Repository: flutter
Issue: [flutter_tools] flutter channel should check out latest release on channel
Labels: tool,a: quality,P3,team-tool,triaged-tool

So a weird thing happened. I've been on the `master` channel on my Windows machine, but wanted to check something out about the latest `dev` channel release. 

I last ran `flutter upgrade` on this machine last Friday (so the bits were _fresh_), but when I ran `flutter channel dev`, it took me back to v0.5.7. I was expecting it to take me to the last dev channel version released. 

As a result of it pushing me back to 0.5.7, `flutter upgrade` failed because of bug https://github.com/flutter/flutter/issues/14578. 

I'd love to understand why switching channel could throw me back eight months in time? This might perhaps also explain why a good number of users show up in the beta channel running 0.9.4 when all other pre-1.0 releases have negligible usage. 

```
[C:\Users\timsneath] flutter channel dev
  ╔════════════════════════════════════════════════════════════════════════════╗
  ║ A new version of Flutter is available!                                     ║
  ║                                                                            ║
  ║ To update to the latest version, run "flutter upgrade".                    ║
  ╚════════════════════════════════════════════════════════════════════════════╝


Switching to flutter channel 'dev'...
git: From https://github.com/flutter/flutter
git:    7390cc5cd..035e0765c  master     -> origin/master
git: Your branch is behind 'origin/dev' by 1934 commits, and can be fast-forwarded.
git:   (use "git pull" to update your local branch)
git: Switched to branch 'dev'

[C:\Users\timsneath] flutter upgrade
Checking Dart SDK version...
Downloading Dart SDK from Flutter engine 6fe748490d1772d72274bf8b9efb72c5c2160237...
Unzipping Dart SDK...
Updating flutter tool...
Upgrading Flutter from c:\git\flutter...
Checking out files:  21% (508/2404)
Checking out files:  22% (529/2404)
Checking out files:  23% (553/2404)
Checking out files:  24% (577/2404)
Checking out files:  25% (601/2404)
Checking out files:  26% (626/2404)
Checking out files:  27% (650/2404)
Checking out files:  28% (674/2404)
Checking out files:  29% (698/2404)
Checking out files:  30% (722/2404)
Checking out files:  31% (746/2404)
Checking out files:  32% (770/2404)
Checking out files:  33% (794/2404)
Checking out files:  34% (818/2404)
Checking out files:  35% (842/2404)
Checking out files:  36% (866/2404)
Checking out files:  37% (890/2404)
Checking out files:  38% (914/2404)
Checking out files:  38% (935/2404)
Checking out files:  39% (938/2404)
Checking out files:  40% (962/2404)
Checking out files:  41% (986/2404)
Checking out files:  42% (1010/2404)
Checking out files:  43% (1034/2404)
Checking out files:  44% (1058/2404)
Checking out files:  45% (1082/2404)
Checking out files:  46% (1106/2404)
Checking out files:  47% (1130/2404)
Checking out files:  48% (1154/2404)
Checking out files:  49% (1178/2404)
Checking out files:  50% (1202/2404)
Checking out files:  51% (1227/2404)
Checking out files:  52% (1251/2404)
Checking out files:  53% (1275/2404)
Checking out files:  54% (1299/2404)
Checking out files:  54% (1322/2404)
Checking out files:  55% (1323/2404)
Checking out files:  56% (1347/2404)
Checking out files:  57% (1371/2404)
Checking out files:  58% (1395/2404)
Checking out files:  59% (1419/2404)
Checking out files:  60% (1443/2404)
Checking out files:  61% (1467/2404)
Checking out files:  62% (1491/2404)
Checking out files:  63% (1515/2404)
Checking out files:  64% (1539/2404)
Checking out files:  65% (1563/2404)
Checking out files:  66% (1587/2404)
Checking out files:  67% (1611/2404)
Checking out files:  68% (1635/2404)
Checking out files:  69% (1659/2404)
Checking out files:  70% (1683/2404)
Checking out files:  71% (1707/2404)
Checking out files:  72% (1731/2404)
Checking out files:  72% (1737/2404)
Checking out files:  73% (1755/2404)
Checking out files:  74% (1779/2404)
Checking out files:  75% (1803/2404)
Checking out files:  76% (1828/2404)
Checking out files:  77% (1852/2404)
Checking out files:  78% (1876/2404)
Checking out files:  79% (1900/2404)
Checking out files:  80% (1924/2404)
Checking out files:  81% (1948/2404)
Checking out files:  82% (1972/2404)
Checking out files:  83% (1996/2404)
Checking out files:  84% (2020/2404)
Checking out files:  85% (2044/2404)
Checking out files:  86% (2068/2404)
Checking out files:  87% (2092/2404)
Checking out files:  88% (2116/2404)
Checking out files:  89% (2140/2404)
Checking out files:  90% (2164/2404)
Checking out files:  90% (2172/2404)
Checking out files:  91% (2188/2404)
Checking out files:  92% (2212/2404)
Checking out files:  93% (2236/2404)
Checking out files:  94% (2260/2404)
Checking out files:  95% (2284/2404)
Checking out files:  96% (2308/2404)
Checking out files:  97% (2332/2404)
Checking out files:  98% (2356/2404)
Checking out files:  99% (2380/2404)
Checking out files: 100% (2404/2404)
Checking out files: 100% (2404/2404), done.
Updating 66091f969..8661d8aec
 .../src/main/res/drawable/launch_background.xml    |     0
 .../app/src/main/res/mipmap-hdpi/ic_launcher.png   |   Bin
 .../app/src/main/res/mipmap-mdpi/ic_launcher.png   |   Bin
 .../app/src/main/res/mipmap-xhdpi/ic_launcher.png  |   Bin
 .../app/src/main/res/mipmap-xxhdpi/ic_launcher.png |   Bin
 .../src/main/res/mipmap-xxxhdpi/ic_launcher.png    |   Bin
 .../android}/app/src/main/res/values/styles.xml    |     0
 .../macrobenchmarks/android}/gradle.properties     |     0
 .../macrobenchmarks/android}/settings.gradle       |     0
 .../ios}/Flutter/AppFrameworkInfo.plist            |     0
 .../macrobenchmarks/ios}/Flutter/Debug.xcconfig    |     0
 .../macrobenchmarks/ios}/Flutter/Release.xcconfig  |     0
 .../project.xcworkspace/contents.xcworkspacedata   |     0
 .../Runner.xcworkspace/contents.xcworkspacedata    |     0
 .../macrobenchmarks/ios}/Runner/AppDelegate.h      |     0
 .../macrobenchmarks/ios}/Runner/AppDelegate.m      |     0
 .../AppIcon.appiconset/Contents.json               |     0
 .../AppIcon.appiconset/Icon-App-1024x1024@1x.png   |   Bin
 .../AppIcon.appiconset/Icon-App-20x20@1x.png       |   Bin
 .../AppIcon.appiconset/Icon-App-20x20@2x.png       |   Bin
 .../AppIcon.appiconset/Icon-App-20x20@3x.png       |   Bin
 .../AppIcon.appiconset/Icon-App-29x29@1x.png       |   Bin
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 .../AppIcon.appiconset/Icon-App-29x29@3x.png       |   Bin
 .../AppIcon.appiconset/Icon-App-40x40@1x.png       |   Bin
 .../AppIcon.appiconset/Icon-App-40x40@2x.png       |   Bin
 .../AppIcon.appiconset/Icon-App-40x40@3x.png       |   Bin
 .../AppIcon.appiconset/Icon-App-60x60@2x.png       |   Bin
 .../AppIcon.appiconset/Icon-App-60x60@3x.png       |   Bin
 .../AppIcon.appiconset/Icon-App-76x76@1x.png       |   Bin
 .../AppIcon.appiconset/Icon-App-76x76@2x.png       |   Bin
 .../AppIcon.appiconset/Icon-App-83.5x83.5@2x.png   |   Bin
 .../LaunchImage.imageset/Contents.json             |     0
 .../LaunchImage.imageset/LaunchImage.png           |   Bin
 .../LaunchImage.imageset/LaunchImage@2x.png        |   Bin
 .../LaunchImage.imageset/LaunchImage@3x.png        |   Bin
 .../Assets.xcassets/LaunchImage.imageset/README.md |     0
 .../ios}/Runner/Base.lproj/LaunchScreen.storyboard |     0
 .../ios}/Runner/Base.lproj/Main.storyboard         |     0
 .../benchmarks/macrobenchmarks/ios}/Runner/main.m  |     0
 .../app/src/main/res/mipmap-hdpi/ic_launcher.png   |   Bin 0 -> 544 bytes
 .../app/src/main/res/mipmap-mdpi/ic_launcher.png   |   Bin 0 -> 442 bytes
 .../app/src/main/res/mipmap-xhdpi/ic_launcher.png  |   Bin 0 -> 721 bytes
 .../app/src/main/res/mipmap-xxhdpi/ic_launcher.png |   Bin 0 -> 1031 bytes
 .../src/main/res/mipmap-xxxhdpi/ic_launcher.png    |   Bin 0 -> 1443 bytes
 .../android/gradle.properties                      |     0
 .../android_views/ios}/.gitignore                  |     0
 .../xcshareddata/xcschemes/Runner.xcscheme         |     0
 .../ios_host_app/Flutter/.gitkeep                  |     0
 packages/flutter/test/widgets/inherited_model.dart |     0
 .../.idea/libraries/Dart_SDK.xml.tmpl              |     0
 .../.idea/libraries/Flutter_for_Android.xml.tmpl   |     0
 .../.idea/runConfigurations/main_dart.xml.tmpl     |     0
 .../{create => app}/.idea/workspace.xml.tmpl       |     0
 .../java/androidIdentifier/MainActivity.java.tmpl  |     0
 .../app/src/main/res/mipmap-hdpi/ic_launcher.png   |   Bin 0 -> 544 bytes
 .../app/src/main/res/mipmap-mdpi/ic_launcher.png   |   Bin 0 -> 442 bytes
 .../app/src/main/res/mipmap-xhdpi/ic_launcher.png  |   Bin 0 -> 721 bytes
 .../app/src/main/res/mipmap-xxhdpi/ic_launcher.png |   Bin 0 -> 1031 bytes
 .../src/main/res/mipmap-xxxhdpi/ic_launcher.png    |   Bin 0 -> 1443 bytes
 .../ios-swift.tmpl/Runner/AppDelegate.swift        |     0
 .../ios-swift.tmpl/Runner/Runner-Bridging-Header.h |     0
 .../ios.tmpl/Flutter/AppFrameworkInfo.plist}       |     0
 .../AppIcon.appiconset/Icon-App-1024x1024@1x.png   |   Bin 0 -> 11112 bytes
 .../AppIcon.appiconset/Icon-App-20x20@1x.png       |   Bin 0 -> 564 bytes
 .../AppIcon.appiconset/Icon-App-20x20@2x.png       |   Bin 0 -> 1283 bytes
 .../AppIcon.appiconset/Icon-App-20x20@3x.png       |   Bin 0 -> 1588 bytes
 .../AppIcon.appiconset/Icon-App-29x29@1x.png       |   Bin 0 -> 1025 bytes
 .../AppIcon.appiconset/Icon-App-29x29@2x.png       |   Bin 0 -> 1716 bytes
 .../AppIcon.appiconset/Icon-App-29x29@3x.png       |   Bin 0 -> 1920 bytes
 .../AppIcon.appiconset/Icon-App-40x40@1x.png       |   Bin 0 -> 1283 bytes
 .../AppIcon.appiconset/Icon-App-40x40@2x.png       |   Bin 0 -> 1895 bytes
 .../AppIcon.appiconset/Icon-App-40x40@3x.png       |   Bin 0 -> 2665 bytes
 .../AppIcon.appiconset/Icon-App-60x60@2x.png       |   Bin 0 -> 2665 bytes
 .../AppIcon.appiconset/Icon-App-60x60@3x.png       |   Bin 0 -> 3831 bytes
 .../AppIcon.appiconset/Icon-App-76x76@1x.png       |   Bin 0 -> 1888 bytes
 .../AppIcon.appiconset/Icon-App-76x76@2x.png       |   Bin 0 -> 3294 bytes
 .../AppIcon.appiconset/Icon-App-83.5x83.5@2x.png   |   Bin 0 -> 3612 bytes
 .../LaunchImage.imageset/LaunchImage.png           |   Bin 0 -> 68 bytes
 .../LaunchImage.imageset/LaunchImage@2x.png        |   Bin 0 -> 68 bytes
 .../LaunchImage.imageset/LaunchImage@3x.png        |   Bin 0 -> 68 bytes
 .../ios.tmpl/Runner/Info.plist.tmpl                |     0
 .../templates/{create => app}/projectName.iml.tmpl |     0
 .../src/main/res/mipmap-hdpi/ic_launcher.png       |   Bin 0 -> 544 bytes
 .../Flutter.tmpl/src/main/AndroidManifest.xml.tmpl |     0
 .../settings.gradle.copy.tmpl}                     |     0
 .../common}/.idea/modules.xml.tmpl                 |     0
 .../AppIcon.appiconset/Icon-App-1024x1024@1x.png   |   Bin 0 -> 11112 bytes
 .../AppIcon.appiconset/Icon-App-20x20@1x.png       |   Bin 0 -> 564 bytes
 .../AppIcon.appiconset/Icon-App-20x20@2x.png       |   Bin 0 -> 1283 bytes
 .../AppIcon.appiconset/Icon-App-20x20@3x.png       |   Bin 0 -> 1588 bytes
 .../AppIcon.appiconset/Icon-App-29x29@1x.png       |   Bin 0 -> 1025 bytes
 .../AppIcon.appiconset/Icon-App-29x29@2x.png       |   Bin 0 -> 1716 bytes
 .../AppIcon.appiconset/Icon-App-29x29@3x.png       |   Bin 0 -> 1920 bytes
 .../AppIcon.appiconset/Icon-App-40x40@1x.png       |   Bin 0 -> 1283 bytes
 .../AppIcon.appiconset/Icon-App-40x40@2x.png       |   Bin 0 -> 1895 bytes
 .../AppIcon.appiconset/Icon-App-40x40@3x.png       |   Bin 0 -> 2665 bytes
 .../AppIcon.appiconset/Icon-App-60x60@2x.png       |   Bin 0 -> 2665 bytes
 .../AppIcon.appiconset/Icon-App-60x60@3x.png       |   Bin 0 -> 3831 bytes
 .../AppIcon.appiconset/Icon-App-76x76@1x.png       |   Bin 0 -> 1888 bytes
 .../AppIcon.appiconset/Icon-App-76x76@2x.png       |   Bin 0 -> 3294 bytes
 .../AppIcon.appiconset/Icon-App-83.5x83.5@2x.png   |   Bin 0 -> 3612 bytes
 .../LaunchImage.imageset/LaunchImage.png           |   Bin 0 -> 68 bytes
 .../LaunchImage.imageset/LaunchImage@2x.png        |   Bin 0 -> 68 bytes
 .../LaunchImage.imageset/LaunchImage@3x.png        |   Bin 0 -> 68 bytes
 .../Flutter.tmpl/README.md}                        |     0
 2323 files changed, 240859 insertions(+), 100260 deletions(-)
 mode change 100644 => 100755

Upgrading engine...
Checking Dart SDK version...
Downloading Dart SDK from Flutter engine 3757390fa4b00d2d261bfdf5182d2e87c9113ff9...
Unzipping Dart SDK...
Building flutter tool...
Running pub upgrade...
Downloading package sky_engine...                                   0.5s
Downloading common tools...                                         0.4s
Downloading windows-x64 tools...                                    0.6s
Downloading android-arm-profile/windows-x64 tools...                0.2s
Downloading android-arm-release/windows-x64 tools...                0.3s
Downloading android-arm64-profile/windows-x64 tools...              0.3s
Downloading android-arm64-release/windows-x64 tools...              0.3s
Downloading android-arm-dynamic-profile/windows-x64 tools...         0.3s
Downloading android-arm-dynamic-release/windows-x64 tools...         0.3s
Downloading android-arm64-dynamic-profile/windows-x64 tools...         0.5s
Downloading android-arm64-dynamic-release/windows-x64 tools...         0.3s
Downloading android-x86 tools...                                    0.5s
Downloading android-x64 tools...                                    0.5s
Downloading android-arm tools...                                    0.3s
Downloading android-arm-profile tools...                            0.4s
Downloading android-arm-release tools...                            0.3s
Downloading android-arm64 tools...                                  0.3s
Downloading android-arm64-profile tools...                          0.3s
Downloading android-arm64-release tools...                          0.4s
Downloading android-arm-dynamic-profile tools...                    0.3s
Downloading android-arm-dynamic-release tools...                    0.5s
Downloading android-arm64-dynamic-profile tools...                  0.5s
Downloading android-arm64-dynamic-release tools...                  0.4s

Flutter 0.5.7 • channel dev • https://github.com/flutter/flutter.git
Framework • revision 66091f9696 (8 months ago) • 2019-02-14 19:19:53 -0800
Engine • revision 3757390fa4
Tools • Dart 2.0.0-dev.63.0.flutter-4c9689c1d2

Running flutter doctor...
Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel dev, v1.2.1, on Microsoft Windows [Version 10.0.16299.904], locale en-US)
[√] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
[√] Android Studio (version 3.3)
[√] VS Code (version 1.31.1)
[!] Connected device
    ! No devices available

! Doctor found issues in 1 category.
'napshot_pathflutter_tools_dirscript_path"' is not recognized as an internal or external command,
operable program or batch file.
Error: Unable to create dart snapshot for flutter tool.
```