Alternative PowerShell script. Fix missing pop in BAT file (in case of fatal...

Alternative PowerShell script. Fix missing pop in BAT file (in case of fatal error). Exit gracefully. Force SDK Path. (#5484)

bin/flutter.ps1

+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# How to use this script:
+#  - Allow the execution of PowerShell scripts (ByPass, etc.), for example:
+#     Set-ExecutionPolicy Unrestricted
+#  - Invoke any flutter command: Flutter.ps1 doctor
+#  - Force the path to Dart SDK: Flutter.ps1 -DartPath "c:\tools\dart\"
+
+[CmdletBinding()]
+param (
+  [Parameter(Mandatory=$False)]
+  [string]$DartPath,
+  [Parameter(Mandatory=$False)]
+  [switch]$Diag,
+  [parameter(mandatory=$False, position=1, ValueFromRemainingArguments=$true)]
+  $Remaining
+)
+
+# This function creates a snapshot of the latest version of flutter framework
+function Do-Snapshot
+{
+	Set-Location $flutterToolsDir
+	Write-Host "Info: Updating flutter tool..."
+	Invoke-Expression "pub.bat get $(&{If($Diag) {"--verbose"}})" 
+	Set-Location $flutterDir
+	# Allows us to check if sky_engine's REVISION is correct
+	Write-Host "Info: Updating sky engine..."
+	Invoke-Expression "pub.bat get $(&{If($Diag) {"--verbose"}})"
+	Set-Location $flutterRoot
+	Invoke-Expression "$dartExe --snapshot=`"$snapshotPath`" `"$scriptPath`" --packages=`"$flutterToolsDir\.packages`""
+	$revision | Out-File  $stampPath
+}
+
+# Save the current location
+Push-Location
+
+# Get the parent directory
+$scriptPath = split-path -parent $MyInvocation.MyCommand.Definition
+$flutterRoot = (get-item $scriptPath ).parent.FullName
+
+$flutterToolsDir = $flutterRoot + '\packages\flutter_tools'
+$flutterDir = $flutterRoot + '\packages\flutter'
+$snapshotPath = $flutterRoot + '\bin\cache\flutter_tools.snapshot'
+$stampPath = $flutterRoot + '\bin\cache\flutter_tools.stamp'
+$scriptPath = $flutterToolsDir + '\bin\flutter_tools.dart'
+$dartExe = [io.path]::combine($DartPath, 'dart.exe')
+
+# Set current working directory to the flutter directory
+Set-Location $flutterRoot
+
+# Test if Git is available on the Host
+if ((Get-Command "git.exe" -ErrorAction SilentlyContinue) -eq $null) { 
+   Write-Host "Error: Unable to find git.exe in your PATH"
+   Pop-Location
+   exit
+}
+# Test if the flutter directory is a git clone (otherwise git rev-parse HEAD would fail)
+if (-not (Test-Path '.git')) {
+   Write-Host "Error: The flutter directory is not a clone of the GH project"
+   Pop-Location
+   exit
+}
+# Test if pub.bat is available on the Host
+if ((Get-Command "pub.bat" -ErrorAction SilentlyContinue) -eq $null) { 
+   Write-Host "Error: Unable to find Dart SDK in your PATH"
+   Pop-Location
+   exit
+}
+
+# Check if the snapshot version is out-of-date.
+$revision = Invoke-Expression "git rev-parse HEAD"
+if ( (-not (Test-Path $snapshotPath)) -Or (-not (Test-Path $stampPath)) ) {
+	Write-Host "Info: Snapshot doesn't exist"
+	Do-Snapshot
+}
+$stampValue = Get-Content $stampPath | Where-Object {$_ -match '\S'}
+if ($stampValue -ne $revision) {
+	Write-Host "Info: Timestamp differs from revision"
+	Do-Snapshot
+}
+$yamltLastWriteTime = (ls "$flutterToolsDir\pubspec.yaml").LastWriteTime
+$locktLastWriteTime = (ls "$flutterToolsDir\pubspec.lock").LastWriteTime
+if ($locktLastWriteTime -lt $yamltLastWriteTime) {
+	Write-Host "Info: Mismatch between yaml and lock files"
+	Do-Snapshot
+}
+
+# Go back to last working directory
+Pop-Location
+Invoke-Expression "$dartExe `"$snapshotPath`" $Remaining"
+
+# The VM exits with code 253 if the snapshot version is out-of-date.
+if ($LASTEXITCODE -eq 253) {
+	Write-Host "Info: VM exited with code 253, we need to snapshot it again."
+	Invoke-Expression "$dartExe --snapshot=`"$snapshotPath`" `"$scriptPath`" --packages=`"$flutterToolsDir\.packages`""
+	Invoke-Expression "$dartExe `"$snapshotPath`" $Remaining"
+}