Restore cache after install step so submodule build directories can be cached

[matthargett]

In http://github.com/ReactWindows/react-native-windows , we have ChakraCore as a submodule and we delegate to its build in our project.

Since we don't update the hash of the submodule often, we'd like to cache ChakraCore's Build/VcBuild/bin directory so we don't re-build it unnecessarily.

Currently, we can't do that because the cache restore happens before the install step where we do our 'git submodules update --init' command. The command fails when the ChakraCore submodule directory isn't empty, and --force doesn't push past the issue.

[IlyaFinkelshteyn]

Hi Matt,

Could you please try to use custom git clone scriopt (clone_script in YAML, or Settings > Clone script in UI). In this script you can do both git clone and git submodules commands and all will happen before cache is restored.

Please let us know if this helps.

Thank you,
Ilya.

[matthargett]

• That

  worked! For reference, here's the excerpt from my appveyor.yml:

cache:
- ReactWindows\packages -> ReactWindows\**\packages.config
- '%USERPROFILE%\.nuget\packages -> ReactWindows\**\project.json'
- ChakraCore\Build\VcBuild -> ChakraCore\lib\Common\*.h

clone_script:
- cmd: >-
    git clone -q --branch=%APPVEYOR_REPO_BRANCH% https://github.com/%APPVEYOR_REPO_NAME%.git %APPVEYOR_BUILD_FOLDER%

    cd %APPVEYOR_BUILD_FOLDER%

    git checkout -qf %APPVEYOR_REPO_COMMIT%

    git submodule update --init --recursive

before_build:
- ps: >-
    Get-ChildItem .\ChakraCore\Build\VcBuild * -recurse | ForEach-Object{$_.LastWriteTime = get-date}

It looks like the cached files don't get their timestamp updated on restore, so the submodule update would get files that appeared to be newer and still kick off the ChakraCore build. So I added the before_build line to set the timestamp on all files in the cache-restored directories, which short-circuited more of the submodule's build like I was hoping.