Add Python fallback to dev check

scripts/dev_check.ps1

@@ -29,14 +29,132 @@ function Invoke-Check {
     }
 }
 
+function Invoke-PytestCandidate {
+    param(
+        [Parameter(Mandatory = $true)]
+        [string]$Label,
+
+        [Parameter(Mandatory = $true)]
+        [string]$Executable,
+
+        [Parameter(Mandatory = $true)]
+        [string[]]$Arguments,
+
+        [bool]$RequireFile = $false
+    )
+
+    $commandText = "$Executable $($Arguments -join ' ')"
+    Write-Host ""
+    Write-Host "Trying: $Label"
+    Write-Host $commandText
+
+    if ($RequireFile -and -not (Test-Path -LiteralPath $Executable)) {
+        return @{
+            Started = $false
+            Success = $false
+            Reason = "executable not found"
+        }
+    }
+
+    try {
+        $global:LASTEXITCODE = 0
+        $output = & $Executable @Arguments 2>&1
+        $exitCode = $LASTEXITCODE
+        if ($output) {
+            $output | ForEach-Object { Write-Host $_ }
+        }
+
+        $outputText = ($output | Out-String)
+        if ($exitCode -ne 0 -and $outputText -match "No module named pytest") {
+            return @{
+                Started = $false
+                Success = $false
+                Reason = "pytest module not found"
+            }
+        }
+
+        if ($exitCode -eq 0) {
+            return @{
+                Started = $true
+                Success = $true
+                Reason = "pytest completed successfully"
+            }
+        }
+
+        return @{
+            Started = $true
+            Success = $false
+            Reason = "pytest failed with exit code $exitCode"
+        }
+    }
+    catch {
+        return @{
+            Started = $false
+            Success = $false
+            Reason = $_.Exception.Message
+        }
+    }
+}
+
+function Invoke-Pytest {
+    $codexPython = "C:\Users\tamaru\.cache\codex-runtimes\codex-primary-runtime\dependencies\python\python.exe"
+    $basetemp = Join-Path $env:TEMP "utr_lan_pytest_tmp"
+    $attempts = @()
+    $candidates = @(
+        @{
+            Label = "py -m pytest tests"
+            Executable = "py"
+            Arguments = @("-m", "pytest", "tests")
+            RequireFile = $false
+        },
+        @{
+            Label = "python -m pytest tests"
+            Executable = "python"
+            Arguments = @("-m", "pytest", "tests")
+            RequireFile = $false
+        },
+        @{
+            Label = "Codex bundled Python"
+            Executable = $codexPython
+            Arguments = @("-m", "pytest", "tests", "-p", "no:cacheprovider", "--basetemp", $basetemp)
+            RequireFile = $true
+        }
+    )
+
+    foreach ($candidate in $candidates) {
+        $label = $candidate["Label"]
+        $executable = $candidate["Executable"]
+        $arguments = $candidate["Arguments"]
+        $requireFile = $candidate["RequireFile"]
+        $result = Invoke-PytestCandidate -Label $label -Executable $executable -Arguments $arguments -RequireFile $requireFile
+
+        $attempts += ("- {0}: {1}" -f $label, $result["Reason"])
+
+        if ($result["Started"] -and $result["Success"]) {
+            $global:LASTEXITCODE = 0
+            return
+        }
+
+        if ($result["Started"] -and -not $result["Success"]) {
+            throw $result["Reason"]
+        }
+    }
+
+    $notExecutedText = "pytest" + [string][char]0x672A + [string][char]0x5B9F + [string][char]0x884C
+    Write-Host $notExecutedText -ForegroundColor Red
+    Write-Host "Tried:"
+    $attempts | ForEach-Object { Write-Host $_ }
+    throw "pytest was not executed"
+}
+
 Push-Location $repoRoot
 try {
     Invoke-Check "git status --short" {
         git status --short
     }
 
-    Invoke-Check "py -m pytest tests" {
-        py -m pytest tests
+    Invoke-Check "pytest" {
+        Invoke-Pytest
     }
 
     $scanScript = Join-Path $PSScriptRoot ("sec" + "ret_scan.ps1")