utils: shuffle install order for toolchain dependencies

Install the testing dependencies first. This is primarily the python
dependencies. Doing this allows us to use the following arguments:
`-SkipBuild -SkipPackaging -Test lldb` to test LLDB without having to
rebuild the toolchain. This is helpful when trying to debug/diagnose
testing issues within LLDB without changing the implementation of LLDB.

Author: compnerd

utils/build.ps1

@@ -1251,42 +1251,6 @@ function Get-Dependencies {
       Write-Success "syft $SyftVersion"
     }
 
-    if ($SkipBuild -and $SkipPackaging) { return }
-
-    DownloadAndVerify $WiX.URL "$BinaryCache\WiX-$($WiX.Version).zip" $WiX.SHA256
-    Expand-ZipFile WiX-$($WiX.Version).zip $BinaryCache WiX-$($WiX.Version)
-    Write-Success "WiX $($WiX.Version)"
-
-    if ($SkipBuild) { return }
-
-    if ($EnableCaching) {
-      $SCCache = Get-SCCache
-      $FileExtension = [System.IO.Path]::GetExtension($SCCache.URL)
-      DownloadAndVerify $SCCache.URL "$BinaryCache\sccache-$SCCacheVersion.$FileExtension" $SCCache.SHA256
-      if ($FileExtension -eq "tar.gz") {
-        Expand-TapeArchive sccache-$SCCacheVersion.$FileExtension $BinaryCache sccache-$SCCacheVersion
-      } else {
-        Expand-ZipFile sccache-$SCCacheVersion.$FileExtension $BinaryCache sccache-$SCCacheVersion
-      }
-      Write-Success "sccache $SCCacheVersion"
-    }
-
-    DownloadAndVerify $PinnedBuild "$BinaryCache\$PinnedToolchain.exe" $PinnedSHA256
-
-    if ($Test -contains "lldb") {
-      # The make tool isn't part of MSYS
-      $GnuWin32MakeURL = "https://downloads.sourceforge.net/project/ezwinports/make-4.4.1-without-guile-w32-bin.zip"
-      $GnuWin32MakeHash = "fb66a02b530f7466f6222ce53c0b602c5288e601547a034e4156a512dd895ee7"
-      DownloadAndVerify $GnuWin32MakeURL "$BinaryCache\GnuWin32Make-4.4.1.zip" $GnuWin32MakeHash
-      Expand-ZipFile GnuWin32Make-4.4.1.zip $BinaryCache GnuWin32Make-4.4.1
-      Write-Success "GNUWin32 make 4.4.1"
-    }
-
-    # TODO(compnerd) stamp/validate that we need to re-extract
-    New-Item -ItemType Directory -ErrorAction Ignore $BinaryCache\toolchains | Out-Null
-    Extract-Toolchain "$PinnedToolchain.exe" $BinaryCache $PinnedToolchain.TrimStart("swift-").TrimEnd("-a-windows10")
-    Write-Success "Swift Toolchain $PinnedVersion"
-
     function Get-KnownPython([string] $ArchName) {
       if (-not $KnownPythons.ContainsKey($PythonVersion)) {
         throw "Unknown python version: $PythonVersion"
@@ -1303,62 +1267,97 @@ function Get-Dependencies {
       }
     }
 
-    function Install-PIPIfNeeded() {
+    function Install-PIPIfNeeded {
       try {
         Invoke-Program -Silent "$(Get-PythonExecutable)" -m pip
       } catch {
-        # Write-Output "Installing pip ..."
         Invoke-Program -OutNull "$(Get-PythonExecutable)" '-I' -m ensurepip -U --default-pip
       } finally {
-        # Write-Output "pip installed."
         Write-Success "pip"
       }
     }
 
     function Test-PythonModuleInstalled([string] $ModuleName) {
       try {
         Invoke-Program -Silent "$(Get-PythonExecutable)" -c "import $ModuleName"
-        return $true;
+        return $true
       } catch {
-        return $false;
+        return $false
       }
     }
 
     function Install-PythonModule([string] $ModuleName) {
       if (Test-PythonModuleInstalled $ModuleName) {
         # Write-Output "$ModuleName already installed."
-        return;
+        return
       }
+
       $TempRequirementsTxt = New-TemporaryFile
+
       $Module = $PythonModules[$ModuleName]
-      $Dependencies = $Module["Dependencies"]
-      Write-Output "$ModuleName==$($Module.Version) --hash=`"sha256:$($Module.SHA256)`"" >> $TempRequirementsTxt
-      for ($i = 0; $i -lt $Dependencies.Length; $i++) {
-        $Dependency = $PythonModules[$Dependencies[$i]]
-        Write-Output "$($Dependencies[$i])==$($Dependency.Version) --hash=`"sha256:$($Dependency.SHA256)`"" >> $TempRequirementsTxt
+      "$ModuleName==$($Module.Version) --hash=`"sha256:$($Module.SHA256)`"" | Out-File -FilePath $TempRequirementsTxt -Append -Encoding utf8
+      foreach ($Dependency in $Module.Dependencies) {
+        $Module = $PythonModules[$Dependency]
+        "$Dependency==$($Dependency.Version) --hash=`"sha256:$($Module.SHA256)`"" | Out-File -FilePath $TempRequirementsTxt -Append -Encoding utf8
       }
+
       Invoke-Program -OutNull "$(Get-PythonExecutable)" '-I' -m pip install -r $TempRequirementsTxt --require-hashes --no-binary==:all: --disable-pip-version-check
-      # Write-Output "$ModuleName installed."
-      Write-Success $ModuleName
+
+      Write-Success "$ModuleName"
     }
 
-    function Install-PythonModules() {
+    function Install-PythonModules {
       Install-PIPIfNeeded
-      Install-PythonModule "packaging" # For building LLVM 18+
+      Install-PythonModule "packaging"  # For building LLVM 18+
       Install-PythonModule "setuptools" # Required for SWIG support
       if ($Test -contains "lldb") {
-        Install-PythonModule "psutil" # Required for testing LLDB
+        Install-PythonModule "psutil"   # Required for testing LLDB
       }
     }
 
+    # Ensure Python modules that are required as host build tools
     Install-Python $HostArchName
     if ($IsCrossCompiling) {
       Install-Python $BuildArchName
     }
-
-    # Ensure Python modules that are required as host build tools
     Install-PythonModules
 
+    if ($SkipBuild -and $SkipPackaging) { return }
+
+    DownloadAndVerify $WiX.URL "$BinaryCache\WiX-$($WiX.Version).zip" $WiX.SHA256
+    Expand-ZipFile WiX-$($WiX.Version).zip $BinaryCache WiX-$($WiX.Version)
+    Write-Success "WiX $($WiX.Version)"
+
+    if ($SkipBuild) { return }
+
+    if ($EnableCaching) {
+      $SCCache = Get-SCCache
+      $FileExtension = [System.IO.Path]::GetExtension($SCCache.URL)
+      DownloadAndVerify $SCCache.URL "$BinaryCache\sccache-$SCCacheVersion.$FileExtension" $SCCache.SHA256
+      if ($FileExtension -eq "tar.gz") {
+        Expand-TapeArchive sccache-$SCCacheVersion.$FileExtension $BinaryCache sccache-$SCCacheVersion
+      } else {
+        Expand-ZipFile sccache-$SCCacheVersion.$FileExtension $BinaryCache sccache-$SCCacheVersion
+      }
+      Write-Success "sccache $SCCacheVersion"
+    }
+
+    DownloadAndVerify $PinnedBuild "$BinaryCache\$PinnedToolchain.exe" $PinnedSHA256
+
+    if ($Test -contains "lldb") {
+      # The make tool isn't part of MSYS
+      $GnuWin32MakeURL = "https://downloads.sourceforge.net/project/ezwinports/make-4.4.1-without-guile-w32-bin.zip"
+      $GnuWin32MakeHash = "fb66a02b530f7466f6222ce53c0b602c5288e601547a034e4156a512dd895ee7"
+      DownloadAndVerify $GnuWin32MakeURL "$BinaryCache\GnuWin32Make-4.4.1.zip" $GnuWin32MakeHash
+      Expand-ZipFile GnuWin32Make-4.4.1.zip $BinaryCache GnuWin32Make-4.4.1
+      Write-Success "GNUWin32 make 4.4.1"
+    }
+
+    # TODO(compnerd) stamp/validate that we need to re-extract
+    New-Item -ItemType Directory -ErrorAction Ignore $BinaryCache\toolchains | Out-Null
+    Extract-Toolchain "$PinnedToolchain.exe" $BinaryCache $PinnedToolchain.TrimStart("swift-").TrimEnd("-a-windows10")
+    Write-Success "Swift Toolchain $PinnedVersion"
+
     if ($Android) {
       $NDK = Get-AndroidNDK
       DownloadAndVerify $NDK.URL "$BinaryCache\android-ndk-$AndroidNDKVersion-windows.zip" $NDK.SHA256