYTEST_DISABLE_PLUGIN_AUTOLOAD environment variable (recommended in CLAUDE.md)
- Use -p no:xdist flag to explicitly disable the plugin
- Add --no-cov to avoid coverage plugin issues
- Add test-stdio-simple.ps1 to try different methods of disabling xdist

Author: felixweinberger

scripts/windows-debug/test-stdio-flakiness-200-runs.ps1

@@ -6,6 +6,9 @@ Write-Host "Running test_stdio_context_manager_exiting 200 times to detect flaki
 Write-Host "Test: tests/client/test_stdio.py::test_stdio_context_manager_exiting" -ForegroundColor Yellow
 Write-Host ""
 
+# Disable pytest plugin autoload to avoid xdist issues
+$env:PYTEST_DISABLE_PLUGIN_AUTOLOAD = ""
+
 $startTime = Get-Date
 $count = 0
 $failures = 0
@@ -14,7 +17,10 @@ $failedRuns = @()
 for ($i = 1; $i -le 200; $i++) {
     Write-Host "Run $i of 200..." -NoNewline
 
-    $output = uv run --frozen pytest tests/client/test_stdio.py::test_stdio_context_manager_exiting -xvs -n 0 2>&1
+    $output = & {
+        $env:PYTEST_DISABLE_PLUGIN_AUTOLOAD = ""
+        uv run --frozen pytest tests/client/test_stdio.py::test_stdio_context_manager_exiting -xvs --no-cov -p no:xdist 2>&1
+    }
     $exitCode = $LASTEXITCODE
 
     if ($exitCode -ne 0) {
@@ -41,4 +47,7 @@ if ($failures -gt 0) {
     Write-Host "Failed on runs: $($failedRuns -join ', ')" -ForegroundColor Red
 }
 Write-Host "Duration: $($duration.ToString())"
-Write-Host "Failure rate: $([math]::Round(($failures / 200) * 100, 2))%"
+Write-Host "Failure rate: $([math]::Round(($failures / 200) * 100, 2))%"
+
+# Clean up environment variable
+Remove-Item Env:PYTEST_DISABLE_PLUGIN_AUTOLOAD -ErrorAction SilentlyContinue

scripts/windows-debug/test-stdio-flakiness-until-failure.ps1

@@ -7,14 +7,20 @@ Write-Host "Test: tests/client/test_stdio.py::test_stdio_context_manager_exiting
 Write-Host "Press Ctrl+C to stop" -ForegroundColor Gray
 Write-Host ""
 
+# Disable pytest plugin autoload to avoid xdist issues
+$env:PYTEST_DISABLE_PLUGIN_AUTOLOAD = ""
+
 $startTime = Get-Date
 $i = 0
 
 while ($true) {
     $i++
     Write-Host "Run $i..." -NoNewline
 
-    $output = uv run --frozen pytest tests/client/test_stdio.py::test_stdio_context_manager_exiting -xvs -n 0 2>&1
+    $output = & {
+        $env:PYTEST_DISABLE_PLUGIN_AUTOLOAD = ""
+        uv run --frozen pytest tests/client/test_stdio.py::test_stdio_context_manager_exiting -xvs --no-cov -p no:xdist 2>&1
+    }
     $exitCode = $LASTEXITCODE
 
     if ($exitCode -ne 0) {
@@ -39,4 +45,7 @@ while ($true) {
 }
 
 Write-Host ""
-Write-Host "Exiting after failure detection." -ForegroundColor Cyan
+Write-Host "Exiting after failure detection." -ForegroundColor Cyan
+
+# Clean up environment variable
+Remove-Item Env:PYTEST_DISABLE_PLUGIN_AUTOLOAD -ErrorAction SilentlyContinue

scripts/windows-debug/test-stdio-simple.ps1

@@ -0,0 +1,54 @@
+#!/usr/bin/env pwsh
+# Simple script to run the test without xdist
+# Usage: .\test-stdio-simple.ps1
+
+Write-Host "Running test_stdio_context_manager_exiting with xdist disabled..." -ForegroundColor Cyan
+Write-Host ""
+
+# Method 1: Using environment variable (recommended in CLAUDE.md)
+Write-Host "Method 1: Using PYTEST_DISABLE_PLUGIN_AUTOLOAD environment variable" -ForegroundColor Yellow
+$env:PYTEST_DISABLE_PLUGIN_AUTOLOAD = ""
+uv run --frozen pytest tests/client/test_stdio.py::test_stdio_context_manager_exiting -xvs
+$exitCode1 = $LASTEXITCODE
+Remove-Item Env:PYTEST_DISABLE_PLUGIN_AUTOLOAD -ErrorAction SilentlyContinue
+
+if ($exitCode1 -eq 0) {
+    Write-Host "Method 1: PASSED" -ForegroundColor Green
+} else {
+    Write-Host "Method 1: FAILED with exit code $exitCode1" -ForegroundColor Red
+}
+
+Write-Host ""
+
+# Method 2: Using -p no:xdist to disable the plugin
+Write-Host "Method 2: Using -p no:xdist flag" -ForegroundColor Yellow
+uv run --frozen pytest tests/client/test_stdio.py::test_stdio_context_manager_exiting -xvs -p no:xdist
+$exitCode2 = $LASTEXITCODE
+
+if ($exitCode2 -eq 0) {
+    Write-Host "Method 2: PASSED" -ForegroundColor Green
+} else {
+    Write-Host "Method 2: FAILED with exit code $exitCode2" -ForegroundColor Red
+}
+
+Write-Host ""
+
+# Method 3: Override addopts from pyproject.toml
+Write-Host "Method 3: Overriding pytest addopts" -ForegroundColor Yellow
+uv run --frozen pytest tests/client/test_stdio.py::test_stdio_context_manager_exiting -xvs -o addopts=""
+$exitCode3 = $LASTEXITCODE
+
+if ($exitCode3 -eq 0) {
+    Write-Host "Method 3: PASSED" -ForegroundColor Green
+} else {
+    Write-Host "Method 3: FAILED with exit code $exitCode3" -ForegroundColor Red
+}
+
+Write-Host ""
+Write-Host "========== SUMMARY ==========" -ForegroundColor Cyan
+if ($exitCode1 -eq 0 -or $exitCode2 -eq 0 -or $exitCode3 -eq 0) {
+    Write-Host "At least one method succeeded!" -ForegroundColor Green
+    Write-Host "Use the successful method in your testing."
+} else {
+    Write-Host "All methods failed. The test may have a different issue." -ForegroundColor Red
+}

scripts/windows-debug/test-stdio-verbose-debug.ps1

@@ -8,19 +8,23 @@ Write-Host ""
 # Set environment variables for debugging
 $env:PYTHONFAULTHANDLER = "1"
 $env:PYTEST_CURRENT_TEST = "1"
+$env:PYTEST_DISABLE_PLUGIN_AUTOLOAD = ""
 
 Write-Host "Environment variables set:" -ForegroundColor Yellow
 Write-Host "  PYTHONFAULTHANDLER = 1 (enables Python fault handler)"
+Write-Host "  PYTEST_DISABLE_PLUGIN_AUTOLOAD = '' (disables pytest plugin autoload)"
 Write-Host ""
 
 Write-Host "Running test with maximum verbosity..." -ForegroundColor Cyan
 Write-Host ""
 
 # Run the test with all debugging options
+$env:PYTEST_DISABLE_PLUGIN_AUTOLOAD = ""
 uv run --frozen pytest `
     tests/client/test_stdio.py::test_stdio_context_manager_exiting `
     -xvs `
-    -n 0 `
+    --no-cov `
+    -p no:xdist `
     --log-cli-level=DEBUG `
     --log-cli-format="%(asctime)s [%(levelname)s] %(name)s: %(message)s" `
     --capture=no `
@@ -38,4 +42,5 @@ if ($exitCode -eq 0) {
 
 # Clean up environment variables
 Remove-Item Env:PYTHONFAULTHANDLER -ErrorAction SilentlyContinue
-Remove-Item Env:PYTEST_CURRENT_TEST -ErrorAction SilentlyContinue
+Remove-Item Env:PYTEST_CURRENT_TEST -ErrorAction SilentlyContinue
+Remove-Item Env:PYTEST_DISABLE_PLUGIN_AUTOLOAD -ErrorAction SilentlyContinue