windows/bootstrap: skip winget; install portable MinGit and Go

DesktopAppInstaller on this host returns 0x8a15000f with an empty
winget index; source reset does not recover it. Fetch MinGit and the
go.dev windows-amd64 zip into LOCALAPPDATA instead.

windows/bootstrap.ps1

@@ -11,65 +11,74 @@ $Dest = Join-Path $env:LOCALAPPDATA 'rclone-dropbox-bisync'
 $Dropbox = 'D:\Dropbox'
 $Workdir = 'D:\rclone-bisync'
 
-function Refresh-Path {
+# Do not use winget: 0x8a15000f (empty source cache) is common and not recoverable
-    $env:Path = [Environment]::GetEnvironmentVariable('Path', 'Machine') + ';' +
+# from this script. Fetch portable MinGit + Go into LOCALAPPDATA instead.
-        [Environment]::GetEnvironmentVariable('Path', 'User')
+$Tools = Join-Path $Dest 'tools'
+
+function Prepend-UserPath($Dir) {
+    $userPath = [Environment]::GetEnvironmentVariable('Path', 'User')
+    if ([string]::IsNullOrEmpty($userPath)) { $userPath = '' }
+    if ($userPath -notlike "*$Dir*") {
+        [Environment]::SetEnvironmentVariable('Path', $(if ($userPath) { "$Dir;$userPath" } else { $Dir }), 'User')
+    }
+    if ($env:Path -notlike "*$Dir*") { $env:Path = "$Dir;$env:Path" }
 }
 
-# 0x8a15000f: winget source index missing/corrupt (common on a fresh DesktopAppInstaller).
+function Get-File($Url, $Out) {
-function Repair-WingetSource {
+    [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
-    if ($script:WingetSourceRepaired) { return }
+    Invoke-WebRequest -Uri $Url -OutFile $Out -UseBasicParsing
-    $winget = Get-Command winget -ErrorAction SilentlyContinue
-    if (-not $winget) { return }
-    $prev = $ErrorActionPreference
-    $ErrorActionPreference = 'Continue'
-    try {
-        & winget source reset --force --disable-interactivity 2>&1 | Out-Null
-        & winget source update --disable-interactivity 2>&1 | Out-Null
-    } finally {
-        $ErrorActionPreference = $prev
-    }
-    $script:WingetSourceRepaired = $true
 }
 
-function Install-WithWinget($WingetId) {
+function Ensure-Git {
-    Repair-WingetSource
+    if (Get-Command git -ErrorAction SilentlyContinue) { return }
-    $wingetArgs = @(
+    $root = Join-Path $Tools 'mingit'
-        'install', '-e', '--id', $WingetId,
+    $cmd = Join-Path $root 'cmd'
-        '--accept-package-agreements', '--accept-source-agreements',
+    if (-not (Test-Path (Join-Path $cmd 'git.exe'))) {
-        '--disable-interactivity', '--source', 'winget'
+        Write-Host 'Fetching MinGit...'
-    )
+        $rel = Invoke-RestMethod -Uri 'https://api.github.com/repos/git-for-windows/git/releases/latest'
-    $prev = $ErrorActionPreference
+        $asset = $rel.assets |
-    $ErrorActionPreference = 'Continue'
+            Where-Object { $_.name -match '^MinGit-.+-64-bit\.zip$' -and $_.name -notmatch 'busybox' } |
-    try {
+            Select-Object -First 1
-        & winget @wingetArgs
+        if (-not $asset) { throw 'No MinGit-*-64-bit.zip on git-for-windows latest release' }
-        if ($LASTEXITCODE -eq 0) { return }
+        $zip = Join-Path $env:TEMP $asset.name
-        # Index still empty: reset once more, then retry without pinning the source
+        Get-File $asset.browser_download_url $zip
-        # (some hosts only have msstore until cdn.winget.microsoft.com is reachable).
+        New-Item -ItemType Directory -Force -Path $root | Out-Null
-        & winget source reset --force --disable-interactivity 2>&1 | Out-Null
+        Expand-Archive -Path $zip -DestinationPath $root -Force
-        & winget source update --disable-interactivity 2>&1 | Out-Null
-        & winget install -e --id $WingetId --accept-package-agreements --accept-source-agreements --disable-interactivity
-        if ($LASTEXITCODE -eq 0) { return }
-    } finally {
-        $ErrorActionPreference = $prev
     }
-    throw "winget failed to install $WingetId (exit $LASTEXITCODE / 0x8a15000f = empty source cache). Run: winget source reset --force; winget source update"
+    Prepend-UserPath $cmd
-}
+    if (-not (Get-Command git -ErrorAction SilentlyContinue)) {
-
+        throw "git.exe missing under $cmd"
-function Ensure-Cmd($Name, $WingetId) {
-    if (Get-Command $Name -ErrorAction SilentlyContinue) { return }
-    if (-not (Get-Command winget -ErrorAction SilentlyContinue)) {
-        throw "Need $Name on PATH (or winget to install $WingetId)"
-    }
-    Install-WithWinget $WingetId
-    Refresh-Path
-    if (-not (Get-Command $Name -ErrorAction SilentlyContinue)) {
-        throw "$Name still missing after winget install $WingetId; open a new PowerShell and retry"
     }
 }
 
-Ensure-Cmd git Git.Git
+function Ensure-Go {
-Ensure-Cmd go GoLang.Go
+    if (Get-Command go -ErrorAction SilentlyContinue) { return }
+    $root = Join-Path $Tools 'go'
+    $bin = Join-Path $root 'go\bin'
+    if (-not (Test-Path (Join-Path $bin 'go.exe'))) {
+        Write-Host 'Fetching Go...'
+        $dl = Invoke-RestMethod -Uri 'https://go.dev/dl/?mode=json'
+        $file = $null
+        foreach ($rel in $dl) {
+            $file = $rel.files |
+                Where-Object { $_.os -eq 'windows' -and $_.arch -eq 'amd64' -and $_.kind -eq 'archive' } |
+                Select-Object -First 1
+            if ($file) { break }
+        }
+        if (-not $file) { throw 'No windows-amd64 Go archive on go.dev/dl' }
+        $zip = Join-Path $env:TEMP $file.filename
+        Get-File "https://go.dev/dl/$($file.filename)" $zip
+        New-Item -ItemType Directory -Force -Path $root | Out-Null
+        Expand-Archive -Path $zip -DestinationPath $root -Force
+    }
+    Prepend-UserPath $bin
+    if (-not (Get-Command go -ErrorAction SilentlyContinue)) {
+        throw "go.exe missing under $bin"
+    }
+}
+
+Ensure-Git
+Ensure-Go
 
 New-Item -ItemType Directory -Force -Path $Src, (Join-Path $Dest 'bin') | Out-Null
 if (-not (Test-Path (Join-Path $Src 'packaging\.git'))) {